Download - Linn County West Feasibility Report 092209
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Introduction
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Linn County West Feasibility ReportSeptember 22, 2009
Introduction
Linn County West (LCW) is the adaptive re-use of a building constructed in 1978-79 as a
Montgomery Wards department store, one of four original anchor stores for Westdale Mall
shopping center. The LCW building contains just under 120,000 gross square feet of space
divided between two levels. Almost 75,000 square feet are located on the lower level and almost
45,000 square feet including the mechanical penthouse and the unheated Outdoor Sales Area
are on the upper level. Both levels are directly accessible from surface parking lots and both
levels have direct access to Westdale Mall.
Linn County leased the space to provide emergency housing for a number of its departments
displaced by the 2008 flood. Linn County would now like to consider the feasibility of converting
the former Montgomery Wards store into permanent County administrative offices.
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Linn County West Feasibility ReportSeptember 22, 2009
In an attempt to make the findings of this feasibility study comparable with other options that the
County is considering, the renovation of Linn County West has the following goals:
1. Provide permanent office space for the departments currently located at Linn County West
and identified by Linn County as intended to remain.
2. Provide permanent office space for as yet unidentified departments, agencies or tenants
with a similar use of space as those departments being relocated to other facilities from
Linn County West.
3. Bring Linn County West into conformance with current building and energy Codes.
4. Provide finishes consistent with proposed renovation of the Linn County Administrative
Office Building (AOB).
5. The offices located at Linn County West are to remain open and accessible to the public
throughout construction.
6. The renovated Linn County West will qualify for LEED Silver certification.
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Executive Summary
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Linn County West Feasibility ReportSeptember 22, 2009
Executive Summary
Area of Linn County West
Land: 8.9+/- Acres
Building: 119,544 s.f.
Renovation Goals
1. Provide permanent office space for the departments currently located at Linn County West
and identified by Linn County as intended to remain.
2. Provide permanent office space for as yet unidentified departments, agencies or tenants
with a similar use of space as those departments being relocated to other facilities from
Linn County West.
3. Bring Linn County West into conformance with current building and energy Codes.
4. Provide finishes consistent with proposed renovation of the Linn County Administrative
Office Building (AOB).
5. The offices located at Linn County West are to remain open and accessible to the public
throughout construction.
6. The renovated Linn County West will qualify for LEED Silver certification.
Renovation First Cost: $ 15,289,000
Anticipated Annual Energy Costs: $ 77,500
Annual Common Area maintenance (CAM) Fees $ 50,000
Life Cycle Cost Analysis: Calculated Total Present Worth $ 19,409,030
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Space Needs
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Linn County West Feasibility ReportSeptember 22, 2009
Space Needs
The current configuration of spaces in the Linn County West building includes a number of
agencies or departments already scheduled to be relocated to other facilities. The specific space
requirements for these agencies are not included as part of this study, but the square footage they
occupy is. These departments or agencies scheduled for relocation include:
Clerk of Courts Juvenile & Traffic
Court Family, Traffic & Juvenile
General Assistance
Juvenile Probation
Linn County Community Services (LCCS)
LCCS Financial
LCCS Conference Rooms
MHDD Case Management
MHDD / CPC
MHDD In-Home Services & Supervised Apartment Living
MHDD - Intake Services
MHDD Protective Payee
Veterans Affairs
Most of these agencies are located on the second floor of the LCW building and occupy all of that
level except the Loading Dock and Purchasing/Mail Room. Family, Traffic and Juvenile Court, the
Clerk of Courts for Juvenile & Traffic and the Juvenile Probation office occupy a large area on the
ground floor of the LCW building.
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Linn County West Feasibility ReportSeptember 22, 2009
The Board of Supervisors has considered other departments currently housed at the LCW
building for relocation to the Administration Office Building (AOB). These other departments
would remain at Linn County West if renovation of this facility into permanent county offices is
judged to be more feasible than other options. Table 1 lists the agencies that would remain at
LCW, the square footage they currently occupy, the space that has been assigned for them at the
AOB, and the space that has been budgeted to them in the LCW for this study. The larger square
footages occupied by each department in the current configuration is assumed to be the result of
inefficiencies in the layout driven by the need to locate the offices in the LCW quickly and with
minimum remodeling. The AOB space assignments result from a more careful consideration of
departmental needs and more accurately reflect the true space requirements for each
department. The program spaces used for this study are based on the space assignments
established for the AOB.
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Linn County West Feasibility ReportSeptember 22, 2009
Table 1: Space Needs for County Departments Identified To Remain At LCW
LCW Current
Space Usage
AOB Space
Assignment
Assumed
Space Needs
Departments to Remain at LCW Sq. Ft. Sq. Ft. Sq. Ft.
Assessor County 3,024 2,668 2,700
Auditor 7,104 4,480 4,500
Board of Supervisors / Finance 3,536 3,500
Human Resources / Risk6,984
1,680 1,700
Supervisors Meeting Room 1,152 1,928 2,000
Purchasing / Mail Room 1,728 1,232 1,200
Recorder 5,760 4,928 4,900
Treasurer / Motor Vehicle 10,080 6,048 6,000
Planning / Development 4,608 2,760 2,800
IT Dept. 4,032 3,192 3,200
Facilities Unknown 2,658 2,700
Shared Conference Rooms 690 6,104 6,100
Electrical/Communications 285 400
Mechanical Spaces3,664
899 1,500
Total 48,826 42,398 43,200
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The total area of program spaces identified in Table 1 is considerably less than the available
space in the building. For the purposes of calculating air conditioning requirements and energy
demands for this study, it will be assumed that the County would fill the available space in the
building with other departments having similar offices.
Conference rooms are necessary to conduct routine business in most offices. Because they are
typically not used continuously, conference rooms offer an opportunity to share a resource among
departments. Strategic location of the conference rooms allows individual departments to take
ownership of smaller conference rooms, controlling that rooms scheduling for their convenience,
while facilitating the use of that same room by other departments when needed. Larger
conference rooms should be considered community property and should be located so that they
are not likely to become the property of any one department. Instead they should be located for
convenient use by multiple departments or by the public.
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Existing Conditions
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Available Space
The Lynn County West building includes 74,820 gross square feet on the lower level. The upper
level includes 36,444 gross square feet plus 4,616 gross square feet in what had previously
been known as the Outdoor Sales Area.
The Outdoor Sales Area is protected by its roof, a wall it shares with the main building on the
north and another wall that separates it from some mechanical spaces on the east. The south
and west sides are open to the weather, enclosed only by columns supporting the roof with steel
gates between. Since the closing of the Wards store, painted plywood attached to the interior
side of the steel gates has sealed the space from public view and to reduce the need for
maintenance in the area. Although not originally intended as part of the buildings interior space,
it would not be difficult to renovate this area into interior space. However, for the purposes of
this study, when energy costs and life cycle costs are calculated, the Outdoor Sales Area will
not be counted as conditioned interior space.
The following table summarizes the available space at Linn County West:
Table 2: Available Space at Linn County West
Upper Level
Primary Space 36,444 g.s.f.
Former Outdoor Sales 4,616 g.s.f.
Mechanical Penthouses 2,991 g.s.f.
Mechanical Rooms 673 g.s.f
44,724 g.s.f.
Lower Level 74,820 g.s.f.
Total 119,544 g.s.f.
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Linn County West Feasibility ReportSeptember 22, 2009
The land associated with Linn County West covers an area of just under nine acres and
includes driveways and paved parking areas on the north, east and south sides of the building.
Surface parking is provided for 553 vehicles. The parking areas and driveways are paved with
asphalt originally installed in 1980. The condition of the asphalt is poor. Stormwater
management occurs off-site.
