mass timber learning series · mass timber learning series – seagate mass timber quality +...

MASS TIMBER LEARNING SERIESJULY/AUGUST 2019

MASS TIMBER LEARNING SERIES – SEAGATE MASS TIMBER QUALITY + INTEGRITY

WOOD FRAME/CROSS LAMINATED TIMBER (CLT) HYBRID BUILDINGS-up to 6 storeys

PROS:•Easier, better, faster

•Can be done under existing building codes

•Gravity system is the same - wood frame walls

•Lateral system is the same - wood shearwalls and holddowns

•Easy for framing contractors to learn to do

•Removing the stick-framed floors and replacing with CLT panels takes away a lot of complexity

•Faster schedule

•Cleaner during construction; no clutter


PROS CONT’D:

• Not much change to other trades’ work vs conventional framing.

• Holes for mechanical can be factory pre-drilled in CLT panels.

• Ceilings can be left exposed if desired.

• Many architect and engineers are familiar and comfortable with this building type.

• Ideal for projects that stack all the way up.

• Thinner floors allow for higher ceiling heights.

• Can source panels from Europe to help get competitive prices.

• New local CLT plants are coming online in B.C. and Washington State which will provide better competitive prices.

• Can use CLT for elevator shafts and firewalls to eliminate the blockwork trade (and the mess and schedule issues that comes with them).

• CLT floors are much safer during the course of construction vs TJI’s from a fire risk perspective.


CONS:

• More expensive per SF than conventional framing with TJI floors

• Much more expensive per SF if ceilings are to be exposed

• Need to use 3 ply CLT to remain cost competitive so ceilings would need 2 layers of 5/8” fireguard drywall

• Maximum spans about 13-0

• No floor cavities to run services so MEP can be challenging

• Procurement is longer – 12 weeks after approved shop drawings, which in turn is 6 weeks after IFC drawings – So 18 weeks in total from IFC to panels on site

• Limited number of local CLT manufacturers

• Crane time can be an issue

• Load transfers are problematic

• Cantilevered balconies and roof overhangs are not recommended. Balconies ideally should have corner posts

• Vibration and acoustics need to be considered and special attention paid to assemblies


SCHEDULE BENEFITS

• Can easily achieve 8,000 SF per week with a normal sized framing crew and one crane vs about 5,000 SF per week with a large framing crew when doing conventional framing.

• On a 120,000 SF building using CLT floors and roofs can reduce the schedule to get the roofer started from 24 weeks to 15 weeks - about 2 months earlier.

• The general contractor will need to effectively manage the trades through to the end to realize the schedule savings.


ECONOMICS• Lumber, including HD system, is currently about $28 to $30 per SF for conventional apartment framing.

• Remove TJI floors and roof - Deduct $5 per SF.

• Use 3 ply CLT floors and Roof - Add about $15 per SF (for North American Supply).

• Framing Labour Savings – Deduct $1.50 per SF.

• Total Change – Add $8.50 per SF.

• So Lumber and Labour including HD system is currently about $36.50 to $38.50 per SF for CLT/Wood Frame Hybrid.

• The cost for a 5-ply CLT/Wood Frame Hybrid would currently be about $7.00 more per SF - about $42.50 to $45.50 per SF.

• Using European panels would save about $5.00 per SF.


MID-RISE TIMBER BUILDINGS - 6 TO 12 STOREYSPROS• Easier, Better, Faster and Cheaper

• B.C. Building Code has changed to allow Mass Timber construction up to 12-storeys and it is being adopted municipality by municipality.

• Competes very well vs cast-in-place concrete on cost per SF.

• Much smaller crew size with little to no overtime or weekend work

• Materials are precision prefabricated off site and delivered on just-in-time basis, off the truck and into place.

•High degree of accuracy; +/- 2mm.

• Very little laydown area is required.

• 80% fewer deliveries.

• Low impact on neighbourhoods. Much less traffic, trade parking and noise.

• Cleaner, safer, faster.


• Local architects, engineers and code consultants are gaining experience and knowledge and are quickly becoming some of the best in the world for Mass Timber design.

• Mass Timber buildings are very durable and have been proven to perform very well in seismic conditions.

• Next generation of seismic systems for mass timber buildings will allow buildings to return to their original condition after the seismic event has ended with very little structural repair required.

• Erection schedule is much faster than other building methods; 20,000 SF per week is possible; 10,000 SF per week is most common.

PROS CONT’D:


• Follow up trades can work on the floor below the active floor. No reshore is required

• Building with Mass Timber reduces the embed carbon in the building construction when compared to building with other materials.

• Wood sequesters carbon during the life of the building

• Able to expose much of the structure and meet code requirements

• Aesthetics of exposed wood is a major feature for owners and clients

• Because the 3D model for the Mass Timber elements helps resolve conflicts with other building elements and systems there is a great reduction in the number of RFI’s, Site Instructions and Change Order Requests once construction starts

PROS CONT’D:


CONS:

• Municipalities and AHJ are slow to adopt new BC Code changes

• Cost driver is volume of wood

• Longer spans and cantilevers require a larger volume of wood and so long spans are problematic for economics

• Lateral systems using wood are not yet economical

• Concrete or structural steel are still the best materials for the lateral system so that requires a mixed crew on site that need to share a crane and coordinate their activities

• Moisture or staining during construction issues need to be addressed

• Fire protection measures during construction need to be addressed

• Limited number of local CLT manufacturers

• Limited number of local timber contractors and general contractors that are familiar with Mass Timber construction

• MEP trades are not familiar with Mass Timber construction and may bid with a premium when they should be bidding with a discount

• Mass timber construction is very fast and 20,000 SF per week is possible, but it is not easy for other trades to keep up to that pace


SCHEDULE BENEFITS· Construction can be done extremely fast

· The 3D model that is done in advance of the shop drawings outputs the truck loading plan that drives the installation sequence. So essentially the building is built in advance of starting on site. On Day 1 it is “Go Time”.

