The Saskatchewan Conservation House (211 Rink Ave, Regina, Saskatchewan, Canada [1] ) is an early exemplar of energy-efficient building construction that introduced best practices for addressing air leakage in houses. [2] It was designed in response to the energy crisis of the 1970s at the request of the Government of Saskatchewan. The Saskatchewan Conservation House pioneered the use of superinsulation and airtightness in passive design [3] and included one of the earliest heat recovery systems. [4] The house did not require a furnace, [5] despite prairie winter temperatures as low as −24 °C (−11 °F) at night. [6]
In 1977, when it was built at 211 Rink Avenue in the Walsh Acres neighborhood of Regina, Saskatchewan, Canada, [1] the house was the world's most airtight house. [7] [8] [9] The cost of the electricity to heat the house was estimated as $30–40 for a year. [10] [11] The house's building envelope continues to perform as designed, more than 40 years later. [2]
For its first two years, the Saskatchewan Conservation House could be viewed by the public as a model house. In 1978 as many as 1,000 visitors a week visited it. [12] The Saskatchewan Conservation House influenced the development of energy efficiency building codes both in Canada and internationally. It shaped the field of energy-efficient construction, including passive solar building design and the German passive house. [8] [9] In April 2015, Germany's Passive House Institute gave its designers a Pioneer Award for the design and construction of the house. [4]
In response to the energy crisis of the 1970s, the Government of Saskatchewan asked the Saskatchewan Research Council (SRC) to design and build a solar house that would be "appropriate for Saskatchewan". [13] [11] The house would have to be capable of staying warm despite short winter days and night-time winter temperatures of −24 °C (−11 °F). [6]
A committee was formed with participation from the Saskatchewan Research Council, the University of Saskatchewan, the Building Research Division of the National Research Council (NRC) of Canada, and others. Members included R.W. Besant, Rob Dumont, Dave Eyre, Harry Filson, Bill Gibbons, George Green, Hendrik Grolle, Dave Jennings, Garry Marvin, Deryl Thomson, and lead engineer Harold Orr. [13] [11] [6] [7]
One of the first steps taken by Orr's team was to estimate the energy requirements of powering a standard 1970s house with solar power. Their calculations showed that the water-based energy storage technology of the time was inadequate to meet the needs of such a house. The team chose a different approach, that of radically reducing the house's energy demand. [14]
The total energy consumption of a house reflects several factors relating to its building envelope: (1) heat loss through windows, walls, and ceiling, (2) heat loss through the basement, and (3) air leakage. [14]
As one of the principal designers of the Saskatchewan Conservation House, Orr suggested a radical increase in insulation of the walls, ceiling and foundation, and the use of airtight construction techniques. [14] [8] [9] Orr has compared the difference between the two approaches to designing a coffeemaker vs. designing a thermos bottle. A coffeemaker keeps things warm while it is plugged in and turned on, while a thermos stays warm once it is filled without adding more energy. [14] The resulting house incorporated three key elements: superinsulation, extreme airtightness, and one of the first heat-recovery ventilators. [15] [7]
At a time when most Canadian houses had 4-inch-thick (100 mm) walls with an insulation R-value of r-8, the Saskatchewan Conservation House had 12-inch-thick (300 mm) walls with r-40 insulation and a roof with r-60 insulation, [15] increasing the house's insulation to approximately six times compared to the standard. Rather than having a basement, it was raised off the ground to further prevent heat loss to the ground. [6] The raised floor system included a crawl space with r-20 insulation. [11] Orr estimated that suspending the floor above the soil level could mitigate 80 percent of the downward heat loss. [6]
At a time when single-panel windows were the norm [15] and high-grade windows were r-2, [11] the Saskatchewan Conservation House used triple-glazed windows in deep window enclosures. [15] [16] The designers also tried adding a system of shutters that could be used to prevent heat loss, but the shutters were not particularly successful. [11] The house was laid out to take advantage of the Sun when possible, with living accommodations and windows facing south. [6] Large trees were planted to the north to provide a wind buffer, while the south side was left clear to the Sun. [11]
