2. Heat Transfer is quantified in British Thermal Units (BTU s)

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2 Basic Concepts 2. Heat Transfer is quantified in British Thermal Units (BTU s) 1 Btu is approximately equal to the energy in a single match. 3 INNOVATION & INTEGRATION: Transforming the Energy Efficiency Market Buildings.Energy.gov

3 Thermal Holes Are a Big Deal 1, 000 sq. ft. R-38 Attic U =.026 Drop-Down Stair = R-1 R-1, U = sq. ft. = 1% of area What Percent Loss in Attic R-Value? 4 INNOVATION & INTEGRATION: Transforming the Energy Efficiency Market Buildings.Energy.gov

4 Thermal Holes Are a Big Deal Avg. U = = = U1 x A1 + U2 x A2 + Total Area (A) (.026 x 990) + (1 x 10) 1, ,000 =.036 R-28 27% < R-38 = = 1% Hole Results in 27% Loss of R-Value 5 INNOVATION & INTEGRATION: Transforming the Energy Efficiency Market Buildings.Energy.gov

5 Thermal Holes Are a Big Deal Assume 50 o F temperature difference across attic ceiling Heat Flow = U x A x T Heat Flow w/o Hole =.026 X 1,000 x 50 = 1316 Btu/hr Heat Flow w/hole =.036 x 1,000 x 50 = 1786 Btu/hr 33%+ Greater Heat Flow with 1% Hole 6 INNOVATION & INTEGRATION: Transforming the Energy Efficiency Market Buildings.Energy.gov

6 The Biggest Thermal Hole. 8 INNOVATION & INTEGRATION: Transforming the Energy Efficiency Market Buildings.Energy.gov

7 Yes Windows Are a Big Deal Window 15% of Wall Area Wall R-Value with Windows w/varied Wall Insulation Levels U-Value R-0 R-18 R-39 R R-5 R-11 R-15 R R-5 R-13 R-19 R R-5 R-14.5 R-23 R R-5.5 R-16 R-27 R-34 Sources: Holes in the Wall: To Improve the Energy Performance of Walls, Look at the Total R-Value, Journal of Light Construction, February 2014; Multi-Assembly R-Value / U-Value Calculator Cascadia Windows and Doors; Michael Blasnik Presentation, 2014 ACI Conference 9 INNOVATION & INTEGRATION: Transforming the Energy Efficiency Market Buildings.Energy.gov

8 Thermal Defects Are More Obvious 10 INNOVATION & INTEGRATION: Transforming the Energy Efficiency Market Buildings.Energy.gov

9 Thermal Defects Are More Obvious 11 INNOVATION & INTEGRATION: Transforming the Energy Efficiency Market Buildings.Energy.gov

10 Optimized Enclosure System Air-Tight Construction Complete Air Barriers - Thermal Bypass - Wind Intrusion Insulation System - Next Code Quantity - Proper Installation - Minimum Thermal Bridging Advanced Windows Air and Thermal Flow Control 12 INNOVATION & INTEGRATION: Transforming the Energy Efficiency Market Buildings.Energy.gov

11 Zero Energy Ready Home Zero Specifications Optimized Enclosure System Air-Tight Construction 13 INNOVATION & INTEGRATION: Transforming the Energy Efficiency Market Buildings.Energy.gov

12 Why Air-Tight Construction 16 to 50% of HVAC Loads Moisture Problems Comfort Problems Indoor Air Quality 14 INNOVATION & INTEGRATION: Transforming the Energy Efficiency Market Buildings.Energy.gov 14

13 Target Home Air-Tightness ACH50 Requirements/Targets Climate Zones Zero Energy Ready Home ENERGY STAR V IECC Passive House INNOVATION & INTEGRATION: Transforming the Energy Efficiency Market Buildings.Energy.gov

14 Seal Usual Suspects Penetrations: Plumbing Wiring Recessed Lights Vents HVAC Duct Boots Shafts: Flues Ducts Plumbing Cracks: Sill Plates Windows & Doors Drywall at Top Plate Access Panels Sheathing Joints Foundation/Framing Odd Geometry: Cantilevers Knee-walls 17 INNOVATION & INTEGRATION: Transforming the Energy Efficiency Market Buildings.Energy.gov

15 What We re Trying to Avoid Attic air infiltration into the wall 18 INNOVATION & INTEGRATION: Transforming the Energy Efficiency Market Buildings.Energy.gov

16 Drywall Sealed at Top Plates Default: Spray Foam Alternative: Sill sealer Alternative: Constr. Adhesive 19 INNOVATION & INTEGRATION: Transforming the Energy Efficiency Market Buildings.Energy.gov