Existing Conditions: Site
Most of the site beyond the footprint of the Linn County West building is paved for walks, drives
and parking. Most of that pavement is in poor condition and has been allowed to deteriorate to
the point that it should be replaced. Vegetated areas are limited to a narrow strips between the
building and the perimeter sidewalk, to a steep side slope separating the south parking area
from the east parking area, to a small and narrow side slope separating the east parking area
from an entrance drive, and one small, triangular island marking the north side of an access
drive. There is no provision for detaining or treating stormwater on site.
Existing Conditions: Building Structure and Envelope
The Linn County West building is a free-standing, two-story, steel-framed structure independent
of the structure of Westdale Mall. Elements of the existing steel frame appear to be in good
condition as does the elevated floor slab. The joint separating the two structures is bridged by
cap flashing and sealants on the exterior, and by joint covers on the interior. If the mall building
were to be razed, wall materials would be exposed to view and to the weather that were not
intended to be exposed. The Linn County West building would remain essentially complete, but
new cladding would be needed in these areas to protect and conceal the newly exposed wall
materials.
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Linn County West Feasibility ReportSeptember 22, 2009
A building envelope is the assembly of materials that shelter the buildings interior spaces from
the outdoor environment: the roof, the walls with doors and windows, the foundation and the
floor slab at grade. The visual characteristics of the building envelope provide cues to a
buildings style and appeal. The performance characteristics of the building envelope play a
large role in determining a buildings energy efficiency and the comfort of its inhabitants.
The existing building envelope at Lynn County West is in need of extensive maintenance work.
Water infiltration to occupied spaces following recent rains indicates that the building envelope
may be failing at a number of points. The building is poorly insulated by todays standards. The
masonry exhibits extensive damage attributable to water infiltration and thermal movement.
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The original roof design was a built-up bituminous membrane laid over 2 1/4 of rigid insulation
on a structurally sloped roof deck. The existing roofing system is a fully-adhered TPO
membrane over insulation on most of the building area. Two areas of roofing flanking the
mechanical penthouse have a ballasted TPO membrane. No roofing cores were taken at the
time observations were made for this study to determine the type or thickness of insulation in
the current roofing assembly. A warranty placard on display at the roof access indicates that
the TPO roofing system was under warranty until August 7, 2002. The system is now seven
years beyond its warranty date. Observations on the roof of fresh sealant applied at membrane
flashing keeper bars, of newer membrane patches and of ballast raked back to expose
membrane seams suggest an on-going battle against leaks. The roof exhibits numerous repairs
and is old enough that total replacement as part of the renovation makes the most sense.
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The exterior masonry is a veneer of dark-colored, king-size, fired-clay brick units set in a 1/3
running bond. Typically, the masonry has an 8 steel stud frame back-up, but in specific areas,
such as at stair towers or at elevator shafts, the masonry has a concrete block back-up. There is
3 batt insulation with a vapor barrier facing the buildings interior between the studs where
the back-up is steel stud framing. Only thick rigid insulation is indicated for locations having
block back-up.
Typical for masonry veneer wall construction in the late 1970s, the wall is treated as a barrier
with little or no provision made to manage water that may infiltrate the wall system. There is no
space between the brick veneer and its back-up to channel water away from the buildings
interior. There is no damp-proofing or building wrap indicated between the brick and the back-up
sheathing. No through-wall flashings are indicated in the plans for the foundation-masonry
interface or for other key locations, and no evidence of through-wall flashings was observed on
site. Relief joints in the masonry require new sealants. The existing sealants at relief joints have
cracked and pulled away from the masonry, providing little or no protection against water
infiltration.
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Linn County West Feasibility ReportSeptember 22, 2009
There are no windows penetrating the masonry envelope. The only windows to the exterior in
the Linn County West building are side lights at the entrance vestibules and some skylights over
the escalators. The absence of natural light in the buildings interior may have been suitable for
a department store, but it is not acceptable for office space.
Parapets are those portions of the wall rising above a buildings roof line. The Linn County West
building features fairly tall parapets made to look like a seamless continuation of the wall below.
The framing for the parapets is typically a balloon-framed extension of the lower walls back-up
framing. The roof side of most parapets is clad with painted, corrugated steel panels over a
double layer of gypsum board sheathing. The paint on the steel panels is heavily oxidized and
the panels exhibit rust in many places. The wall that is common with mall is faced with fired clay
brick set in a 1/3 running bond backed with concrete masonry units. Metal cap flashings at
parapets also exhibit some rusting.
The Linn County West building also features five porches at the public entrances. The porches
feature masonry columns supporting massive masonry volumes designed to break down the
buildings scale and provide visual interest. The masonry volumes provide no usable space
within the building. The porches also feature banks of skylights over key entrances. The
masonry at the porches is in poor condition. There is evidence of water leaking into the wall
system from the skylights and of thermal stress on the brick units.
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Linn County West Feasibility ReportSeptember 22, 2009
The original construction drawings show that the concrete foundations were to be protected
from water infiltration by the application of a 20 mil neoprene membrane extending from grade
to the footing, and with a flashing of the same neoprene material across the top of the footing
adding protection to the joint between the footing and the foundation wall. Four-inch diameter
footing drains to intercept ground water were to be installed at the base of the south foundation
wall and along the south end of the east foundation wall where the earth is graded up to the
buildings upper floor level. No clean-outs were observed for this footing drain and no outlet for
this drain was observed. No determination of silting within the drain could be made. Whether or
not the footing drain is functioning at all was not determined. County employees have installed a
new sump and pump along the buildings east wall outside of the freight elevator shaft. The new
sump pump is set to discharge water to the adjacent planting bed.
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The original construction drawings indicate that 1 thick rigid insulation was to be applied to the
top four feet on the exterior side of foundations walls that were not exposed. Where the upper
parts of foundation walls were exposed, such as at the loading docks, the insulation was to be
applied to the first four feet below grade. The existence or condition of this insulation has not
been confirmed.
The original construction documents show the floor on the ground level of the building
constructed as a 4 concrete slab over a 6 mil membrane on a sand bed at least 4 thick. A
water stop was to have been cast into the joint between the floor slab and the foundation wall.
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Existing Conditions: Electrical Power Distribution and Lighting
Linn County West inherited a 277/480 volt, 3,000 amp electrical service when it took possession
of the former Montgomery Wards store. The main switchboard is fed from a pad-mounted
transformer owned by Alliant Energy. The main switchboard feeds several 277/480 volt
distribution panels throughout the facility as well as a motor control center located in the
mechanical penthouse. At each 277/480 volt distribution panel location there is a transformer
and 120/208 volt panelboard. The original design drawing indicates that the large feeders used
aluminum conductors.
Generally, the electrical distribution system is functional; however, it is nearing the end of its
service life. Since the facility was designed as a department store, the major electrical loads
were cooling, heating and lighting with little 120/208 volt distribution. At least two of the
underground feeder conduits were conveying ground water into the distribution panels.
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Emergency power is provided by a 45 kW gasoline engine driven generator and an automatic
transfer switch feeding an emergency panel. The engine-generator is original to the building. It
was not functional at the time of inspection, but was in the process of being repaired. The
engine generator is at the end of its service life and does not meet Linn Countys requirements
to have emergency power for the entire facility.
Lighting systems in the building date to the original construction. Open areas are lit with 6-lamp
fluorescent fixtures with egg-crate grills. Storage areas are lit with continuous rows of open
lamp fluorescent T12 strip fixtures. Lighting control is through lighting contactors distributed
throughout the facility.
