NRCan Screening Tool for New Building Design:

Small Office Archetype

Expectations for Energy Efficiency MeasuresStephen Pope, OAA, FRAIC

Sustainable Building Design Specialist11nov09

2

Agenda

What we know when “we don’t know anything”;Establishing expectations for energy efficiency;

Small Office Archetype – 8 Canadian Cities.

Hands-on review.Photo: Lyse Tremblay architecte

3

“…when you don’t know anything…”

Performance assessment starts as soon as one knows:

Building type; Gross Wall Area, Gross Roof Area, and Gross conditioned floor area.

Canadian Energy Use Surveys:National (Comprehensive) End-Use Database (NEUD / CEUD);http://oee.nrcan.gc.ca/corporate/statistics/neud/dpa/comprehensive_tables/index.cfm?attr=0

Model National Energy Code for Buildings ‘97, Part 8:Former CBIP tools and guides (EE4, Screening Tool).

4

NEUD

5

Whole Building Energy Simulation

NRCan Screening Tool for New Building Design;Parametric editor based on over 100,000 DOE 2.1e runs;28-32 data entry points;Follows MNECB Part 8 + CBIP rules;Selection of building archetypes available;Selection of mechanical systems available.http://screen.nrcan.gc.ca/

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Architecture Sets the Energy Context

Fenestration / Shading

Electric Lighting Demand

Occupancy &

Conditioned Floor Area

Potable water demand

Air heating demand

Air cooling demand

Form & Orientation

Space cooling demand

Space heating demand

Communications & power demand

Ventilation demand

Skin Heat Loss

Skin Heat Gain

Whole Building Site Energy

Demand

Note: Site climate determines the general magnitude of each end-use.

In-building pumping

7

Small Office Archetype

4,010 m2 conditioned floor area over 3 stories;1:1 plan aspect ratio, 1.2:1 wall-to-roof area ratio, 36.5 m perimeter length per side; 1,338 m2 roof area; 1,604 m2 wall area; 0.4 fenestration-to-wall ratio;0.4 L/s/m2 Outdoor Air; 7.5 W/m2 plug load; 25 m2/person occupant load; 18 W/m2 connected lighting power density; 90 W/person SHW load;Plant: 80% thermal efficiency natural gas boiler; COP 3.8 electric chiller.

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The Small Office Archetype

MethodOne common building type reviewed with a common approach to energy

efficiency in 3 basic scenarios.

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Starting points: MNECB Reference

2.442.080.7363.2Halifax

3.453.030.7362.1Montreal2.131.820.7363.2Toronto

2.862.700.7362.1Winnipeg

2.442.080.7363.2Regina

2.131.820.7363.2Calgary

3.452.70.7362.1Whitehorse

2.131.230.7363.2Vancouver

Roof Insulation RSI (m2*oC/W)

Wall Insulation RSI (m2*oC/W)

Window shading coefficient (SC)

Window U value (W/m2*oC)

Location

11

Energy Efficiency Measures: Boilers

Boiler Upgrades: starting at 80% reference efficiency w/ on-off controls, upgrade to:

85% eff, on-off; 85% eff, modulating; 90% eff, modulating; 92% eff, modulating; 92% eff, condensing; 95% condensing.

12

EE Measures: Windows

Fenestration-to-wall ratio: Starting at 40%, increase area by 5% steps to 95%;Window performance values: Starting at U=3.2 (or 2.1) and SC=0.736 (SHGC 0.846) decrease U and SC with the following range:

CLR-CLR, air, alum spcr, FG frm: U=2.79/SC=0.61;CLR-LE, argon, alum spcr, TB alum frm: U=2.55/SC=0.59;CLR-LE, argon, TB spcr, TB alum frm: U=2.45/SC=0.59;CLR-LE, argon, alum spcr, FG frm: U=1.89/SC=0.56;CLR-LE, argon, TB spcr, FG frm: U=1.82/SC=0.56; CLR-LE(TiR), argon, alum spcr, FG frm: U=1.68/SC=0.41; CLR-LE(TiR), argon, TB spcr, FG frm: U=1.61/SC=0.41;CLR-CLR-LE, air-argon, 2 TB spcr, FG frm: U=1.3/SC=0.5;CLR-LE-LE, argon-argon, 2 TB spcr, FG frm: U=1.1/SC=0.46;CLR-LE-LE (TiR), argon-argon, 2 TB spcr, FG frm: U=0.94/SC=0.31.

