SB-12, Chapter 3. Applicable to all building permit applications submitted after December 23, 2016

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1 Updated: July 7, 2016 Effective: January 1, 2017 Applicable to all building permit applications submitted after December 23, 2016 Building permit applications submitted before December 24, 2016 are regulated by Chapter 2 of SB-12, however construction must commence within 6 months after the permit is issued. Publications of the updated SB-12 are available here. Disclaimer: The information and calculations provided here within are not guaranteed to be correct. Reference should always be made to the Building Code and Supplementary Standards, as amended, for information on the construction and use of buildings. Reference should also be made to all other applicable reference documents and guidelines. This publication should not be relied upon as a substitute for legal or design advice.

2 1 Administrative» The July 7, 2016 update contained with Chapter 3 of SB-12 includes acceptable solutions for achieving energy efficiency compliance with Clause (3)(b) of Division B of the Building Code.» Conformance with one of the new prescriptive compliance packages, the performance compliance method, or the Energy Star or R2000 requirements is intended to achieve an energy efficiency performance level that exceeds the current energy efficiency requirements of Chapter 2 by 15%.» In addition to revising the compliance packages, changes also include the identification of credits based on airtightness, and the recognition of Energy Star and R2000 programs as design options for meeting the energy efficiency requirements of the Building Code.

3 2 Objectives» Preserve and reinforce investment in the building envelope» Encourage air tightness and associated blower door testing» Prepare the industry for movement towards Net-Zero like housing by 2030

4 3 Key Changes» Fewer prescriptive compliance packages» Different prescriptive compliance packages depending on space heating equipment efficiency ( A for 92%, B for 84% to < 92%)» Emphasis on thermal bridging (continuous insulation, such as rigid, blanket or spray-foam, required in most packages)» Effective R-values added as an option» HRV or ERV required in all prescriptive homes» Drain water heat recovery required in most prescriptive homes

5 4 Options for compliance» Subsection (prescriptive compliance)» Subsection (performance compliance)» Subsection (other acceptable methods) Energy Star R2000 (new)

6 5 Prescriptive Compliance Table A (AFUE 92%)

7 6 Prescriptive Compliance - Comparison Component OBC 2012: Package J OBC 2017: Package A1 Attic R50 (8.81 RSI) R60 (10.56 RSI) Cathedral R31 (5.46 RSI) R31 (5.46 RSI) Floor R31 (5.46 RSI) R31 (5.46 RSI) Walls R22 (3.87 RSI) R22 (3.87 RSI) Basement R12 (2.11 RSI) R20 CI (3.52 RSI CI) Windows 1.8 U-Value (ER 21) 1.6 U-Value (ER 25) Space heating 94% 96% HRV 60% 75% Water heater 0.67 EF 0.80 EF Drain water Not required 42% Estimated energy consumption GJ GJ

8 7 Prescriptive Compliance air tightness trade-offs» Air tightness targets: 2.5 ACH (detached), 3.0 ACH (attached)» If air tightness credit is claimed, it shall be verified by air leakage testing (Note: Recommended early, such as at air barrier (pre-drywall) stage)» Table B for one substitution, or Table C for two substitutions» Examples include reducing furnace efficiency by 4%, increasing window U-value by 0.2, reducing insulation values What if air tightness is claimed, but cannot be verified?

9 8 Prescriptive Compliance effective R-values» Focus on using effective R-values instead of nominal R-values to provide added design flexibility» Effective R-values are the total resistance provided by all components in an assembly (e.g.: drywall, insulation, framing, cladding, etc.)» When choosing effective R-values, calculations are required to be submitted prior to permit issuance» Design criteria for effective calculations prescribed in footnotes to compliance packages table Effective R-value calculator available from Natural Resources Canada Thermal wall design calculator available from the Canadian Wood Council