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The existing lighting systems exceed current energy code power density limits. The light fixture
type and light distribution is not appropriate for an office environment.
Existing telecommunicating infrastructure consists of a central computer room and intermediate
distribution points located throughout the facility. All current telecommunication facilities were
installed by the County. All telecommunications facilities will require replacement or relocation to
dedicated equipment spaces and cable pathways.
The existing fire alarm system is an addressable Notifier system with audible and visual
annunciation throughout the building and with smoke detection in select areas. The system
does not meet the Countys requirement to combine the fire alarm with a mass communication
system and no components are salvageable.
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Existing Conditions: Mechanical Systems
Cooling
The building is cooled by three water cooled reciprocating chillers and a cooling tower located
on the roof outside the mechanical penthouse. The mechanical penthouse also contains two
custom built air handling units. Each unit contains a large array of pleated filters, direct
expansion cooling coils and a belt driven fan with inlet vanes for air volume control. HR Green
was unable to determine whether the inlet guide vanes still operated or what controls the
position of the vanes. Conditioned air is delivered to spaces via ductwork containing variable air
volume boxes that modulate in response to space temperatures. Air is returned to the unit
through a return air plenum above the ceiling on both floors. The mechanical penthouse
contains two large outside air louvers and two large relief air louvers each with roll-up doors on
the exterior side. Outside air and return air are mixed in the space outside the air handling unit
rooms. Currently, both relief air louvers are blocked causing relief air to exit by exfiltration
through mall entrances. One outside air louver has been blocked and the other has been
reduced in size resulting in an unknown amount of outside air entering the building.
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The cooling system dates from original construction with very few modifications since that time.
The system was reported to be functional but all the equipment has exceeded its useful life.
The cooling tower shows signs of organic deposits on the interior of the unit which reduces the
efficiency of the unit. The chillers are less efficient than currently available cooling systems and
also contain the refrigerant R-22 which is being phased out of production in 2010. The existing
ductwork is sized and arranged to accommodate an open floor plan department store. The
ductwork is not sized correctly nor will the ductwork layout be sufficient when the space is
converted to an office type environment. In addition, due to its age, the ductwork is assumed to
have air leaks which result in higher energy costs. The entire cooling system including
ductwork and the air handling units will require replacement.
The computer/communications room is cooled year-round by a split system air conditioning unit
installed as part of the temporary renovation required for the county to occupy the building. The
space is served by a single unit and no backup system is present if the primary system fails.
Heating
The building is heated by a separate ductwork system. Electric resistance furnaces are located
above the ceiling and scattered throughout the building. The furnaces use air from the return
plenum above the ceiling and supply warm air through diffusers identical in appearance to the
cooling system diffusers. Smaller spaces created by the temporary remodel are likely to have
only one supply of air (hot or cold). Heat in entrances and auxiliary spaces is provided by
electric unit heaters and electric radiant heaters. Electric baseboards are used to handle the
skin loads in rooms with exterior walls. The two air handling units are reported to still operate
during the winter months to provide ventilation air to the building. The ventilation air is not
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conditioned during the winter and a high return air to outside air ratio must be relied upon to
keep supply air temperatures high enough to avoid occupant discomfort.
The use of electric resistance heating throughout the building leads to high electrical
consumption and demand charges during the winter months. In addition, the entire heating
system dates from original construction making the equipment approximately 31 years old. The
equipment has exceeded its useful life and is an inefficient way to heat the building. The entire
heating system will require replacement.
Controls
The building is currently controlled by a pneumatic control system dating from the original
construction. The control system is reported to be working but the level of actual control over
the system is unknown. Due to the age of the system, it is very likely that the control has
diminished since original installation and that portions of the system may not function. In
addition, current Linn County building standards utilize direct digital control systems. The
control system will need to be completely removed and replaced.
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Fire Protection
The existing fire protection system was installed to meet the requirements of an open floor plan
department store. Conversion of the space to an office layout will change the sprinkler
requirements. In order to adequately protect the new layout, the existing sprinkler will need to
be completely demolished and a new system designed and installed.
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Plumbing
The building contains plumbing from original construction along with new plumbing that was
added to meet the needs of the temporary reconstruction. Locations of restrooms and quantity
of fixtures will be modified if the space is remodeled resulting in the need to remove all existing
plumbing. The existing fixtures do not meet the water efficiency requirements of the Energy
Policy Act (Epact) of 1992 or the LEED rating system and they will need to be replaced with
more water efficient fixtures.
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Project Constraints
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Applicable Codes
As a County-owned facility, Linn County West is subject to applicable Linn County Codes:
International Building Code (IBC), 2006 Edition as amended by the Linn County Board
of Supervisors;
International Fire Code (IFC), 2006 Edition as amended by the Linn County Board of
Supervisors;
Uniform Plumbing Code (UPC), 2003 Edition as amended by the Linn County Board of
Supervisors;
ICC Electrical Code, 2006 Edition as amended by the Linn County Board of
Supervisors;
Linn County Mechanical Regulations:
o International Mechanical Code (IMC), 2006 Edition as amended by the Linn
County Board of Supervisors;
o International Fuel Gas Code (IFGC), 2006 Edition as amended by the Linn
County Board of Supervisors.
The Cedar Rapids Zoning Ordinance applies to parking requirements. (Section 32.05.020
Parking Standards, B. Off-Street Parking Requirements, 2. Amounts of Off-Street parking
Required See Table 32.05-4:Minimum Off-Street Parking Requirements for Office; business,
professional, or governmental not listed separately: 4 per 1,000 s.f. Gross Floor Area.) With a
gross floor area of 119,544 square feet, Linn County West is required to provide 479 off-street
parking spaces.
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Easements and Agreements
The real estate associated with Linn County West is encumbered with a series of easements
and agreements that integrate the use of the building and land associated with Westdale Mall
with the building and parking areas belonging to Linn County West. These provisions grant each
party easements into, over and across each others land and define how the maintenance and
operation of common areas will be managed and paid for. Succession and assignment clauses
cause the easements and agreements to run with the land and to survive changes in ownership
until July 14, 2037.
Some of the key easements are:
For the passage and parking of vehicles and accommodation of pedestrians;
The right to eject persons not authorized to use the common area;
For the installation, operation, maintenance, repair or relocation of underground utilites;
For the purposes of development and construction.
Key agreements address common area development and maintenance and include:
Proportional responsibility for costs associated with construction of improvements to the
common areas;
Allocable Share of Common Area Maintenance Costs (CAM)
Restrict designated employee parking to spaces at least 250 feet from the enclosed
mall;
Process for withdrawing a tract from the maintenance and operation provisions of the
agreement for the common areas;
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Required parking ratio (5.3 automobile parking spaces for each 1,000 gross square feet
of floor area = (119,544 g.s.f. / 1,000 g.s.f) x 5.3 = 634 automobile parking spaces.);
Membership in the Merchants Association;
Maximum development of floor area for Linn County West limited to 126,000 square
feet;
Signage characteristics;
Some costs to Linn County West associated with the Common Area Maintenance (CAM)
provisions are known. For the purposes of this study, the CAM assessments will be assigned
the value of $50,000 annually. Other costs, such as the dues for membership in the Merchants
Association are unknown and not factored into the operating costs addressed in this study.
If Linn County were to pursue making the former Wards store into permanent County offices, it
may want to open negotiations with the Mall operator over issues such as membership in the
Merchants Association and its share of CAM fees. The CAM fees are structured on the
assumption that every property or tenant associated with the mall benefits equally per square
foot from the amenities of the enclosed mall. This may have been true when all of the occupants
were retail businesses that depended for their revenues on the traffic these amenities
generated. The County enjoys no such benefit, and in fact may help to generate traffic to the
benefit of its neighbors at the mall.