· Very little to no overtime work

· Very little to no Saturday work

· Days are done by 4PM

· Other trades can start early – on the floor below the active floor

· Building envelope can be done right up to under the active floor

· The GC needs to be extremely organized to maintain the schedule gain through to the end of the project


ECONOMICS• Competes very well vs CIP concrete or structural steel

• 20 -0 x 20-0 column grids are best with 1 hr FRR between floors

• Volume of wood is the cost driver

• Longer spans require deeper beams and/or more beams and/or deeper panels so cost per SF goes up

• If 2 hr FRR is required between floors, panels and thicker and cost per SF goes up

• Rough Costs per SF • 20x20 column grids with 1 hr FRR - $35 to $40 per SF • Larger column grids or 2hr FRR - $40 to $50 per SF • Larger column grids and wood lateral system - $50 to $60 per SF • Larger column grids, wood lateral system, high floors, complex - $60 to $70 per SF

• There could be cost savings if European Mass Timber products are used


PROCUREMENT STRATEGIES FOR MASS TIMBERMASS TIMBER ELEMENTS TO PROCURE

• 3D Model and fabrication model

• Specialty engineering if required • concept lab by Fast + Epp

• Glulam Columns and Beams

• Floor Panels • CLT – Cross Laminated Timber • NLT – Nail Laminated Timber • GLT – Glue Laminated Timber • DLT – Dowel Laminated Timber • MPP – Mass Plywood Panels

• Fabrication

• Wood to wood connections

• Screws

• Delivery

• Installations

Project:Fast Epp+Suite 2011672 West 1st AveVancouver BCCanada V6J 1G1

T 604 731 7412F 604 731 [email protected]

Copyright reserved. This drawing and design is and at alltimes remains the exclusive property of Fast+Epp andcannot be used without their written consent and associateddisclaimer fees. The information contained herein is for useof the Client only. Fast+Epp is under no obligation to supplyelectronic/computer files for this project to the Contractor orSubcontractors. Fast+Epp and its employees are not liableto any other parties relating to the use of these drawings.

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Ref. Dwg.:CS-S00

OFFICE MODULE - CONCEPT OVERVIEW

DESIGN ASSUMPTIONS:- 50 PSF SUPERIMPOSED DEAD LOAD- 50 PSF LIVE LOAD- 1HR FRR. ALL ELEMENTS DESIGNED TO CHAR- 4 FLOORS @ ~14' HEIGHT.- ASSUME RAISED FLOOR SYSTEM WHICH CARRIESSUPPLY AIR, ELEC., COMM., PLUMBING. - ASSUME SPRINKLERS AND RETURN AIR DUCTSEXPOSED IN CEILING.

30'X30'

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30'

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GL GL

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25'

25'

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25'X25'

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25'X20'

CS-S01 TO CS-S10 CS-S11 TO CS-S20 CS-S21 TO CS-S23

https://www.fastepp.com/concept-lab/


STRATEGIES FOR SUCCESSFUL PROCUREMENT• Engage timber contractor early

• Collaboration with design team to provide input on design and connections

• Get to price certainty early

• Decide if European products are in play and if so guide the design to allow for Mass Timber product sizes that are most economically shipped – 7-2 wide x 39-6 long maximum

• Engage specialty engineer if required

CLT Panel Suppliers

Supplier Location (mm) (ft) (mm) (ft) CommentsCANADAStructurlam Penticton, BC 3048 10.0 12190 40.0Nordic Montreal, QC 2440 8.0 19500 64.0

DR Johnson Riddle, OR 3048 10.0 9146 30.0Smartlam Whitefish, MT 3200 10.5 12217 40.1

KLH Austria 2950 9.7 16500 54.1 Have floor panel and wall panels differentiated. Wall panels with visual quality must be specified. MERK Germany 4800 15.7 14800 48.6 Many options avaliable.

Derix Germany 3500 11.5 17800 58.4Have floor panel and wall panels differentiated. Wall panels are non-visual outer layers unless otherwise specified.

BinderHolz Austria 1250 4.1 24000 78.7

Floor panel max width is 1250. Wall panel max width is 3500 (outer layers crosswise). Can get 3500 wide floor panels w/ longitudinal boards, but non-visual grade. Perhaps special order ok for visual, longitudinal?

StoraEnso Austria 2950 9.7 16000 52.5 Have floor panel and wall panels differentiated

USA

EUROPE

Max Width Max Length

• Engage 3D modeller

• Get multiple quotes for Mass Timber products, connections and screws

• Allow adequate lead time for procurement of products whether local or international


MASS TIMBER CONSTRUCTION CAN DRAMATICALLY CHANGE HOW WE BUILD OUR CITIES.Buildings that have Mass Timber as the main structural element are better for the environment, better for the workers that build them and better for the people that live and work in them.

mass timber learning series · mass timber learning series – seagate mass timber quality +...

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