13

EE Measures: Envelope

Based on reference building using lowest ESAF heating fuel (natural gas everywhere but Quebec).

Wall insulation: Starting at the reference increase insulation value in increments of RSI 0.5 to RSI 7.5;

Roof insulation: Starting at the reference increase insulation value in increments of RSI 0.5 to RSI 7.5, then show RSI 10 and RSI 15;

14

EE Measures: Lighting and HRVs

Lighting: Starting with the reference at 18 W/m2

CLPD, reduce to 15, 12, and 10 W/m2; Then reduce by increments of 0.5 W/m2 to 4 W/m2;

Heat recovery ventilation: Increase the effectiveness (machine efficiency times relative volume of relief or exhaust air) in increments of 5% from 0 to 60%, then show 80% effectiveness.

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Small Office Charts Comparisons

For each of the 8 Cities:MNECB compared to NEUD;Ventilation energy demand compared to skin loss energy demand;Individual measure performance against whole building annual energy consumption;FWR mapped against window performance.

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Options PresentedPerformance Curves:

MNECB Reference System for multi-zone buildings (Variable Air Volume - VAV);Ventilation Separated from heating and cooling, showing ventilation by dedicated outdoor air system (DOAS – more commonly make-up air units –MUA), represented a four-pipe fan coil system (4PFC);Note: Performance curves are sensitive to building occupancy, geometry, roof-to-wall area ratio, HVAC System, and location. The curves are specific to the model described.

Fenestration Tables:Typical approach to minimum measures required to achieve LEED Ca-NC Energy & Atmosphere prerequisite 2;Specific approach to a high-performance office showing double occupancy and double plug loads.

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LEED® Ca-NC EAp2 in 3 Steps

Ventilation air supply separated from heating and cooling (fan coil HVAC system);Reduced connected lighting power densities (9.0 W/m2) with occupancy sensor and daylighting dimming controls for light fixtures over 30% of floor plate;Condensing space heating boiler (modulating boiler for some regions).Occupancy sensor controlled DCV for all floor areas (option for Vancouver only).

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High Performance Small Office

1. Concentrated Occupancy:Double MNECB Occupant Density (13m2/occupant);Double MNECB receptacle power allowance (15 W/m2).

2. Separated ventilation air supply from heating and cooling;

3. Low-energy hydronic radiant heating and cooling;4. Reduced connected lighting power densities (9.0

W/m2); 5. Occupancy and daylighting dimming controls for light

fixtures;6. Heat recovery on exhaust or relief air; 7. Demand controlled ventilation (may swap rank w/ 6); 8. Condensing space heating boilers;9. Improved window thermal performance values;

Thunder Bay

20

260

280

300

320

340

360

380

400

420

440

460

1998 1999 2000 2001 2002 2003 2004 2005 2006

ekW

h / s

q.m

/ yr

.NEUD Compared to MNECB

NEUD Historic Data – Offices Ontario

MNECB 97 Small Office Thunder Bay

MNECB 97 Large Office Thunder Bay

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010,00020,00030,00040,00050,00060,00070,00080,00090,000

100,000110,000120,000130,000140,000150,000160,000170,000180,000190,000200,000210,000220,000230,000

500 1,000 1,500 2,000 2,500 3,000 3,500 4,000 4,500 5,000 5,500

Floor Area (m2)

Hea

t Req

uire

d (W

)

Skin Loss MNECB Office Ventilation Multi-res Ventilation

Skin Heat Loss vs. Ventilation 1

Base Case: MNECB Reference Building for Ontario Region B

3 Storey Small Office Gas Heat VAV DistributionFWR 40%RSI 2.4 RoofRSI 2.1 WallsRSI 0.35 Windows

Winter design day skin loss is 59% of total heating load for 4,000 m2 office.

