THE FACTOR 9 HOME: A NEW PRAIRIE APPROACH

1 2 3 4 5 6 7 8 9 10 ABSTRACT THE FACTOR 9 HOME: A NEW PRAIRIE APPROACH Robert Dumont and Tara Morin Building Performance Business Unit, Saskatchewan Research Council 15 Innovation Boulevard, Saskatoon, SK, S7N 2X8 dumont@src.sk.ca The Factor 9 Home: A New Prairie Approach is a demonstration project of a single family residence located in Regina, Saskatchewan, Canada, that features very high levels of energy efficiency and environmental performance. The home was completed in April 2007. The Factor 9 Home is projected to use a factor of 9 times less energy per square metre of floor area than the average existing home in Saskatchewan. The resulting energy target is 30 kwh/m 2 per year (108 megajoules/ m 2 -year) of total purchased energy consumption. Another numerical performance target for the home is a Factor 2 reduction in purchased water consumption from the utility compared with conventional homes. The major technical approaches used to develop the Factor 9 Home were Integrated Design and Value Engineering. This paper presents information on the features of the house and the monitoring strategy. INTRODUCTION The name Factor 9 for the project was developed for the following reasons. World population is expected to increase from current levels by about a factor of 1.5 before stabilizing. Material consumption per average person in the world is expected to increase by a factor of about 3 from current levels before stabilizing. Climate scientists have called for a reduction of current greenhouse gas emissions by about a factor of at least 2 from current levels. If these three factors are multiplied together, the number 9 results. Hence the Factor 9 energy target for this demonstration house was developed. The lot was chosen so as to have the rear of the house face south for passive and active solar gain. The lot address is 7335 Wascana Cove Place in Regina, Saskatchewan. The subdivision chosen is a new area in the city that has access to public transport. The topography is very level. To reduce water runoff from the roof, rainwater and melted snow water from the roof will be stored in two 9500 litre storage tanks in the crawl space beneath the basement floor. This nonpotable water will be used for toilets and exterior water usage. Landscaping is being designed to reduce the need for water. HOW ENERGY CONSUMPTION WILL BE REDUCED The house will feature a very energy conserving envelope, with attic insulation levels of RSI 14.1 (R80), above grade walls of RSI 6.2 (R35), basement wall insulation levels of RSI 6.7 (R38.5) and basement floor insulation of RSI 2.1 (R12). The building will be very well sealed, with an air tightness goal of 0.5 air changes per hour at 50 pascals, three times tighter than the R-2000 standard of 1.5 ac/h at 50 Pa. Passive solar heating will be used to provide space heating (passive is projected to provide 41% of the total annual space heating requirement). Active solar heating will be used with 20.4 square meters of double glazed vertical solar panels mounted on the south wall of the house. The south wall faces 26 degrees east of due south. A 2350 litre water storage tank in the basement is used to store the heat from the solar panels. To distribute the space heating for the house, a fan coil with brushless direct current motors is used. The active solar panels will also be used to provide domestic water heating. A passive waste water heat exchanger is used to preheat the domestic hot water prior to the solar storage tank. To provide mechanical cooling in the summer, a network of plastic pipes has been installed in the 22 concrete pilings to extract cooling from the ground. The approximate annual ground temperature at the base of the pilings is about +5 C. The water in the plastic

pipes will provide space cooling for the house. The same fan coil used for space heating will also be used for space cooling. Energy efficient lights and appliances will also be used. FOUNDATION Regina has active clay soils that shrink and swell greatly under varying moisture conditions. To limit movement of the house and greatly improve its durability, 22 concrete pilings 4.6 metres deep have been used for the foundation. A concrete grade beam sits on the pilings. A photo of the basement excavation is shown in Figure 1. Figure 3. Levelling of the piling caps. The orange plastic pipe is visible at the top of each pile. A total of two loops of plastic pipe were placed in each of the piles to extract cooling. A concrete grade beam was placed on top of the pilings, and a wood truss floor used for the basement floor. A picture of the wood floor is shown in Figure 4. Figure 1. Basement excavation and drilling of the piles for the home. May 2006 Placement of the cooling pipes in the piling holes. Figure 2 shows the steel rebar along with the plastic cooling pipes. Figure 2. Rebar and plastic cooling pipes for the pilings A photo of the tops of the concrete pilings is shown in Figure 3. Figure 4. View of the basement floor with wood trusses. Some of the basement walls have been put in place. A generous crawl space is placed beneath the basement floor. Two membrane tanks have been placed in the crawl space for storage of water collected from the roof. ENVELOPE The basement walls are structural insulated panels with polyurethane foam between the inner skin of oriented strand board and the outer skin of pressure treated plywood.