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LEED
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LEED Silver Certification
Linn County has set a goal for the renovation of Linn County West to be certified with a LEED
Silver rating. The LEED(Leadership in Energy and Environmental Design) Green Building
Rating System is a voluntary, third-party certification process that evaluates projects using a
consensus-based rating system for the design, construction and operation of high-performance
green buildings. LEED 2009 for New Construction and Major Renovations, recently published
by the U.S. Green Building Council, provides the criteria used by this study.
LEED has four levels of certification:
Certified, Silver, Gold and Platinum.
A project must earn 50-59 of the
possible 100 points available in the
rating system to achieve LEED Silver certification. Key areas evaluated in the certification
process include Sustainable Site Development, Energy Efficiency, Indoor Environmental
Quality, Water Efficiency and Materials and Resources.
The Linn County West renovation project offers many opportunities to make improvements in
each of these areas. A preliminary tabulation of the potential LEED points this project could
earn indicates that the Linn County West renovation can achieve LEED Silver certification with
55 LEED points. See Appendix A.
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Sustainable Site Development
(21 LEED Points Anticipated)
The site scores very well in the categories of good community connectivity and access to public
transportation with no effort. Linn County West can earn five points for its location alone: It is
located on a previously developed site. It is within mile of a residential neighborhood
averaging ten housing units per acre. It is within mile of at least ten basic services and has
pedestrian access between Linn County West and those basic services. Another six points is
earned because two Cedar Rapids Transit bus routes, Route #10 and Route #12, run to
Westdale Mall and have stops within mile walking distance from the front entrance of Linn
County West.
The project can earn an additional LEED point by providing bicycle storage for at least 5% of all
of the building users in conjunction with providing shower and changing facilities for % of the
buildings full-time equivalent employees. Another three LEED points can be earned by
reserving 5% of the parking spaces for low-emitting and fuel efficient vehicles and locating those
reserved spaces closest to building entrances. (Spaces reserved for handicapped persons will
always have precedence in being located close to building entrances over other kinds of
reserved parking.)
Choices made regarding the design of the proposed roof replacement and re-pavement of the
parking areas can result in a reduction of the heat island effect and possibly earn another two
LEED points. Choosing parking lot lighting fixtures that direct light downward and do not bleed
light off of the property will earn another point for Light Pollution Reduction.
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Additional work could be done to reduce the rate of stormwater run-off from Linn County West,
and to improve the quality of stormwater discharged from the site. However, these
improvements would have a large impact on the project cost and only earn a maximum of two
LEED points, so they have not been included among the strategies being pursued in this study.
Water Efficiency
(6 LEED Points Anticipated)
Water use reduction by 20% is a prerequisite of the LEED certification. This study anticipates
reducing water use at Linn County West by 30% to earn two LEED points. All of the existing
plumbing fixtures, which are thirty years old, are proposed to be replaced with new, water-
conserving fixtures in the renovation.
The local plumbing Code does not permit the use of gray water for flushing toilets. Further
reductions in water use can be achieved, however, by selecting plant materials for landscape
areas that require little or no irrigation and by using only collected rainwater for the irrigation that
does occur. The project could earn an additional four LEED points for eliminating the need for
using potable water for landscape support.
Energy & Atmosphere
(13 LEED Points Anticipated)
LEED has three prerequisites that must be met before any
additional points are earned in the Energy and Atmosphere
category: Fundamental Commissioning must be performed to verify
that the projects energy-related systems are installed and calibrated
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to perform as intended. The renovated buildings energy performance must be 5% better than
the renovated buildings calculated baseline performance rating. The renovated buildings HVAC
system must use no CFC-based refrigerants.
Most of the LEED points to be gained under the category of Energy Efficiency will be found in
the sub-category of Optimize Energy Performance. Optimizing energy performance involves
the pursuit of strategies that improve a buildings energy performance beyond the standard of
the prerequisite. Strategies for optimizing a buildings energy performance include
improvements to the building envelopes thermal performance, use of high-efficiency HVAC
systems, the use of high efficiency lighting fixtures, and the use of occupancy sensor controls
for lighting and ventilation. This study anticipates earning seven LEED points for optimizing Linn
County Wests energy performance.
Other strategies proposed for earning LEED credits under the category of Energy & Atmosphere
for Linn County West include Enhanced Commissioning, Enhanced Refrigeration Management
and Measurement & Verification.
Enhanced Commissioning involves an independent commissioning authority who reports
directly to the Owner early in the design process to lead, review and oversee the completion of
all commissioning process activities. The Commissioning Authority participates through the
construction period to review contractor submittals and to perform basic commissioning
services. Ten months after substantial completion the Commissioning Authority reviews
operation of the building and provides recommendations for fine-tuning or recalibration of
systems. Enhanced Refrigeration Management requires the selection of central HVAC
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equipment that minimizes the use of ozone-depleting refrigerants and the implementation of an
equipment maintenance program to prevent refrigerant leakage. Measurement & Verification
requires the development and implementation of a plan to meter equipment and track energy
use against the predicted performance of the design. This study anticipates earning six more
LEED points for pursuing these strategies.
Materials and Resources
(2 LEED Points Anticipated)
The category of Materials and Resources awards LEED points for the recycling and re-use of
used materials, the incorporation of recycled materials into new work, the re-use of existing
buildings, minimizing the distance materials need to be transported and for the selection of
renewable products. It is the realization of the concept to reduce, reuse, recycle at the heart of
the green movement. The Linn County West Renovation project will pursue points under the
subcategories of Construction Waste management and Regional Materials.
Construction Waste management involves recycling or salvaging nonhazardous construction
and demolition debris. A construction waste management plan would be implemented to identify
materials that are to be diverted from the waste stream. For the Linn County West project
materials that could be diverted from the waste stream include: light gauge steel framing
members, hollow metal doors and frames, gypsum board, glass, aluminum storefront framing,
copper piping and cables, steel ceiling suspension grid, fired-clay brick, Portland concrete and
asphaltic concrete. It is assumed that these materials will easily constitute over 55% of the total
waste by weight generated for this project. Implementation of construction waste management
plan would earn the project one LEED point.
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Regional Materials awards points for the incorporation of materials that are extracted and
manufactured within 500 miles of the project to minimize the impact of transporting materials. It
is assumed that at least 10% of the materials incorporated into the Linn County West
renovation, based on cost, will be from sources within that 500 mile radius earning one more
LEED point.
This study is not assuming that the Linn County West project will earn the any of the three
LEED points available for the re-use of an existing building. At least 55% of the original
buildings structure and envelope must be re-used to qualify for the first point. The Linn County
West renovation project may not meet this threshold because this study assumes that all of the
existing masonry veneer will be replaced to enhance the buildings thermal performance and
water infiltration management.
Indoor Environmental Quality
(8 LEED Points Anticipated)
The Indoor Environmental Quality credits support project choices that enhance the health and
well-being of building occupants through the reduction of indoor air pollutants, good ventilation,
reduction of indoor contaminants and provision of the means to isolate and filter those
contaminants that are present, the introduction of natural daylight into occupied spaces and
views to the outside.
This study focuses on those sub-categories addressing indoor air quality, control of lighting
systems by occupants and thermal comfort for strategies to earn LEED points. The HVAC
system for the Linn County West renovation is assumed to include a building automation system
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that monitors air flow and carbon dioxide levels, and issues a warning when measurements vary
by more than 10%. Monitoring outdoor air delivery in this way earns one LEED point.
Implementing an indoor air quality plan during construction is important because the facility will
be occupied throughout construction, and it will earn the project one more LEED point.