Skin loss

MNECB Office Ventilation

MNECB MURB Ventilation

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010,00020,00030,00040,00050,00060,00070,00080,00090,000

100,000110,000120,000130,000140,000150,000160,000170,000180,000190,000200,000210,000220,000230,000

500 1,000 1,500 2,000 2,500 3,000 3,500 4,000 4,500 5,000 5,500

Floor Area (m2)

Heat

Req

uire

d (W

)

Skin Loss MNECB Office Ventilation Multi-res Ventilation

Skin Heat Loss vs. Ventilation 2Advanced Case: MNECB Proposed Building for Ontario Region B

3 Storey Small Office Gas Heat VAV DistributionFWR 40%RSI 3.5 RoofRSI 3.5 WallsRSI 1.0 Windows

Winter design day skin loss is 40% of total heating load for 4,000 m2 office.

Skin loss

MNECB Office Ventilation

MNECB MURB Ventilation

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Thunder Bay Reference

Thunder Bay Small Office w/ VAV - Envelope & Lighting

2,800

3,000

3,200

3,400

3,600

3,800

4,000

4,200

4,400

4,600

4,800

5,000

5,200

5,400

5,600

5,800

6,000

6,200

6,400

Ener

gy C

onsu

mpt

ion

(GJ)

FWR 40% - 95%

MNECB+CBIP Reference

LEED Canada NC EAp2Window U 3.2 – 0.94

CLPD 18 – 4 W/m2

Wall RSI 2.1 – 7.5Roof RSI 2.4 – 15

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Thunder Bay 4PFC Reference

Thunder Bay Small Office w/ 4PFC - Envelope & Lighting

2,800

3,000

3,200

3,400

3,600

3,800

4,000

4,200

4,400

4,600

4,800

5,000

5,200

5,400

5,600

5,800

6,000

6,200

6,400

Ener

gy C

onsu

mpt

ion

(GJ)

FWR 40% - 95%

MNECB+CBIP Reference

LEED Canada NC EAp2Window U 3.2 – 0.94

CLPD 18 – 4 W/m2 Wall RSI 2.1 – 7.5

Roof RSI 2.4 – 15

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Thunder Bay vs. Toronto

Thunder BayMNECB Ontario Region B;5650 Degree Days below 18oC;Monthly average hours of bright sunshine: 91.7Small Office MNECB Reference annual energy consumption: 3,994 GJ;Reference Values:

Windows: U = 3.2 W/m2oCWalls: RSI = 2.1 W/m2oCRoof: RSI = 2.4 W/m2oC

TorontoMNECB Ontario Region A;3650 Degree Days below 18oC;Monthly average hours of bright sunshine: 74.7Small Office MNECB Reference annual energy consumption: 3,636 GJ;Reference Values:

Windows: U = 3.2 W/m2oCWalls: RSI = 1.8 W/m2oCRoof: RSI = 2.1 W/m2oC

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Toronto Small Office w/ VAV - Envelope & Lighting

2 700

2,900

3,100

3,300

3,500

3,700

3,900

4,100

4,300

4,500

4,700

4,900

5,100

5,300

5,500

5,700

Ener

gy C

onsu

mpt

ion

(GJ)

Identify EE measure limits

FWR 40% - 95%

MNECB+CBIP Reference

LEED Canada NC EAp2

Window U 3.2 – 0.94

CLPD 18 – 4 W/m2

Wall RSI 1.8 – 7.5

Roof RSI 2.1 – 15

Thunder Bay @ 3994 GJ

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Archetype Toronto Small Office w/ 4PFC - Envelope & Lighting

2 500

2,700

2,900

3,100

3,300

3,500

3,700

3,900

4,100

4,300

4,500

4,700

Ener

gy C

onsu

mpt

ion

(GJ)

Impact of DOAS

FWR 40% - 95%

MNECB+CBIP Reference

LEED Canada NC EAp2

Window U 3.2 – 0.94 CLPD 18 – 4 W/m2

Wall RSI 1.8 – 7.5

Roof RSI 2.1 – 15

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System ImpactsToronto Small Office w/ VAV - Envelope & Mechanical

3,300

3,400

3,500

3,600

3,700

3,800y

Con

sum

ptio

n (G

J)

Toronto Small Office w/ 4PFC - Enevelope & Mechanical

2,900

3,000

3,100

3,200

3,300

3,400

3,500

3,600

Ener

gy C

onsu

mpt

ion

(GJ)