To prevent air leakage and achieve extreme airtightness, Orr and his colleagues installed a vapor barrier themselves. [15] Local contractors did not have the expertise they needed for their experimental technique. [11] They built a double wall, using the outer wall for the structure and placing the vapor barrier on the internal wall, then adding inexpensive blown mineral fibre for insulation. [6] [11]
Because the house was extremely air-tight, the designers built an air-to-air heat exchanger to move fresh air into the house through a series of baffles. On the other side of the baffles, stale indoor air was pushed out. The design transferred heat from the warm exhaust air being released to the cold incoming air. [15]
The Saskatchewan Conservation House did not have a furnace. [5] The cost of electricity to heat the house was estimated at $30–40 for a year. [10] [11] An experimental solar heating system with a 17.9 m2 (193 sq ft) array of vacuum-tube solar collectors collected heat from sunlight during the day, storing it in a 12,700-litre (2,800 imp gal; 3,400 US gal) water tank insulated to about r-100. Pumps and heat exchangers could use the stored heat to heat the house at night or heat water. [11] Solar gains during the winter were small, so the angle of the array was optimised. [15] [6]
The Saskatchewan Conservation House was the most airtight house in the world at the time it was built. [7] Its conservation measures, such as insulation, airtightness, and its ventilation system, were highly effective. [17]
A blower door was used to obtain a standardized measurement of the number of times per hour that a fan could suck all of the air out of a house at a prescribed pressure of 50 pascals (0.0073 psi). At the time most new Canadian houses scored around 9 air changes per hour (ACH) at 50 Pa. On average, an existing Canadian home had 1,384 square centimetres (214.5 sq in) of air gaps, resulting in ratings of around 6.85 ach@50pa. In contrast, the Saskatchewan Conservation House achieved measures of 0.8 ach@50pa. [15] Air remained fresh due to the inclusion of an air-to-air heat exchanger that used waste heat from vented air to warm fresh air as it was moved into the house. [15]
The Saskatchewan Conservation House project faced challenges, including the government-mandated inclusion of a solar hot-water system that proved to be expensive and inefficient. [4] The solar component was new and experimental. It cost around $65,000 to build, more than the total cost for the rest of the house, which cost around $60,000. The prototype solar system was also extremely costly to maintain. Even though the electricity to power the system cost a few dollars a month, maintenance during its first year cost approximately $10,000. [11]
Orr's takeaway from the project was that:
Conservation is much less expensive than solar. For every dollar we spent on reducing heat loss from the house, with a better air barrier and more insulation, we saved at least $10 on the size of solar collectors and equipment needed to achieve the same thing. – Harold Orr, 2013 [6] [11]
The Saskatchewan Conservation House was used for two years as a model show house. It was then sold to a private owner, who removed the solar component. [4] Its building envelope continues to perform as designed, more than 40 years later. [2]
The Saskatchewan Conservation House became a model for low-energy house design. [17] [16]
Its design approach of treating the "house as a system" became the basis of a voluntary national building standard. The standard included r-20 insulation, blower-door ratings of 1.5 ach@50pa or better, incorporation of a heat-recovery ventilator, and use of non-toxic materials. The new standard was supported by Natural Resources Canada (NRCan) and the Canadian Home Builders' Association (CHBA). At the time, it was the most stringent standard in the world. It was introduced decades before green building initiatives such as LEED (Leadership in Energy and Environmental Design) and Built Green. [15]
The elements used in the project paved the way for the development of the Natural Resources Canada R-2000 standard and its integration into the Canadian national building code. [15] [18] They led to the establishment of new national energy conservation protocols, the Energuide Energy efficiency building codes, for use in Canadian buildings. [19] [20] Fourteen similar houses were constructed in Saskatoon in the mid-1980s, using principles from the Saskatchewan Conservation House. [19]
The Saskatchewan Conservation House also became a model for the international Passive House (Passivhaus) building energy efficiency standard. [21] [5] The Passivhaus standard was developed by Austrian physicist Wolfgang Feist and Swedish structural engineer Bo Adamson. After studying early superinsulated homes, including the Saskatchewan Conservation House, Feist stated a mathematical formula for the design of high-performance buildings, [15] which was published in his thesis Passive Houses in Central Europe (1993). [22] [23]