Specifying low-emitting adhesives and sealants, paints and coatings, and carpet systems
reduces the contamination of indoor air with volatile organic compounds (VOC) and earns
another three LEED points for the project.
Providing control of lighting to individual occupants or groups of occupants allows them to tailor
their light usage to their particular needs and earls one more LEED point for the project.
Providing occupant control for thermal comfort may be achieved through multiple strategies
including the use of individual thermostat controls, operable windows, manual diffuser dampers
and control of individual radiant panels. Enabling a minimum of 50% of the buildings occupants
to make adjustments to meet their individual needs and preferences will earn Linn County West
one LEED point.
This study also assumes that the Linn County
West renovation will be designed with an HVAC
system and building envelope meeting the
requirements of ASHRAE Standard 55-2004,
Thermal Comfort Conditions for Human
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Occupancy, earning one LEED point. The HVAC system would include a permanent monitoring
system to measure and track the buildings performance against design comfort criteria to
provide verification. Verification would be also be provided by a thermal comfort survey
proposed to occur six to eighteen months after occupancy to assess overall occupant
satisfaction with the thermal performance of the building or to identify thermal comfort-related
problems. These verification efforts will earn Linn County West one additional LEED point.
This study assumes that daylighting will be greatly enhanced at Linn County West by the
introduction of many windows and some skylights to a building that has virtually none now.
However, the geometry of the building makes it very difficult to meet the threshold to earn
additional LEED points for daylighting and views. This study does not assume any LEED points
will be earned under these subcategories.
Innovation in Design
(1 LEED Point Anticipated)
The Innovation in Design category provides one LEED point that should be a given on any project
seeking LEED certification: one LEED point for having a LEED accredited professional on the
design team. There are additional points that can be earned under this category for innovative
design. This study assumes that the point for including a LEED accredited professional is earned,
but does not assume any innovative design credits are earned.
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Regional Priority
(4 LEED Points Anticipated)
Regional Priority credits can are bonus points awarded in addition to the base 100 points available.
Up to four Regional Priority credits can be earned by obtaining the LEED credits for categories that
have been identified by the USGBC regional council as having special environmental importance
for that region. The following categories have been designated as regional priorities in the area of
Linn County West:
Sustainable Sites Credit 2: Development Density and Community Connectivity
Sustainable Sites Credit 4.1: Alternate Transportation Public Transportation Access
Sustainable Sites Credit 4.2: Alternate Transportation Bicycle Storage and Changing Rooms
Sustainable Sites Credit 6.1: Stormwater Design Quantity Control
Water Efficiency Credit 2: Innovative Wastewater Technologies
Materials & Resources Credit 2: Construction Waste Management
This study has already indicated anticipation that Linn County West will earn the available points for
four of the identified regional priorities: Development Density and Community Connectivity, for
Alternate Transportation Public Transportation Access, for Alternate Transportation Bicycle
Storage and Changing Rooms and for Construction Waste Management. Linn County West should,
therefore, qualify for the associated LEED points for Regional Priority.
It has been determined that a LEED Silver Rating is very achievable for the Linn County West
project. If the County chose to pursue all of the credits identified in this study as having a
moderate impact on the design for Linn County West, a total of 79 points could be earned for a
possible LEED Gold rating.
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Renovation Scope
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Renovation Scope
The scope of construction work required to achieve the goals of this renovation is assumed as
follows:
Site Work
This study assumes that all of the parking area and drives paved with asphalt will be repaved as
part of the Linn County West renovation. Two different strategies for replacing the pavement
were given consideration. The first strategy is the most basic: simply repave those areas
currently paved with asphalt with new asphalt. The second strategy considered the potential for
improving the sites stormwater retention by replacing 20% of the traditional asphalt paving with
a permeable pavement system. The construction cost for pursuing the second strategy was
42% greater than repaving with traditional asphalt. The goal of earning LEED Silver certification
for this project can be accomplished without incurring the cost of installing the permeable
pavement. For this study it is assumed that permeable pavement is not used.
Some additional green space will be obtained by the elimination of part of the truck well outside
of the loading docks on the south side of the buildings upper floor. The truck loading dock built
to support shipments to the Montgomery Wards department store is greatly oversized for the
operation of a county office building. Of the six existing loading bays, one is dedicated for refuse
collection and five are set up for loading and unloading semi trucks. At least three of the bays
will be converted to other uses and about 1,700 square feet of pavement front of them will be
demolished to create the new garden area.
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Building Demolition
Demolition of the existing finishes, partitions, fixtures and equipment will be extensive. This
study assumes that the roofing will be torn-off down to the metal roof deck. The exterior wythe
of masonry will be removed, but the steel back-up framing will be retained. The existing
entrance porches and their structure would also be removed. All interior partition framing and
gypsum board, finishes, plumbing, lights and equipment would be removed. The escalators
would be removed. The existing passenger elevator would also be removed. The existing fire
sprinkler system would be removed. And finally, the existing HVAC system and all of its
ductwork would be removed.
Building Construction
The building envelope will require a great deal of work. A new built-up roofing system will be
installed with insulation to raise the roofs R-value to 30. A green roofing system was
considered, but discarded for this study. The existing roof structure would need to be enhanced
to support the loads for a traditional green roof, and the LEED points available for this work
were not needed to achieve the goal of LEED Silver certification.
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Insulation for the exterior walls will also be enhanced raising their R-value to 24. The exterior
walls would be reconstructed to manage water infiltration. Masonry walls would be constructed
as rain-screen cavity walls with a 1 to 2 air space immediately behind the brick to intercept
water that penetrates the system and then channel it to flashings that redirect the water back to
the outside of the wall. A continuous 2 layer of rigid insulation board and a weather barrier are
located over the sheathing on the inboard side of the cavity to minimize thermal bridging at the
studs. Fiberglass batt insulation would be installed in the spaces between the existing 8 deep
steel studs. The wall would be finished with a continuous vapor barrier covered with 5/8
gypsum board on the interior side.
The added insulation and air space required for the masonry rain-screen cavity walls requires
an additional 4 wall thickness. Because we are re-using the steel stud back-up framing in
place, that entire additional width is toward the outside of the wall. Where masonry rain-screen
walls are to be constructed for this project, therefore, foundations will need to be made 4
thicker as well. Excavations to modify the foundations provide an opportunity to refresh
foundation damp proofing.
Not all of the existing masonry would be replaced with new masonry rain-screen cavity walls.
Introducing day lighting and views to the renovated building is part of the strategy for achieving
LEED Silver certification. Up to 40% of a wall can be opened as windows and still meet the
requirements of the Energy Code. Curtain wall rain-screen will be used in lieu of masonry in
some areas. Curtain wall provides the opportunity to introduce light and views, to manage water
infiltration and to enhance thermal performance without the need to make the foundation any
thicker.
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The number of entrances would be reduced. The existing building has four large entrances on
the lower level, two facing north and two facing east, plus one large entrance to the upper level
from the south. This study assumes that there will be only two entrances on the lower level, one
from the north and one from the east, and one to the second level from the south. Each exterior
entrance will feature two pairs of glass doors in a glass and thermally broken aluminum
storefront fame with a second set of two pairs of glass doors in a glass and storefront frame to
create a vestibule.