Roof RSI 2.4 – 15

Roof RSI 2.1 – 15

Wall RSI 1.8 – 7.5

Boiler Eff 80% - 95%

Boiler Eff 80% - 95%HRV Eff 5% - 80%

HRV Eff 5% - 80%

Wall RSI 1.8 – 7.5

MNECB+CBIP Reference

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FWR for Small Office with VAV

-6-214710121517202224TG / U0.94 / SC 0.31-12-8-5-12581013161820TG / U1.10 / SC 0.46 -15-12-8-5-125811131618TG / U1.30 / SC 0.50-17-13-9-6-214710131618DG / U1.62 / SC 0.41-18-14-10-7-304710131518DG / U1.68 / SC 0.41-24-20-16-12-8-5-12581114DG / U1.82 / SC 0.56-25-21-17-13-9-5-21581113DG / U1.89 / SC 0.56-35-30-25-21-16-12-8-5-1369DG / U2.45 / SC 0.59-36-31-26-22-18-13-9-6-2258DG / U2.55 / SC 0.59-41-36-31-26-21-17-13-8-5-136DG / U2.79 / SC 0.61-51-46-40-35-30-25-20-16-12-8-40DG / U3.2 / SC 0.74

95%90%85%80%75%70%65%60%55%50%45%40%Window / FWR

Perc

ent e

nerg

y re

duct

ion

from

MN

ECB

FWR & SC w/ MNECB Reference satisfies LEED Ca-NC EAp2Expansion of FWR allows some flexibility with trade-offsExpansion of FWR doesn’t compromise benefits of other strategiesExpansion of FWR compromises benefits of other strategiesFWR & SC w/ MNECB Reference values fail to satisfy MNECB

Toronto Small Office archetype

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FWR for Small Office & 4PFC

7911141618202224262830TG / U0.94 / SC 0.31469111316182022242627TG / U1.10 / SC 0.46 14691114161820222426TG / U1.30 / SC 0.50

-3036811131618202224DG / U1.62 / SC 0.41-4-125810131517202224DG / U1.68 / SC 0.41-4-30368111315182022DG / U1.82 / SC 0.56-7-4-1257101215171922DG / U1.89 / SC 0.56

-15-12-8-5-214710121517DG / U2.45 / SC 0.59-17-13-10-6-30369111416DG / U2.55 / SC 0.59-20-17-13-9-6-303691214DG / U2.79 / SC 0.61-26-22-18-16-13-9-6-30369DG / U3.2 / SC 0.74

95%90%85%80%75%70%65%60%55%50%45%40%Window / FWR

Perc

ent e

nerg

y re

duct

ion

from

MN

ECB

FWR & SC w/ MNECB Reference satisfies LEED Ca-NC EAp2Expansion of FWR allows some flexibility with trade-offsExpansion of FWR doesn’t compromise benefits of other strategiesExpansion of FWR compromises benefits of other strategiesFWR & SC w/ MNECB Reference values fail to satisfy MNECB

Toronto Small Office archetype

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FWR & LEED™ Ca-NC EAp2

222427293133353739414344TG / U0.94 / SC 0.31202225272732343638394143TG / U1.10 / SC 0.46 172022252729323436384042TG / U1.30 / SC 0.50121518212326283133353739DG / U1.62 / SC 0.41111417202225273032343739DG / U1.68 / SC 0.41101316192124262931333538DG / U1.82 / SC 0.5691215182023262830333537DG / U1.89 / SC 0.56047101317192225283032DG / U2.45 / SC 0.59

-22691215182124272931DG / U2.55 / SC 0.59-5-226912151821242729DG / U2.79 / SC 0.61

-11-7-3158111518212326DG / U3.2 / SC 0.7495%90%85%80%75%70%65%60%55%50%45%40%Window / FWR

Perc

ent e

nerg

y re

duct

ion

from

MN

ECB

Expansion of FWR doesn’t compromise benefits of other strategies

Fenestration + 3 measures exceeds LEED™ Ca-NC EAp2

Expansion of FWR compromises benefits of other strategiesFWR & SC w/ MNECB Reference values fail to satisfy LEED Ca-NC EAp2