Feist's standard has two hard limits: airtightness of a building must meet or exceed 0.6 ach@50pa, and its total energy use for heating and cooling must not exceed 15 kilowatt hours (kwh) per square metre of floor area. A building built to this standard can reduce energy consumption by 80 to 90 percent, compared to conventional construction. It is well enough insulated that it does not require an "active" furnace or boiler, hence the term "passivhaus". [15] [5] Buildings are certified to the passivhaus standard. [15]
The first passivhaus to be built, in 1991, was the Darmstadt-Kranichstein Passive House, a row of four townhouses in Darmstadt, Germany. [15] Since then, the passive house approach has become influential in Germany and other areas of Europe. [4] [24] [25] In April 2015, Germany's Passive House Institute gave the designers of the Saskatchewan Conservation House a Pioneer Award for its design and construction. [4]
Ironically, adoption of the approach has been slower in Canada than in Europe. Canada's first passive house was assembled in Whistler, B.C., using prefabricated components from Austria, for use at the 2010 Winter Olympics. The building used about one-tenth of the energy of a comparable-size conventional building, with a heating cost of $280 a year in 2011. [15] In Saskatchewan, the first house to apply for official certification as a passive house was the Temperance Street Passive House, in 2016. It uses many of the principles that were introduced in the Saskatchewan Conservation House in 1977. [24] [25]
An autonomous building is a building designed to be operated independently from infrastructural support services such as the electric power grid, gas grid, municipal water systems, sewage treatment systems, storm drains, communication services, and in some cases, public roads.
In passive solar building design, windows, walls, and floors are made to collect, store, reflect, and distribute solar energy, in the form of heat in the winter and reject solar heat in the summer. This is called passive solar design because, unlike active solar heating systems, it does not involve the use of mechanical and electrical devices.
Thermal insulation is the reduction of heat transfer between objects in thermal contact or in range of radiative influence. Thermal insulation can be achieved with specially engineered methods or processes, as well as with suitable object shapes and materials.
A blower door is a machine used to perform a building air leakage test. It can also be used to measure airflow between building zones, to test ductwork airtightness and to help physically locate air leakage sites in the building envelope.
A low-energy house is characterized by an energy-efficient design and technical features which enable it to provide high living standards and comfort with low energy consumption and carbon emissions. Traditional heating and active cooling systems are absent, or their use is secondary. Low-energy buildings may be viewed as examples of sustainable architecture. Low-energy houses often have active and passive solar building design and components, which reduce the house's energy consumption and minimally impact the resident's lifestyle. Throughout the world, companies and non-profit organizations provide guidelines and issue certifications to guarantee the energy performance of buildings and their processes and materials. Certifications include passive house, BBC—Bâtiment Basse Consommation—Effinergie (France), zero-carbon house (UK), and Minergie (Switzerland).
Passive house is a voluntary standard for energy efficiency in a building, which reduces the building's ecological footprint. It results in ultra-low energy buildings that require little energy for space heating or cooling. A similar standard, MINERGIE-P, is used in Switzerland. The standard is not confined to residential properties; several office buildings, schools, kindergartens and a supermarket have also been constructed to the standard. The design is not an attachment or supplement to architectural design, but a design process that integrates with architectural design. Although it is generally applied to new buildings, it has also been used for refurbishments.
Sustainable architecture is architecture that seeks to minimize the negative environmental impact of buildings through improved efficiency and moderation in the use of materials, energy, development space and the ecosystem at large. Sustainable architecture uses a conscious approach to energy and ecological conservation in the design of the built environment.
