On a project currently under construction we discovered the improper installation of the vapour barrier at electrical outlets done during a previous renovation. The vapour barrier is not sealed to the outlet using a pre-manufactured outlet box. Instead there are numerous holes for air and moisture to enter and exit the home through the exterior wall. This can lead to mould and rot issues.
When on site reviewing projects under construction we review to ensure that contractors conform to the requirements of the contract documents (a.k.a. drawings and specifications). Two of the most important items to review for proper installation are the air and vapour barriers. These two membranes work hand-in-hand with properly balanced heating and cooling systems and their continuity are critical for providing an air-tight home, reducing risk of mould, and decreasing energy consumption.
According to John Straube, principal of Building Science Corporation and professor at the University of Waterloo in Ontario, air leaks can be responsible for up to one third or more of the energy loss of a home. Air leaks are caused by pressure differentials between the interior and exterior of the home. These differentials are caused by three factors: wind, fans and the stack effect. For example, when wind pushes on the house the leeward side becomes negatively pressurized, drawing warm, damp air from inside the home out through holes in the walls. When this warm, damp air is drawn through the exterior walls of the home, if it is colder outside than it is inside the water vapour in the air will condense inside the wall. Over time this can cause mould and rot. Similarly, the stack effect works on the principal that warm air rises. Like a large chimney, air and heat will escape through holes and cracks of the roof of a house based on the upward air movement. If not sealed properly, moisture can build up in attic and ceiling spaces.
There are many rebate an incentive programs available throughout Canada that support sustainable and energy efficient renovation and new construction. Unfortunately the majority of programs are available for commercial development or multi-family dwellings including townhomes and condominiums.
For the typical homeowner based in Toronto, the current options are very limited. For approximately five years the Federal Government ran a very successful program called the Eco-Energy Retrofit. This program provided up to $5,000 for improving the energy efficiency of your home including installation of new windows, adding wall insulation, and improving heating and cooling equipment. The incentive money was relatively simple to receive as long as a prescribed process was followed. Regrettably, this program was phased out in March of 2012.
Integrated into the 2011 Federal Budget, the government announced yesterday a one-year extension to the Eco-Energy Retrofit program for home owners. If you live in a drafty old house and feel like you are paying too much for your heating and cooling, the program can help offset the costs of upgrading building insulation, weather stopping, doors and windows. However before any of the renovations start, make sure that a qualified engineer of energy auditor tests your home in its current state to create a benchmark reading for comparison. If the drywall is already ripped off, you will not be able to conduct the test, and thereby become ineligible for the program. For additional information, refer to Natural Resources Canada's website. For information and suggestions on how to improve the energy performance of your home, contact KHA Design.
The Ontario Power Authority is offering up to $650 worth of incentives for homeowners to replace their existing furnace and/or air conditioning unit with new, Energy Star certified heating or cooling systems. According to the Power Authority, up to 60% of a typical home's electricity bill is devoted to heating and cooling. With the continual rise in energy costs and another hot, humid summer expected for Ontario, installing a new system can help reduce utility bills and the home's draw on our shared natural resources. The offer is valid only in Ontario between January 1, 2011 and December 31, 2011. For details, refer to the Ontario Power Authority's website.
The Masonry heater goes by many different names; Finnish Fireplace, Wood Heater, Kachelofen, Grundofen, Varaava Takka, Tile Stove and Ceramic Stove among others. All of these names refer to a large, specially-constructed fireplace that uses small amounts of fuel and is capable of heating an average family home. Although not always appropriate in a retrofit application, in the cold Canadian climate they are a sustainable home heating alternative in new home construction.
Masonry heaters first appeared in Northern Europe in the early 16th century. Historically, they were used in the kitchen, combining a stove, oven and seating areas. Located in the center of the home, they were fired twice daily for the preparation of meals and heating. The heaters were in all homes regardless of social status; however they varied aesthetically from white wash clay to ornate masterpieces.
Kate Harrison is a licensed architect and is the principal of KHA.