Deep Green Retrofits. Rob Dumont Dumont and Associates

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Elinor Mills
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1 Deep Green Retrofits Rob Dumont Dumont and Associates

2 Why Deep Green? 1. We currently have a climate crisis. Climate scientists are calling for a reduction in carbon emissions of at least 2 times from current levels. 2. World population is expected to increase by a factor of 1.5 by Because there are so many people in poor countries, it is expected that average consumption per person in the world will increase by a factor of 3 before stabilizing.

3 Multiply these three factors together: 2 x 1.5 x 3 = 9 In other words, with that amount of growth in people and consumption, and the need to reduce carbon emissions, the only way to address the problem is reduce the carbon emissions of all buildings, transportation, industry and agriculture by a factor of 9.

4 What would sustainable buildings look like?

5 Discovery 3 Home in Red Deer, Alberta One of Canada s EQuilibrium Homes Projected Net Zero Energy on an annual basis Energy Conservation Features: R87 Roof, R70 Walls, R60 Floor, R5 Windows, air tightness goal of pascals, Heat Recovery Ventilator Energy Supply: Passive solar, Active solar, 8.3 kilowatt PV system

6 Annual Purchased Energy Consumption (kwh/sq.m.) Effect of Conservation and Renewable Energy Measures Base Case Hse 1. Reduce Space Heat 2. Reduce Water Heat 3. Reduce Lights and Appliances 4. Space Cooling 5. Install Solar Water Heat 6. Install Photovoltaics Conservation and Renewable Energy Measures

7 Observations 1. Space Heating Load is the greatest single load 2. Water Heating Load is the second greatest load 3. LAME (Lights, Appliances and Misc) is the third greatest load Reducing these three has the greatest impact on the house performance

8 Comparison of Inuvik and Red Deer Climates Inuvik Red Deer Annual Heating Degree Days (C-days) Outdoor Design Temp for heating systems Annual Solar Radiation on a horizontal Surface (GJ/m2) 10, C C

9 Comparison of Inuvik and Red Deer Climates Inuvik Red Deer Latitude Angle (degrees) Annual Solar Radiation on a South Facing Surface tilted at the latitude angle (Gigajoules/m 2 )

10 Classic Analysis of Optimum Amount of Insulation Optimum amount of insulation is that amount which minimizes the combined cost of the installed insulation and the cost of the fuel to heat the space Consider only the cost of insulation and cost of fuel

12 Cost of Batt Insulation In southern Canada Approximately 3 cents per square foot per R value Thus R100 in a 1000 square foot attic would cost about $3000

13 Cost of Rigid Insulation

14 Cost of Rigid Insulation In southern Canada Approximately 15 cents per square foot per R value Thus R100 in a 1000 square foot attic would cost about $15000

15 Optimum R value = Square root( Cost of fuel x annual heating degree days x present worth factor x internal heat gain factor / cost of insulation) (This approach was used in the development of the Model National Energy Code for Houses for Canada)

16 Optimum R values for Inuvik Heating Degree Days Cost of Fuel Can. $/litre Cost of Insulation $/ft2 per R value Optimum R value English Units H-ft2-F/BTU

17 Recommended Revised Analysis of Optimum Insulation Levels Optimum amount of insulation is that amount which minimizes the combined cost of the installed insulation and the cost of the fuel to heat the space PLUS the cost of the heating system. PLUS the cost of the environmental damage (Estimated at $200 per tonne of CO 2 )

18 What does a heating system cost for a modest house install? Cheap: Electric baseboards ($1k -$2k) Cheap: Point source heating ($2k-$5k) Intermediate: Forced air with fossil fuel ($10k- 15k) High: Boiler system with fossil fuel ($15k - $30k)

19 Example of a Point Source Oil Fired Space Heater Toyotomi Space Heater 22,000 BTU/hr (6.4 kilowatts) 90% Efficient AFUE $2600 Cdn including Thru-wall vent kit

20 Comparison of Capital Costs of Insulation plus Heating Standard Code House with Boiler System Insulation $5,000 Heating System $20,000 $25,000 Superinsulated House with Point Source Heating Insulation $15,000 Heating System $5,000 $20,000

21 Observation: Consider the total cost of the thermal comfort system including the heating system, and not just the cost of the insulation Use an integrated design Talk to Juergen Korn of Yukon Housing