The number of sanitary plumbing fixtures will be increased and public restrooms will be
relocated for more convenient access. Most of the restroom fixtures are currently located on the
lower level near the center of the south wall. Three single-user restrooms are currently located
on the upper level near the west end of the south wall. With all of the restrooms combined, the
existing fixture count does not satisfy the requirements of the Uniform Plumbing Code for Linn
County Wests occupant load. For the purposes of this study it is assumed that the renovation
will provide one public restroom for each sex centrally located on each level, one public family
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restroom on each level located near the public restrooms, a staff restroom with a single shower
for each sex to be located near an employee lunch room and a private, unisex restroom located
near the Supervisors Board Room. A janitors closet with mop sink would be located on each
floor. Four pairs of drinking fountains would be located along corridors. Relocating plumbing
fixtures will entail cutting openings in the floor slab for installation of the new drains.
The escalators are to be removed because there is not enough
expected traffic to justify their continuous energy consumption
and because they represent a safety risk. During a visit to Linn
County West in preparation of this report, a senior citizen was
observed trying to descend on the escalator. He was unsteady
and having difficulty coordinating his step with the movement
of the escalator. In his first attempt he nearly pitched forward
down the steps. Before he tried again, one of the observers
suggested that he may prefer using the passenger elevator.
He was grateful to find out that there was a passenger
elevator. He had looked for one, but couldnt find it. For the renovation, we are proposing that
the escalators be replaced with a new, centrally located elevator, and that the two levels of Linn
County West should be connected with a new, centrally located open stairway.
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Power Distribution and Grounding
The electrical service will consist of a new 277/480,
electrical service with new distribution to mechanical
equipment, lighting panels and 120/208 volt branch
panels. Branch panels are to have 200% rated neutrals
for non-linear loads. All dry-type transformers are to be
NEMA T-3 energy efficient, and K-rated. Feeds will be
designed for a 2% max voltage drop. Surge protective devices (SPDs) will be provided
on the main switchboard and all 120/208 volt branch panels. A dedicated transformer
and branch panel will be provided for the main telecommunication room in accordance
with EIA/TIA 568.
A new grounding electrode system will be established and telecommunications
grounding system will be installed in accordance with EIA/TIA 607.
All conduits will be provided with an equipment ground conductor.
Emergency Power
The emergency power system will be capable of supplying power to the entire facility. A
diesel driven engine-generator will be housed in a walk in weatherproof enclosure with a
24 hour base mounted fuel tank. A closed-transition transfer switch will allow power to
EIA/TIA 607 TelecommunicationsGrounding Bars
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LED Task Lighting
be switched from source to source without interruption of power, allowing the facility to
be on an interruptible electrical rate, or control their electrical demand.
Lighting
A new fluorescent lighting system will be
designed to work with a new task lighting
system and provide an overall lighting
system with a power density of 0.75 watts
per square foot exceeding ASHRAE 90.1
and applicable Energy Codes. The
lighting system will utilize high-performance T8 lamp and ballast combination and LED
task lighting.
High Performance T8 Lighting
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A lighting control system incorporating daylighting control, occupancy sensors and
schedules will control the lighting system. Architectural lighting will be installed at select
public areas.
Exterior lighting will be designed to exceed energy code requirements. All exterior lights
will be full cut-off.
Telecommunications Infrastructure
The telecommunications infrastructure will be in accordance with EIA/TIA 568 and 569.
Category 6 cables will be routed through a cable tray system to a central
telecommunications room. Intermediate communication rooms will be provided as
required to meet EIA/TIA 568. Telecommunications shall be complete from the outlet to
the patch panel.
Access Control System and Closed Circuit Television
An Access Control System (ACS) using the Countys approved vendor will be installed.
The ACS will utilize proximity card readers to control exterior doors and select interior
doors. A total of 16 controlled doors are anticipated. An IP based closed circuit
television system will be interfaced with the access control system to record activity at
select controlled doors. Additional cameras will monitor public areas and public
transaction counters. A total of 16 cameras are anticipated.
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Fire Alarm withVoice Notification
Fire Alarm / Mass Notification System
A new addressable fire alarm system with voice annunciation
will be installed. Smoke detection will be limited to select
areas. The sprinkler system will be monitored and duct smoke
detectors will be installed where required. The mass
notification system will be capable of distributing an audible
message throughout the facility.
HVAC System
The new heating, ventilation and air conditioning (HVAC) system will consist of variable air
volume built up air handling units. The units will contain full energy recovery wheels that will
transfer thermal energy from the exhaust air stream to the outside air stream. The full energy
recovery wheels will decrease the energy costs associated with bringing outside air into the
building and will help the building obtain LEED silver certification. In addition, the units will have
full economizer capability in order to use cool, dry outside air for cooling when outside air
temperatures are suitable. This feature also helps to reduce the energy usage of the building
and contributes toward LEED silver certification. The fans on the air handling units will have
variable frequency drives that will vary the fan speed in response to building heating and cooling
demands. Variable air volume boxes with and without hot water re-heat coils will be located
throughout the building to provide individual temperature control for spaces.
The units will be equipped with outside air dampers to provide the amount of outside air
required by ASHRAE standard 62.1 in order to maintain acceptable indoor air quality for the
building. The units will use an energy saving feature called demand controlled ventilation to
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Centrifugal Chiller
determine the required amount of outside air during different levels of occupancy. The outside
damper will modulate to allow more or less outside air depending on the concentration of carbon
dioxide in the return air stream. This feature reduces energy consumption by delivering only the
needed outside air to the building.
Cooling for the building will be provided by two water-cooled
frictionless bearing centrifugal chillers, with each chiller
sized for 65 percent of the load. The chillers will provide
chilled water to each of the air handling units. The
condenser water will be cooled by a fiberglass cooling tower
located on the roof of the building. The frictionless chillers
exceed current energy code requirements for full-load and
part-load energy efficiency and will reduce the electrical usage of the building. The chillers also
use the environmentally friendly refrigerant R-134a which does not deplete the ozone and is not
currently subject to a phase-out schedule.
The building will be heated with gas-fired condensing hot water boilers. The boilers will provide
hot water to pre-heat coils located in the air handling units and re-heat coils located in variable
air volume boxes to allow for individual temperature control. Condensing boilers have
combustion efficiencies near 98 percent and will reduce the cost to heat the building.
Condensing boilers far exceed the energy code required efficiency for boilers and will contribute
to the building earning LEED silver certification.
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The computer/communication rooms will be cooled by a high efficiency dedicated computer
room air conditioning unit designed to operate year round. Each room will also have a variable
air volume box to provide backup cooling in the event that the computer room air conditioner
fails.
A ground source geothermal heat pump system was also evaluated for the Linn County West
Building. The current parking lot is in disrepair and will need to be replaced creating the
opportunity to install the borefield underneath the parking lot. A ground source geothermal
system has the potential to provide energy savings in addition to those provided by the system
described above. For purposes of this study, the built up air handling unit system with water
cooled chillers was used in order to maintain consistency with the proposed design for the
Administrative Office Building. The Weidt Group has been hired by MidAmerican Energy and
Alliant Energy to review the feasibility of installing a ground source geothermal system at the
Administrative Office Building and to investigate what potential rebates would be available from
the utilities.
Controls
The HVAC controls system will be a complete direct digital control system. The system will
control all of the HVAC equipment and to provide a central point of control for the building. The
control system will also reduce energy consumption by allowing for scheduling of occupied and
occupied periods. During unoccupied periods, temperatures will be reset to warmer
temperatures in the summer and cooling temperatures in the winter.
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Dual Flush Flushometer
Plumbing System
The new plumbing system will incorporate dual-flush toilets, low-flow
urinals, low-flow faucets, and low-flow showerheads to reduce the
building water consumption. The plumbing system will be designed to
meet the requirements of the Uniform Plumbing Code (2003). The
building will also feature a rainwater collection system that will collect
rainwater from the roof of the building and store for landscape irrigation.