A picture of the basement walls being assembled is shown in Figure 5. Figure 7. View of the house from the south. The blue material on the basement walls is a peel and stick waterproofing membrane. Granular material was used as backfill for the basement walls to help avoid soil pressure loads from the expanding clay soil. High heel roof trusses were used to help accommodate the high attic insulation levels. Figure 5. View of the concrete grade beam and the structural insulated panels for the basement walls. The canvas straps are used to pull together the panels. A cross section of the construction of the walls of the house is shown in Figure 8. Another view of the basement walls and floor is shown in Figure 6. Figure 6. Basement walls and floor for the house. The window opening in the foreground is on the south side of the house. Structural insulated panels were also used for the main floor of the house. A view of the main floor walls is shown in Figure 7. Figure 8. Cross section of the wall construction for the house. The basement walls use structural insulated panels. The middle rim joist area uses an insulated rim board. The upper walls are also structural insulated panels. The exterior of the house is clad with an insulating brick product.

A view of the house near the completion of the framing stage is shown in Figure 9. Upgraded asphalt shingles were used on the roof. A picture is shown in Figure 11. Figure 11. View from the North of the house. Asphalt shingles have been installed, along with the windows and exterior insulating brick. Figure 9. View from the southwest as framing is nearing completion. (August 6, 2006) As was shown in the cross-section in Figure 8, the exterior cladding of the entire house and garage is an insulated brick product. A photo of the brick is shown in Figure 10. HEATING SYSTEM The active solar heating panels were installed on the south wall of the house. A view of the south is presented in Figure 12. Figure 12. View of the south side of the house. The active solar heating panels are being installed in a horizontal band between the lower windows in the basement and the windows on the main floor. Two of the glass cover plates for the solar panels are visible on the right of the wall. A closer photo of the active solar heating panels being installed is shown in Figure 13. Figure 10. View of the insulating brick product on the front of the garage. The garage door is on the left. (October 26, 2006) Figure 13. Active solar heating panels being installed. The absorber plates are mounted on the vertical. Double glazing was used.

A photo of a window installed in the East bedroom is shown in Figure 14. recycled stainless steel tank originally used in a brewery. Figure 14. Window installed in an East facing wall. The East, West and North facing windows are triple glazed with two low emissivity coatings and argon gas fill. The windows have wood frames with aluminum cladding on the exterior for low maintenance. A view of the inside of the windows is shown in Figure 15. These windows are in the basement in the approximate middle of the south wall. Figure 16. Stainless steel heat storage tank. The lower part of the tank has a dimpled appearance. This lower part is the external heat exchanger on the tank through which the propylene glycol and water mixture passes. The water in the tank is not used directly for hot water in the house. A small stainless tank inside the larger tank is used, along with a copper coil heat exchanger. This smaller tank and the copper coil heat exchanger are shown in Figure 17. Figure 15. South facing windows in the basement of the house. Note the wood frames for the windows. The space heating for the house is provided by a combination of passive solar heating, internal heat gains from electricity use and occupant heat, and an active solar space heating system. When additional heat is required, electric baseboard heaters will be used. A photo of the storage tank for the active solar heating system is shown in Figure 16. This 2350 litre tank is a Figure 17. Small stainless steel tank and copper coil heat exchanger used to transfer heat from the water in the large storage tank to the potable hot water.

The large coil and small storage tanks are used because the potable water will pass through the larger tank only once. A waste water heat exchanger is used on the house to recover heat from the drain water from the middle bathroom on the main floor. A photo of the copper heat exchanger is shown in Figure 18. Figure 19. Instantaneous Water Heater To provide space heating for the house, a fan coil incorporating a water to air heat exchanger is located adjacent to the large storage tank in the basement. A picture of the fan coil is shown in Figure 20. Figure 18. Copper waste water heat exchanger for the house. This unit recovers heat that normally would flow down the drain. If there is insufficient heat in the potable hot water after passing through the waste water heat exchanger and the solar storage tank heat exchanger, the water temperature is raised by an instantaneous electric heater. A picture of the instantaneous water heater is shown in Figure 19. Figure 20. The fan coil is shown on the left. It takes hot water from the large storage tank and uses the hot water to provide space heating through a forced air system. The fan on the forced air system is a brushless direct current motor. The fan coil can also take cooled water from the pilings beneath the house and use this cooled water for space cooling. ROOF WATER COLLECTION SYSTEM To reduce water consumption, the house has low flow shower heads, a front loading clothes washer, a water efficient dishwasher, and water efficient landscaping. To further reduce purchased water consumption, water is collected from the roof and stored in membrane storage tanks beneath the basement floor. A cross section of the house showing the location of the water storage tanks is shown in Figure 21. Figure 21. Cross section of the house showing the location of the plastic bladder cistern for rainwater storage in the crawl space.