17 Air Leakage Distribution Exterior air barrier Cathedral ceiling 6% 1% Sheathing / roof joint Pa 93% Sheathing / top plates Stud / top plates Top plates Zones 2-Story house (Floor area = 2,000 ft 2 ) Sheathing / roof joint unsealed 0.5 ACH 50 DOE Zero Energy Ready Home Requirement Contribution to requirement (%) Requirement IECC 2012 Contribution to requirement (%) INNOVATION & INTEGRATION: Transforming the Energy Efficiency Market Buildings.Energy.gov

18 Rectangular Electrical Box - 1/8 to 1/4 perimeter gap - ~ Pa - Perimeter gap sealed - Somewhat effectively with one-component polyurethane foam - Effectively with caulk - Wire holes 50% of leakage 23 INNOVATION & INTEGRATION: Transforming the Energy Efficiency Market Buildings.Energy.gov

19 Fasteners Air leaked at nailed fasteners Repeat test with screwed fasteners 25 INNOVATION & INTEGRATION: Transforming the Energy Efficiency Market Buildings.Energy.gov

20 Air Leakage Contribution Estimates Exterior Air Barrier: 2-Story House (2,000 sq. ft.) (4) Elect. Outlets = 0.17 ACH 50 Exterior Sheathing/Foundation = 0.51 ACH 50 (5) Lights = 0.29 ACH 50 Ext. Sheathing/Roof = 0.51 ACH 50 Air barrier Duct 0.22 ACH Sheathing/Foundation Joint Unsealed = Sheathing/Roof Joint Unsealed = (4) Electrical Outlets = (5) Ceiling Lights = Return Duct = ACH INNOVATION & INTEGRATION: Transforming the Energy Efficiency Market Buildings.Energy.gov

21 Sealing HVAC Ducts with Aeroseal 27 INNOVATION & INTEGRATION: Transforming the Energy Efficiency Market Buildings.Energy.gov

22 Air Sealing Homes with Aerosol Photos from wcec.ucdavis.edu 28 INNOVATION & INTEGRATION: Transforming the Energy Efficiency Market Buildings.Energy.gov

23 Zero Energy Ready Home Zero Specifications Optimum Enclosure System Complete Air Barriers 29 INNOVATION & INTEGRATION: Transforming the Energy Efficiency Market Buildings.Energy.gov

24 Complete Air Barriers Walls Showers and Tubs Fireplaces Attic Knee Walls Skylight Shaft Walls Adjoining Porch Roof Staircase Exterior Walls Double Walls Rim/Band Joists Other Exterior Walls Floors Floors Above Garage Cantilevered Floor Unconditioned Floor (Basement/ Crawl Space) Ceilings Dropped Ceiling/ Soffit at Unconditioned Attic Other Ceilings 30 INNOVATION & INTEGRATION: Transforming the Energy Efficiency Market Buildings.Energy.gov 30

25 Complete Air Barriers 31 INNOVATION & INTEGRATION: Transforming the Energy Efficiency Market Buildings.Energy.gov

26 Air Barrier Example: Attic Knee Wall No rigid backing on knee wall. Rigid backing installed prior to insulation. 32 INNOVATION & INTEGRATION: Transforming the Energy Efficiency Market Buildings.Energy.gov

27 Air Barrier Example: Garage Rim Joist No air barrier is present between garage and conditioned space. Air barrier is present between garage and conditioned space. 33 INNOVATION & INTEGRATION: Transforming the Energy Efficiency Market Buildings.Energy.gov

28 Air Barrier Example: Wall Adjoining Porch Roof No air barrier between porch attic and conditioned space. Air barrier is installed prior to porch attic framing. 34 INNOVATION & INTEGRATION: Transforming the Energy Efficiency Market Buildings.Energy.gov

29 Zero Energy Ready Home Zero Specifications Optimized Enclosure System Insulation System 35 INNOVATION & INTEGRATION: Transforming the Energy Efficiency Market Buildings.Energy.gov

30 2012 IECC Insulation Compliance with next generation code Three Options: Prescriptive Alternative equivalent U-factor Total UA calculation [allows window to be included] Allowances for ceilings without attic spaces [up to 500 square feet or 20% of roof area, whichever is smaller] 47 INNOVATION & INTEGRATION: Transforming the Energy Efficiency Market Buildings.Energy.gov

31 Insulation Proper Installation Gap Void Compression Misalignment 52 INNOVATION & INTEGRATION: Transforming the Energy Efficiency Market Buildings.Energy.gov