Expansion of FWR allows some flexibility with trade-offs

Toronto Small Office archetype

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High Performance Office FWR

444647495051525354565657TG / U0.94 / SC 0.31424445474849505253545556TG / U1.10 / SC 0.46 404143454647495051525455TG / U1.30 / SC 0.50353840414345474850515253DG / U1.62 / SC 0.41353739414244464849505253DG / U1.68 / SC 0.41333537394143454648495152DG / U1.82 / SC 0.56323537394142444647495052DG / U1.89 / SC 0.56252830333537394143454748DG / U2.45 / SC 0.59242629323436394143444648DG / U2.55 / SC 0.59202326293234363941434546DG / U2.79 / SC 0.61161923252831333638404244DG / U3.2 / SC 0.74

95%90%85%80%75%70%65%60%55%50%45%40%Window / FWR

Perc

ent e

nerg

y re

duct

ion

from

MN

ECB

Expansion of FWR allows flexibility with trade-offsExpansion of FWR doesn’t compromise benefits of other strategies

Fenestration + 8 measures delivers 2030 Challenge target for 2008-2010

Expansion of FWR compromises benefits of other strategiesFWR & SC w/ MNECB Reference values fail to satisfy LEED Ca-NC EAp2Toronto Small Office archetype

8 Cities on 1 Chart

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8 Cities Comparison

Investigation of relative energy patterns for a common building archetype;

Does the type behave the same way in all climate zones?

How much improvement can be expected from envelope improvements?What impacts can be attributed to climate alone?

Impact of general construction practice –reference building values;Impact of differences in solar conditions.

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8 Cities: Walls

2,4002,6002,8003,0003,2003,4003,6003,8004,0004,2004,400

1 1.5 2 2.5 3 3.5 4 4.5 5 5.5 6 6.5 7 7.5

Wall RSI

Ener

gy C

onsu

mpt

ion

GJ

Calgary Regina Toronto Whitehorse WinnipegHalifax Montreal Vancouver

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Whitehorse vs. Regina

WhitehorseHeating Degree Days:

6,900Reference Values:Walls: RSI = 2.7Roofs: RSI = 3.5Windows: USI = 2.1

ReginaHeating Degree Days:

5,750Reference Values:Walls: RSI = 2.1Roofs: RSI = 2.5Windows: USI = 3.2

.…A little bit goes a long way….

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8 Cities: Roofs

2,400

2,600

2,800

3,000

3,200

3,400

3,600

3,800

4,000

4,200

4,400

2 2.5 3 3.5 4 4.5 5 5.5 6 6.5 7 7.5

Roof RSI

Ener

gy C

onsu

mpt

ion

GJ

Calgary Regina Toronto Whitehorse WinnipegHalifax Montreal Vancouver

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8 Cities: Window Area

2,500

3,000

3,500

4,000

4,500

5,000

5,500

6,000

6,500

7,000

40 45 50 55 60 65 70 75 80 85 90 95

Fenestration-to-wall ratio %

Ener

gy C

onsu

mpt

ion

GJ

Calgary Regina Toronto Whitehorse WinnipegHalifax Montreal Vancouver

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8 Cities: Window Performance Values

2,2002,4002,6002,8003,0003,2003,4003,6003,8004,0004,2004,400

0.75 1 1.25 1.5 1.75 2 2.25 2.5 2.75 3 3.25

Window U Value

Ener

gy C

onsu

mpt

ion

GJ

Calgary Regina Toronto Whitehorse WinnipegHalifax Montreal Vancouver

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Some observations from 8 Cities:

Ranking of energy consumption by city stays stable;Relative performance of energy efficiency measure by city stays stable;Selection of Reference Building (Prescriptive) performance values is significant;Controlling FWR is the easiest way to control envelope performance;Super-insulation for even relatively small commercial buildings is not a “silver bullet” for energy efficiency:

“Good practice” residential resistance values approach the optimum.

41

Thank You

Stephen Pope, OAA, FRAICSustainable Building Design Specialist

Natural Resources Canada / CanmetENERGYSustainable Buildings & Communities / Commercial Buildings Section

580 Booth St., 13th Flr, D5, Ottawa ON K1A 0E4tel. (613) 947-9823 cell (613) 324-1642, fax (613) 996-9909

email - spope@nrcan.gc.ca, web - http://www.sbc.nrcan.gc.ca