The reduction of water usage by these strategies will help achieve the
LEED silver rating for the building.
Hot water for lavatories will be provided by instantaneous tankless water heaters located
underneath the lavatories. Tankless water heaters reduce the energy usage for hot water and
will help the facility to achieve the LEED silver certification. The restroom containing the shower
facilities will require an electric tank-type hot water heat to provide sufficient hot water to the
showers. Using this combination of point-of-use hot water heaters eliminates the cost of
installing hot water piping throughout the facility and eliminates the energy consumption of a hot
water circulation system.
Fire Protection
A new sprinkler system will be installed to meet the light-hazard occupancy classification of the
office areas and will be appropriately design to protect storage areas. The new system will be
designed in accordance with the International Fire Code 2006
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Sequence of the Work
Because the building will be occupied and open to the public throughout the renovation, the
demolition and subsequent construction will need to occur in a piecemeal fashion. It is assumed
that all of the departments scheduled to be relocated to alternate facilities have completed that
move before demolition begins, which leaves the upper level vacant except for Purchasing and
the Mail Room. The area on the lower floor currently occupied by the Courts, the Clerk of Court
and Juvenile Probation will also be vacated. Having these large areas vacated prior to
construction will facilitate the process by allowing the renovation to be completed in one area
before a department is relocated to its new permanent office space, opening the next area for
construction.
There are costs associated with staging a renovation project in this fashion. Construction
moves slower, so the fixed monthly costs to the contractor, collectively known as general
conditions costs, are greater. Although precautions are taken, there is greater risk that an
employee of the county or a member of the public could be injured as the result of construction
activity, so insurance premiums are a little higher. There is no easy way to demolish the heating,
ventilating and air conditioning (HVAC) system and install a new one without affecting the
offices served. This study anticipates the contractor renting and installing, and eventually
removing, a temporary HVAC system to condition occupied spaces during the transition from
the buildings old to new mechanical system.
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Opinion of Cost
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Opinion of Renovation Cost
Howard R. Green Company has prepared a preliminary opinion of construction cost for the
renovation of Linn County West into permanent County offices. Assumptions underlying our
opinion of the cost of the work are discussed in the sections of this study titled Renovation
Scope and Sequence of Work. Table 3 provides a detail summary of the opinion of
construction cost.
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Table 3: Preliminary Opinion of Construction Cost
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Annual Energy Costs
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Anticipated Annual Energy Costs
The energy costs for operating a building are estimated using the actual rates charged by
utilities applied to a building model that simulates the consumption of electricity and gas to heat,
cool, ventilate, light and operate incidental equipment in the building. For budgeting and
comparison purposes these costs are typically aggregated as annual costs.
HR Green utilized the Carrier E20-II load calculation and simulation program to estimate energy
usage and costs for the Linn County West building over a period of one year. The building
model incorporated the proposed new mechanical and electrical systems discussed in this
report and also included all proposed architectural changes. The following assumptions were
also used in the analysis.
Only office equipment plug loads were included in the analysis. Office equipment plug
loads included computers, monitors, printer & copiers. Computers and monitors were
assumed to be in sleep/stand-by mode during hours when the building in unoccupied.
Space usage and occupancy levels are similar to the current layout at Linn County West.
Offices were assumed to be occupied from approximately 8am to 5pm, Monday through
Friday and conference rooms were assumed to be occupied sporadically throughout the
day.
Lighting levels were set at 0.75 watts per square foot.
Entrance snow melting energy usage was not included in the analysis.
Exterior lighting and elevator electrical usage were not included in the analysis.
Building temperatures set points of 74/80 were used for occupied/unoccupied periods
during the summer and 70/64 during the winter.
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Linn County West Feasibility ReportSeptember 22, 2009
Electric rates used were for Large General Service from Interstate Power and Light
Company as listed in the Electric Tariff dated March 17, 2009.
Gas rate - $1.00 per therm.
Historical weather data for Cedar Rapids was input to simulate average weather
conditions for the entire year.
Using these assumptions, the annual energy cost for the renovated Linn County West building
is estimated to be approximately $77,500 per year. The complete energy usage and costs
report is found in Appendix B.
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Life Cycle Analysis
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Linn County West Feasibility ReportSeptember 22, 2009
Life Cycle Analysis
A life cycle cost is a number representing the cost of owning and operating a building over a set
period of time for the purpose of comparing different buildings or different building strategies.
Calculation of the life cycle cost considers the initial investment in construction costs, the cost of
energy to operate the building, the cost of maintenance and effect of inflation on those costs
over the life period. These costs are distilled into a single index called the total present worth.
By itself, the calculated total present worth is not a very meaningful number; it becomes
meaningful when compared to the total present worth of an alternate that has been analyzed
using similar assumptions.
HR Green utilized the Carrier Engineering Economic Analysis program to determine the life
cycle cost of the Linn County West Building. The estimated annual energy costs were imported
from the annual energy use analysis. Increases in energy, labor and material costs over time
are estimated by using escalation rates to inflate future costs. In order to perform the analysis
the following assumptions were used.
Length of Analysis 25 years
Discount Rate 4 %
Energy Costs Escalation Rate 2.6 %
Maintenance Cost Escalation Rate 1.8 %
Equipment Cost Escalation Rate 1.8 %
HVAC system maintenance costs were calculated in accordance with the 1999 ASHRAE
Applications Handbook Chapter 35 and the ASHRAE Owning and Operating Cost
Database based on ASHRAE Research Project 1237-TRP.
Equipment Useful Life Obtained from ASHRAE useful life data
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Linn County West Feasibility ReportSeptember 22, 2009
Annual common area maintenance (CAM) Fee of $50,000 per year
The life cycle cost analysis estimated the total present worth of the Linn County West building to
be $19,409,030. The total present worth is the combination of the estimated initial construction
cost of $15,289,000 and the estimated annual operating cost of $207,360. Operating expenses
for each year of the analysis are discounted into todays dollars using the discount rate in order
to calculate the total present worth. The life cycle cost report is found in Appendix C.
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Linn County West Feasibility ReportSeptember 22, 2009
Summary
Extensive work is required to adapt the former Montgomery Wards department store into
permanent County offices. Only the buildings frame, floor slabs, roof decking and side-wall
back-up framing are salvageable for re-use.
The Linn County West renovation project can achieve a LEED Silver certification in support of
the Countys green building initiative.
The renovation can be sequenced so that County offices currently housed at Linn County West
and intended to remain there can remain open to the public throughout the construction period,
provided that the offices intended for relocation to other sites have completed their transitions.
Howard R. Green Company has developed a preliminary opinion of construction costs for the
renovation totaling $15,289,000.
Annual energy costs are expected to be about $77,500 for the renovated building.
The current annual Common Area Maintenance (CAM) fees are about $50,000. If Linn County
elects to pursue renovation of Linn County West, then the CAM fees should be renegotiated to
better reflect the how the County is or is not benefitted by the amenities supported by the fees.
A life cycle cost analysis results in Linn County West having a calculated total present worth of
about $19,409,000.
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Appendix A
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Appendix B
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Annual Component Costs - Linn County WestLinn County - Feasibility Study Model 09/21/2009Howard R. Green Company 11:28AM
10.1%Air System Fans
9.4%Cooling
9.6%Heating
5.2%Pumps
5.6%Cooling Tower Fans36.4% Lights
22.6% Electric Equipment
1.1% Misc. Electric
1. Annual Costs
Component
Annual Cost
($) ($/ft)
Percent of Total
(%)Air System Fans 7,784 0.069 10.1
Cooling 7,248 0.064 9.4
Heating 7,445 0.066 9.6
Pumps 4,011 0.036 5.2
Cooling Tower Fans 4,341 0.039 5.6
HVAC Sub-Total 30,829 0.274 39.8
Lights 28,161 0.250 36.4
Electric Equipment 17,495 0.155 22.6
Misc. Electric 879 0.008 1.1
Misc. Fuel Use 0 0.000 0.0
Non-HVAC Sub-Total 46,535 0.413 60.2
Grand Total 77,364 0.687 100.0
Note: Cost per unit floor area is based on the gross building floor area.
