OTTAWA, ONTARIO--(Marketwire - Sept. 21, 2012) - Chances are that if you live in one of the million wartime, postwar or "victory" houses built between 1945 and 1960, you may be paying more in heating and cooling costs than if you lived in an energy efficient new home. Older homes can be draughty and cold in the winter or uncomfortably hot in the summer. However, moving can be costly and disruptive, especially if you love your existing home and neighbourhood. So why not consider an energy efficient renovation?
Energy efficient retrofits can include a range of options and costs, depending on the extent of your retrofit. Often, more extensive energy efficient retrofits can't be justified by the energy cost savings alone. However, by including energy efficient retrofits when undertaking other needed renovations and repairs, such as siding repairs, window replacement or additions, you can more affordably reduce energy costs while addressing other needs. In the case of wartime houses, many are at the point where renovations are required and this represents a good opportunity to include energy efficiency measures to improve the performance of iconic house type.
Recently, there have been several initiatives that explored the energy savings possible in wartime houses. The Now House™ project in Toronto is a successful example of how a 60 year old post war 1.5 storey home can be modernized to the same level or better than new construction - without losing the charm and appeal of the original house. Renovated as a part of Canada Mortgage and Housing Corporation's EQuilibrium™ Sustainable Housing Demonstration Initiative, the home showcases a number of innovative features that increase energy efficiency, improve air quality and improve the functionality of the interior of the home. Five other wartime houses were also recently renovated in Windsor Ontario to better understand the costs and full range of benefits attributable to progressively more aggressive packages of energy efficiency and renewable energy measures.
A comparison of the pre and post retrofit energy consumption and costs of the 5 houses in Windsor revealed electricity savings between 17 - 43% and natural gas savings between 43-60% depending on the extent of energy efficiency and renewable energy retrofits. Retrofit costs ranged from $18,000 for the baseline retrofits to $40,000 for a more full range of energy efficient and renewable energy features.
Many of the energy retrofits were applied to the exterior of the house so that the occupants could remain in the homes during the renovations. Adding insulation to the exterior walls from the inside of the house can be messy and disruptive as extensive demolition, repair and refinishing is needed. Room size can also be reduced. By renovating from the exterior, little damage was done to the interior walls. An added bonus to this approach is that roofing and exterior cladding materials can be replaced with newer products which can improve the home's "curb appeal" while improving the performance of the house.
Essential Strategies to Energy Savings
The original roof, exterior walls, and portions of the basement slab of the NOW House™ were opened up to allow create more space for insulation and to provide access for air sealing work. Thermal insulation levels in the attic, exterior walls, foundation, and basement slab were increased to R-40, R-39, R-25, and R-10 respectively, and air leakage was significantly reduced making the house warm, and cosy in the colder months and cooler in the summer. An energy efficient heat recovery ventilator (HRV) was installed to maintain good indoor air quality in the retrofitted home.
All existing windows were replaced with energy efficient, fibreglass framed, double glazed, argon filled windows. The south facing living room window was also enlarged to allow more daylight and passive solar energy into the home to decrease space heating and lighting energy consumption. The sun is kept out during the hot summer months by using an exterior solar blind that blocks 80% of the sun's rays.
Damp basements with low ceiling heights are often found in older homes. The NOW House™ team was able to add another 8 inches to the basement height by removing the original concrete slab, excavating deeper into the ground and then installing gravel, a poly vapour barrier, extruded polystyrene board insulation and radiant floor heating prior to pouring the new concrete floor. This new space provides a comfortable, warm recreation room for a house that otherwise had limited space to grow.
Other energy efficiency measures in the NOW House and Windsor projects included the installation of high efficiency furnaces and domestic hot water heaters, ENERGY STAR appliances, electricity producing photovoltaic systems.
For more information on the NOW House and Windsor wartime housing retrofit projects, visit CMHC's website (www.cmhc.ca) or call 1-800-668-2642. For over 65 years, CMHC has been Canada's national housing agency and a source of objective, reliable housing information.
For over 65 years, Canada Mortgage and Housing Corporation (CMHC) has been Canada's national housing agency, and a source of objective, reliable housing information.