10 9 Prescriptive Compliance effective R-values, samples Wall assembly (includes drywall & air spaces) Nominal R-value Effective R-value 2 x6 16 o.c., R22 cavity, OSB, siding R 22 R x6 24 o.c., R24 cavity, OSB, siding R 24 R x6 16 o.c., R20 cavity, R5 CI, siding R 25 R x6 16 o.c., R20 cavity, R5 CI, brick R 25 R x4 16 o.c., R14 cavity, R7.5 CI, siding R 21.5 R x4 24 o.c., R14 cavity, R10 CI, siding R 24 R x6 24 o.c., R22 cavity, R10 CI, siding R 32 R 27.0

11 10 Prescriptive Compliance effective R-values, sample calculations (R21.12) * Where the basement is finished or drywall installed, drywall and other components that contribute to effective RSI value will be added. Effective 2.81 (R21.40) * Where exterior finish is brick, brick and air gap values are permitted to be substituted for siding. 2 x6 24 o.c. c/w RSI 3.52 (R20) 2.81 (R17.09) 3.01

12 11 Prescriptive Compliance effective R-values, sample calculations (R49.23) (R29.80)

13 12 Windows» Highest permitted U-value in prescriptive compliance packages is now 1.6 W/(m²K)» Energy ratings still permitted to be used in lieu of U-values, however not recommended (Note: Basing window selection on U-values & SHGC results in a more balanced performance level during heating and cooling seasons)» Air tightness trade-offs for U-value increase of 0.2 W/(m²K)» Specialty glazing products totaling up to 1.85m² need not comply with thermal performance requirements [Sentence (4)] (Note: Shall still be included in wall/glazing ratio calculation)

14 13 Windows» The average U-value of all windows is permitted to be used [Sentence (5)] (Note: When the average is being used, calculations shall be provided prior to issuance of building permit) Example: Compliance package requires a U-value of 1.6 Average U-value 16.8 / 11.0 = 1.52 Compliance achieved! Window U-value Area (m²) U-value x Area Living room Dining room Master bedroom Bedroom Bathroom Total

15 14 Doors» Sentence (9) is not included in Chapter 3, therefore glazing in main entrance doors and adjacent sidelights shall be included in glazing/wall ratio calculation» One exterior door system is exempt from thermal performance requirements (e.g.: wood door systems) [Sentence (2)]» All doors separating heated space from unheated space shall be insulated and weather-stripped [Sentence (3)] (Note: Although Sentence (1) exempts cold cellar doors from having a thermal resistance of R4 (RSI 0.7), sentence (3) requires all doors separating heated and unheated space to have an insulated core)

16 HRV / ERV» Now required in all prescriptive packages» Minimum efficiency increased from 55% to 65% (Note: Efficiency is the "Sensible Recovery Efficiency (SRE)" listed at a temperature of 0 degrees celcius and at the principle exhaust flow rate, but not exceeding 30 L/s) Water heaters» Minimum efficiency increased to 0.67 (Refer to Energy Star website to confirm compliance with various models) Drain water heat recovery» Required in all prescriptive packages with at least one shower that has a floor level or crawl space below (e.g.: access provided)» Minimum 42% efficiency 15

17 16 Performance Compliance» Shall conform to Subsection » Specific energy use software required» Requires simulated energy use calculations to compare the annual energy use of the proposed building with that of a comparable compliance package» Simulated annual energy use of the proposed building cannot exceed the simulated annual energy use of the comparable compliance package

18 17 Other Compliance Methods EnergyStar» NRCan, Energy Star for New Homes Standard, Version 12.6» Energy Evaluator required» Certificate required to demonstrate compliance R2000» NRCan, 2012 R-2000 Standard» Energy Evaluator required» Certificate required to demonstrate compliance

19 18 Energy Efficiency Design Summary Prescriptive Compliance

20 19 Energy Efficiency Design Summary Performance Compliance 1 of 2

21 20 Energy Efficiency Design Summary Performance Compliance 2 of 2

22 City of Guelph Building Services