Gross Floor Area 112683.0 ftConditioned Floor Area 112683.0 ft
Hourly Analysis Program v.4.4 Page 1 of 1
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Annual Energy Costs - Linn County WestLinn County - Feasibility Study Model 09/21/2009Howard R. Green Company 11:28AM
30.2%HVAC Electric
9.6%HVAC Natural Gas
60.1% Non-HVAC Electric
1. Annual Costs
ComponentAnnual Cost
($/yr) ($/ft)Percent of Total
(%)
HVAC Components
Electric 23,384 0.208 30.2
Natural Gas 7,444 0.066 9.6
Fuel Oil 0 0.000 0.0
Propane 0 0.000 0.0
Remote Hot Water 0 0.000 0.0
Remote Steam 0 0.000 0.0
Remote Chilled Water 0 0.000 0.0
HVAC Sub-Total 30,829 0.274 39.9
Non-HVAC Components
Electric 46,532 0.413 60.1
Natural Gas 0 0.000 0.0
Fuel Oil 0 0.000 0.0
Propane 0 0.000 0.0
Remote Hot Water 0 0.000 0.0
Remote Steam 0 0.000 0.0
Non-HVAC Sub-Total 46,532 0.413 60.1
Grand Total 77,361 0.687 100.0
Note: Cost per unit floor area is based on the gross building floor area.
Gross Floor Area 112683.0 ftConditioned Floor Area 112683.0 ft
Hourly Analysis Program v.4.4 Page 1 of 1
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Monthly Component Costs - Linn County WestLinn County - Feasibility Study Model 09/21/2009Howard R. Green Company 11:28AM
0
500
1000
1500
2000
2500
Cost($)
MonthJan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Air System Fans Cooling Heating Pumps
Cooling Tower Fans Lights Electric Equipment Misc. Electric
1. HVAC Component Costs
Month Air System Fans($) Cooling($) Heating($) Pumps($) Cooling Towers($) HVAC Total($)
January 417 49 2,343 17 0 2,826
February 372 48 1,425 15 0 1,860
March 394 246 880 300 48 1,868
April 404 274 185 286 109 1,258
May 609 594 7 404 425 2,039
June 1,232 1,479 0 706 986 4,403
July 1,403 1,859 0 817 1,179 5,258
August 1,241 1,598 0 704 970 4,513
September 571 639 7 406 424 2,047
October 410 361 243 325 200 1,539
November 339 51 649 14 0 1,053
December 392 50 1,706 16 0 2,164
Total 7,784 7,248 7,445 4,011 4,341 30,829
2. Non-HVAC Component Costs
MonthLights
($)
ElectricEquipment
($)Misc. Electric
($)Misc. Fuel Use
($)Non-HVAC Total
($)Grand Total
($)
January 2,263 1,438 69 0 3,770 6,596
February 2,277 1,406 72 0 3,754 5,614
March 2,213 1,352 70 0 3,634 5,502
April 2,148 1,317 68 0 3,533 4,791
May 2,092 1,311 65 0 3,468 5,507
June 2,806 1,719 89 0 4,614 9,017
July 2,610 1,636 81 0 4,327 9,585
August 2,796 1,729 88 0 4,613 9,126
September 2,121 1,317 66 0 3,504 5,551
October 2,184 1,369 68 0 3,621 5,160
November 2,295 1,445 71 0 3,810 4,863
December 2,357 1,458 74 0 3,888 6,052
Total 28,161 17,495 879 0 46,535 77,364
Hourly Analysis Program v.4.4 Page 1 of 1
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Monthly Energy Costs - Linn County WestLinn County - Feasibility Study Model 09/21/2009Howard R. Green Company 11:28AM
0
500
1000
1500
2000
2500
3000
3500
4000
4500
5000
5500
Cost($)
MonthJan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
HVAC Electric HVAC Natural Gas Non-HVAC Electric
1. HVAC Costs
MonthElectric
($)Natural Gas
($)Fuel Oil
($)Propane
($)
Remote HotWater($)
Remote Steam($)
Remote ChilledWater($)
January 484 2,343 0 0 0 0 0
February 435 1,425 0 0 0 0 0
March 989 880 0 0 0 0 0
April 1,072 185 0 0 0 0 0
May 2,032 7 0 0 0 0 0
June 4,403 0 0 0 0 0 0
July 5,258 0 0 0 0 0 0
August 4,513 0 0 0 0 0 0
September 2,040 7 0 0 0 0 0
October 1,297 243 0 0 0 0 0November 404 649 0 0 0 0 0
December 458 1,706 0 0 0 0 0
Total 23,384 7,444 0 0 0 0 0
2. Non-HVAC Costs
MonthElectric
($)Natural Gas
($)Fuel Oil
($)Propane
($)
Remote HotWater
($)Remote Steam
($)
January 3,770 0 0 0 0 0
February 3,754 0 0 0 0 0
March 3,634 0 0 0 0 0
April 3,532 0 0 0 0 0
May 3,467 0 0 0 0 0June 4,613 0 0 0 0 0
July 4,326 0 0 0 0 0
August 4,613 0 0 0 0 0
September 3,504 0 0 0 0 0
October 3,621 0 0 0 0 0
November 3,810 0 0 0 0 0
December 3,888 0 0 0 0 0
Total 46,532 0 0 0 0 0
Hourly Analysis Program v.4.4 Page 1 of 1
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Appendix C
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Lifecycle SummaryProject: Linn County - Feasibility Study Model 9/22/2009Prepared By: Howard R. Green Company 9:56:32 AM
Linn County West Life Cycle Cost Analysis
The purpose of this life cycle cost analysis is to determine the total present worth of the Linn County West Building. Theanalysis includes the estimated initial construction cost, annual maintenance cost and annual energy costs.
Type of Analysis Public Sector Lifecycle AnalysisType of Design Alternatives Mutually ExclusiveLength of Analysis 25 yrs
Discount Rate 4.00 %
Table 1. Executive Summary
Economic Criteria Best Design Case for Each Criteria Value ($)
Incremental SIR Analysis Linn County West -
Lowest Total Present Worth Linn County West $19,409,032
Lowest Annual Operating Cost Linn County West $207,360
Lowest First Cost Linn County West $15,289,000
Table 2. Design Cases Ranked by First CostDesign Case Name Design Case
Short NameTotal Present
Worth ($)Annual Operating
Cost ($/yr)First Cost ($)
Linn County West LCW $19,409,032 $207,360 $15,289,000
Table 3. Incremental Analysis DataChallenger Base Case Additional
First Cost ($)NPW Savings
($)SIR Payback
Period (yrs)
LCW [Winner] LCW [Winner] $0 $0 0.000 n/a
Engineering Economic Analysis v 3.0 Page 1 of 1
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Cash Flow DetailsProject: Linn County - Feasibility Study Model 9/22/2Prepared By: Howard R. Green Company 9:56:43
Linn County West Life Cycle Cost Analysis
The purpose of this life cycle cost analysis is to determine the total present worth of the Linn County West Building. The analysis includes the estimated initialconstruction cost, annual maintenance cost and annual energy costs.
Type of Analysis Public Sector Lifecycle Analysis