22 Techniques for Superinsulated Retrofits Source Books: The Super-insulated Retrofit Book by Robert Argue (1982, Firefly Books, available from Keeping the Heat In by Natural Resources Canada

23 Case Study Double-Wall Double Roof Retrofit Location: Saskatoon Annual Heating Degree Days: 5950 HDD Celsius 1968 Bungalow

25 Pre-Retrofit

26 Post Retrofit

27 Pre-Retrofit

28 Comparison of Pre and Post Attic Insulation Wall Insulation (Nominal) Bsmt Floor Insulation Pre-Retrofit R20 RSI 3.5 R 7 RSI 1.2 Post- Retrofit R60 RSI 10.7 R 47 RSI 8.3 R 0 No change ; Later R20 was added in another expt. Ratio Post/Pre Windows R2 R3 1.5 Air Tightness 2.95 Pa 0.29 Pa 0.10

29 Energy Results Peak Heat Loss reduced from 13.1 kw to 5.5 kw

30 Step 1. Cut off eaves and wrap roof and walls with poly (sometimes called the chainsaw retrofit )

31 Step 2. Add second roof

32 Step 3. Add exterior wall system

33 Step 4. Finish details around windows & doors

34 Insulation of walls & bsmt walls

35 R40 on Roof ; R40 on Walls; R40 in Bsmt Walls

36 Post Retrofit Asphalt Shingles, Stucco Walls

37 February 2010 View of House

39 Comparison of Pre and Post Attic Insulation Wall Insulation (Nominal) Bsmt Floor Insulation Pre-Retrofit R20 RSI 3.5 R 7 RSI 1.2 Post- Retrofit R63 RSI 12.5 R 47 RSI 8.3 R 0 No change ; Later R20 was added Ratio Post/Pre Windows R2 R3 1.5 Air Tightness 2.95 Pa 0.29 Pa 0.10

41 The Super Insulated Retrofit Book by Robert Argue & Brian Marshall

42 Saskatchewan Examples of Deep Green Retrofits

43 Before: 1950s Wood Frame building with concrete block foundation walls

44 Double wall, double roof retrofit 1950s 4 Plex in Regina, Saskatchewan Harold Orr was designer of the retrofit Achieved an 82% reduction in air leakage Achieved an 85% reduction in space heating Former single forced air furnace with one thermostat for 4 suites was replaced by thermostatically controlled point source natural gas fireplaces (1 per suite)

45 Post-Retrofit

46 Use of point source heating (fireplace) in each of the 4 suites.

47 New primary heating system consisted of 4 fireplaces Cost of new primary heating system: 4 fireplaces x $2500 = $10,000 Back bedrooms also each had one 500 watt electric baseboard heater (rarely used, as the tenant pays for electricity, while the landlord pays for natural gas)

48 Further information on the entire sequence of the retrofit /Harold%20Orr.ppt

49 Roof retrofit

50 Roof Retrofit

51 First Double Wall Retrofit- 1978, Saskatoon House

52 Small House Retro 1988 Double Wall Retrofit

53 Shed Roof on back of House was Double-Roofed to address Condensation Problem Custom Solar Builders, Saskatoon, did the work

54 Advantages of Double Wall/Double Roof Retrofits 1. Conduction losses can be greatly reduced 2. Air leakage can be greatly reduced 3. Heating system can be greatly simplified in many cases because of the reduced heat loss. (e.g. Fireplace is sufficient to heat a modest space.) 4. Provides opportunity to address simultaneous need for upgraded roofing and siding. 5. Space on the interior is not lost. 6. House can be occupied while work is in progress

55 Summary 1. Because of global warming concerns, deep retrofits are needed for our existing housing stock. 2. Deep green double wall, double roof retrofits have a track record of proven performance dating back up to 30 years. 3. Optimum insulation levels depend on more than just the cost of fuel and the cost of insulation. Consider also the capital cost of the heating system 4.Let s get on with it.

56 Acknowledgements: Staff of the Institute for Research in Construction of the National Research Council of Canada Harold Orr, who conceived the retrofit strategy and guided its development Private contractors, including Rod Gibson of Custom Solar Builders, Saskatoon

Case Study #9 Phoenix Rising

Case Study #9 Phoenix Rising SUMMARY: This profile features the first of Habitat for Humanity s (HFH) SuperGreen houses built in the Yukon. They began constructing this triplex after Yukon Housing Corporation