1 / 14

Energy Efficiency in Housing and Small Buildings Building Envelope

Energy Efficiency in Housing and Small Buildings Building Envelope. Pre-Public Review December 2011. Building Envelope. Outline Structure of the Subsection Insulation Requirements Nominal vs Effective NECB – Part 9 Comparison Preliminary results from validation

candid
Download Presentation

Energy Efficiency in Housing and Small Buildings Building Envelope

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Energy Efficiency in Housing and Small BuildingsBuilding Envelope Pre-Public Review December 2011

  2. Building Envelope • Outline • Structure of the Subsection • Insulation Requirements • Nominal vs Effective • NECB – Part 9 Comparison • Preliminary results from validation • Revised Tables for insulation requirements • Airtightness requirements • Simple Trade-Off

  3. Structure of the Subsection • 9.36.2. Building Envelope • 9.36.2.1. Scope and Application • 9.36.2.2. Determination of Thermal Characteristics & Areas • 9.36.2.3. Determination of Areas of Wall and Fenestration • 9.36.2.4. Calculation of Thermal Resistance for Assemblies • 9.36.2.5. Continuity of Insulation • 9.36.2.6. Above Ground Assemblies • 9.36.2.7. Windows, Doors and Skylights • 9.36.2.8. Below Ground Assemblies • 9.36.2.9. Required Level of Airtightness • 9.36.2.10. Construction of Air Barrier Details • 9.36.2.11. Simple Trade-offs for Building Envelope

  4. Scope & Application • Scope & Application • heat transfer and air leakage • between conditioned space and unconditioned space, the exterior air or the ground • between conditioned space and an adjoining storage garage, even if the storage garage is intended to be heated • How to test materials and components for their R-values • How to calculate areas of walls, and fenestration • Calculation of effective thermal resistanceof assemblies

  5. Required Thermal Characteristics • Opaque Assemblies • Above Ground: walls, attics, floors over unheated spaces, etc. • Below Ground: foundation walls, floor slabs, heated slabs etc. • minimum effective thermal resistance (RSI = 1/U) • 2 Compliance Paths • R-values based on mechanical ventilation (no HRV) @ 2.5 ACH • R-values based on HRV @ 2.5 ACH • Windows Doors & Skylights • Manufactured fenestration components: • Maximum overall thermal transmittance (U = 1/RSI), or • Minimum Energy Rating (ER) values (not for skylights) • Prescriptive specifications for site-built windows

  6. Code Requires Effective RSI Values • Example: 2 x 6 construction - 16” on center • Code: Required Minimum Effective Value: RSI 2.93 (R16.6) • Appendix: Nominal Insulation Examples: RSI 3.34 (R19) R6.9 R19 framing 23% 77% cavity

  7. Look-up Nominal Values • Above Grade Requirements • Appendix – Lookup Tables

  8. Nominal Values (Appendix) • Above Grade Requirements • Appendix – Lookup Tables

  9. Nominal Values (Appendix) • Above Grade Requirements • Appendix – Lookup Tables

  10. Calculation of RSI Values • Above Grade Assemblies – Requirements (Example) • Appendix – Calculation • Formula • Methods (isothermal/parallel) • Framing Percentages (wood/metal) • Material Values (MNECH97,IRC,ASHRAE) • Log Walls (MNECH97) framing 23% 77% cavity

  11. Windows, Doors and Skylights • Energy Star criteria 2010 • No defined term for “fenestration” • Exemptions • Storm doors exempt • 1 front door and attic/crawl space hatches U = 2.6 W/m²K • Garage door RSI = 1.1 m²K/W

  12. Airtightness • Prescriptive construction details • Different approaches (poly, ADA, exterior sheathing) • Typical penetration and junctions • Testing for Assemblies • ULC S742 Air Barrier Assemblies • Provide junction details (mfg’s instructions) • Blower Door Test • Optional: Required Performance 2.5 ACH • Subject to policy discussion with CCBFC • Mandatory where 1.5 ACH are required

  13. Airtightness • Prescriptive compliance path • General Requirements • Compliance, exemptions, cross references • Construction Details • Material values, continuity, sealants • Electrical Outlets and Switches • Sill Plates • Window-Wall Interface • Overhangs • Party Wall details • Chimney’s and duct’s penetration • ICF (top of the wall to attic ceiling)

  14. Simple Trade Off • Formula • Options: • Opaque to Opaque • Opaque to Transparent (areas remain the same) • Trade Areas • Applies only to • houses/bldgs with FDWR 15% or less • Max, ce-ling height 7’ 8” • Limitations • Can’t reduce below 55% of the R-value for walls and attic roofs • Can’t reduce below 60% of the R-values of other opaque assemblies • Does not apply to heated assemblies • Does not apply to components and assemblies already exempted

More Related