Building or Buying Your Sustainable Home
The R-2000 Standard for Energy Efficiency
by Rolf Priesnitz
If you’re interested in buying a new green home in Canada, one of the most accessible ways is to look for one that meets the R-2000 Standard. Although these don’t tend to be cutting-edge homes, they’re still greener that most of what else is on the market.
The R-2000 Program is based on research from the 1970s that resulted in the “house as a system” concept, which was a major evolution in building science. It recognizes that the flow of air, heat, and moisture within a home all work together so that if you make changes in one area, it will affect other areas. The actual R-2000 Program was created in 1981 as a partnership between the Canadian Home Builders’ Association (CHBA) and Natural Resources Canada to begin moving this concept into the marketplace. Since then, thousands of homebuilders, building inspectors, plan evaluators, and other industry professionals have been trained to the standard and thousands of homes have been built and certified.
The R-2000 technical requirements involve three main areas of construction: energy performance, indoor air quality and environmental responsibility.
As a performance-based standard, it sets criteria for how a house must perform, rather than specify exactly how it must be constructed. The builder is free to choose the best and most-cost effective approach for each home – construction techniques, building products, mechanical equipment, lighting, and appliances.
One of the most important aspects is the energy target for space and water heating. The target is calculated for each house, taking into consideration size, fuel type, lot orientation, and location. Typically, R-2000 homes will use approximately thirty percent less energy than a comparable non-R-2000 home.
In order to achieve these energy savings, every R-2000 home is designed and built to reduce heat loss and air leakage. Extra insulation, energy-efficient windows and doors, and careful air-sealing are standard features. A mandatory blower door test is used to measure the airtightness of the building envelope to ensure that air leakage does not exceed the rate set out in the R-2000 Standard.
The mechanical systems for heating, cooling, and ventilation are chosen for efficiency and performance. Natural gas, propane, oil, or electrical systems are all permitted under the Standard which also allows for more advanced systems such as integrated space and hot water heating systems, heat pumps, and solar-assisted systems.
R-2000 construction always includes controlled ventilation to maintain good indoor air quality. Every R-2000 home must have a mechanical ventilation system to bring fresh air in from the outside and exhaust stale air to the outside. Most R-2000 builders use a heat recovery ventilator, or HRV, to provide continuous balanced ventilation. In winter, HRVs use the heat from the outgoing air to preheat the incoming air; in summer, this process is reversed.
To further protect the indoor air quality, R-2000 builders use building products specifically aimed at reducing chemicals, dust, and other indoor air pollutants. This includes products such as EcoLogo-approved paints, varnishes, and floor finishes; low-emission cabin- ets; or the use of hardwood floors.
The R-2000 Standard also recognizes the importance of resource conservation, both during the construction of the home and later during the ongoing operation of the home. Water-saving toilets, showers, and faucets are used exclusively. Builders are also required to use materials with recycled content.
Although these standards aren’t overly ambitious in terms of the quickly developing green building industry, houses built to them are relatively common. Many of Canada’s large builders are licensed R-2000. Not uncommonly, R-2000 is offered as an option with a company’s model plans. You will also find R-2000 builders among the smaller custom builders. Some modular home manufacturers are also licensed to build R-2000 homes.
In 1994, the CHBA established the EnviroHome standard. Each year the EnviroHome designation is given to a select number of new home projects across Canada. To qualify, each home must be certified to the R-2000 Standard and include additional air quality and environmental features beyond what the R-2000 Program requires.
Rolf Priesnitz is the founder and Publisher of Natural Life Magazine, and has over 40 years experience in the construction industry.
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