The water collected from the roof will be used for two purposes: toilets and exterior landscape watering, neither of which uses require potable water. A photo of the pump that is used to lift water from the cistern to the end uses is shown in Figure 22. Energy Detective TM will be used. This device, which is connected to the main electrical panel, has a readout device that can be plugged into any outlet in the house. It will give an instantaneous readout of the electricity use in the home in both kilowatts and $/hour. Studies on the device have shown that it can reduce electricity use by about 10% to 15% compared with a group of homes that do not use the device. LIGHTING Almost all of the light fixtures in the home use compact fluorescent lamps. Figure 22. Water pump to supply the toilets and the exterior landscaping. ROOF SLOPE FOR FUTURE PHOTOVOLTAICS Because of the relatively high cost of a photovoltaic system (approximately $50,000), no attempt was made to use a grid connect PV system. The roof slope on the south side of the house, however, is suitable to add photovoltaic panels at a later date when costs are lower. An electrical wire was put in place into the attic to facilitate the future hookup of such a roof mounted PV system. Figure 23. Light fixtures in the kitchen/dining area with compact fluorescent lamps. Halogen lamps were used over the kitchen cabinets, as compact fluorescent lamps were not available in this style. Motion activated light emitting diode lamps were used on the risers of the staircase between the main floor and the basement. APPLIANCES Appliances chosen for the house are Energy Star rated where applicable. The major appliances have the following Energuide Ratings: kwh/year Dishwasher 242 Clothes Washer 247 Refrigerator 372 Freezer 479 Electric Range 453 Clothes Dryer 937 A voltage lowering device called the Green Plug TM will be used on the refrigerator and freezer to further reduce consumption. To assist the occupants to determine instantaneously their use of electricity, an innovative device called The Figure 24. Halogen Lamps over the kitchen cabinets. The refrigerator and electric stove are also shown.

INDOOR AIR QUALITY The three basic approaches being used are to reduce avoidable interior sources of offgassing, to provide clean outside air, and to use a continuous mechanical ventilation system with heat recovery. The use of a buried ground tube to preheat ventilation air was considered, but potential problems with condensation and mould growth in the buried tube led the design team to avoid this approach. No wall to wall carpets are used in the house. An innovative ceramic-topped but flexible floor tile is used in a large part of the living area of the main floor. An air to air heat exchanger (heat recovery ventilator) with low energy brushless direct current motors is being used. On low speed the wattage draw of the unit is 55 watts. The unit is located near the east wall to minimize energy losses in the ducts between the air exchanger and the outside. A continuous air flow of 30 Litres/second will be used in the house, which will have four occupants, two adults and two children under the age of 9. COMMISSIONING The following commissioning is to be done: 1. Building envelope air tightness 2. Commissioning of space heating system and controls 3. Commissioning of monitoring system 4. Commissioning of pumps for roof rainwater collection 5. Commissioning of toilet water consumption MONITORING PLAN FOR ENERGY AND INDOOR ENVIRONMENTAL QUALITY A computer based data logging system developed by National Instruments will be used for continuous measurements of temperatures, solar radiation, energy flows, water flows, carbon dioxide levels, and relative humidity in the house. The system is web-enabled for off-site data access. A schematic of the monitoring points for the house is shown in Figure 25. Figure 25. Monitoring Points In addition, spot measurements of volatile organic compounds, particulates, radon, and formaldehyde will be taken one month and twelve months after occupancy. ACKNOWLEDGMENTS The authors would like to thank the following for their contributions to the house: Homeowners Rolf and Shannon Holzkaemper Thermal Design Chris Richards Simulations Chris Richards Ventilation Rick Olmstead Contractor Lyle Rogne of Rogne Construction The Factor 9 Home: A New Prairie Approach could not have been developed without the strong support of its sponsors: Communities of Tomorrow, The Office of Energy Conservation of the Saskatchewan Government, Saskatchewan Research Council, Natural Resources Canada, and Canada Mortgage and Housing Corporation. Partners include the University of Regina and the City of Regina. Product sponsors include Panbrick Okamoto, Emercor, Watercycles, and Venmar.