Superinsulation is an approach to building design, construction, and retrofitting that dramatically reduces heat loss by using much higher insulation levels and airtightness than average. Superinsulation is one of the ancestors of the passive house approach.
The Saskatchewan Research Council (SRC) is a provincial treasury board crown corporation engaged in research and technology development on behalf of the provincial government and private industry. It focuses on applied research and development projects that generate profit. Some of its funding comes from government grants, but it generates the balance from selling products and services. With nearly 300 employees and $137 million in annual revenues, SRC is the second largest research and technology organization in Canada.
A Zero-Energy Building (ZEB), also known as a Net Zero-Energy (NZE) building, is a building with net zero energy consumption, meaning the total amount of energy used by the building on an annual basis is equal to the amount of renewable energy created on the site or in other definitions by renewable energy sources offsite, using technology such as heat pumps, high efficiency windows and insulation, and solar panels.
Renewable heat is an application of renewable energy referring to the generation of heat from renewable sources; for example, feeding radiators with water warmed by focused solar radiation rather than by a fossil fuel boiler. Renewable heat technologies include renewable biofuels, solar heating, geothermal heating, heat pumps and heat exchangers. Insulation is almost always an important factor in how renewable heating is implemented.
Domestic housing in the United Kingdom presents a possible opportunity for achieving the 20% overall cut in UK greenhouse gas emissions targeted by the Government for 2010. However, the process of achieving that drop is proving problematic given the very wide range of age and condition of the UK housing stock.
Seasonal thermal energy storage (STES), also known as inter-seasonal thermal energy storage, is the storage of heat or cold for periods of up to several months. The thermal energy can be collected whenever it is available and be used whenever needed, such as in the opposing season. For example, heat from solar collectors or waste heat from air conditioning equipment can be gathered in hot months for space heating use when needed, including during winter months. Waste heat from industrial process can similarly be stored and be used much later or the natural cold of winter air can be stored for summertime air conditioning.
Building insulation is material used in a building to reduce the flow of thermal energy. While the majority of insulation in buildings is for thermal purposes, the term also applies to acoustic insulation, fire insulation, and impact insulation. Often an insulation material will be chosen for its ability to perform several of these functions at once.
The Pennyland project was one of a series of low-energy building experiments sparked by the 1973 oil crisis. It involved the construction of an estate of 177 houses in the Pennyland area of Milton Keynes, Buckinghamshire, United Kingdom. It compared possible future UK building efficiency standards with newly introduced Danish ones.
Air changes per hour, abbreviated ACPH or ACH, or air change rate is the number of times that the total air volume in a room or space is completely removed and replaced in an hour. If the air in the space is either uniform or perfectly mixed, air changes per hour is a measure of how many times the air within a defined space is replaced each hour. Perfectly mixed air refers to a theoretical condition where supply air is instantly and uniformly mixed with the air already present in a space, so that conditions such as age of air and concentration of pollutants are spatially uniform.
Zero-carbon housing is a term used to describe a house that does not emit greenhouse gasses, specifically carbon dioxide (CO2), into the atmosphere. Homes release greenhouse gases through burning fossil fuels in order to provide heat, or even while cooking on a gas stove. A zero carbon house can be achieved by either building or renovating a home to be very energy efficient and for its energy consumption to be from non-emitting sources, for example electricity.
Building airtightness can be defined as the resistance to inward or outward air leakage through unintentional leakage points or areas in the building envelope. This air leakage is driven by differential pressures across the building envelope due to the combined effects of stack, external wind and mechanical ventilation systems.
Zero-heating building or nearly zero-heating building (nZHB) is a building having essentially zero heating demand, defined as having heating demand, Q’NH, less than 3 kWh/(m2a). The zero-heating building is intended for use in heating-dominated areas. The purpose of the zero-heating building is to supersede net-zero energy buildings as a way to bring building-related greenhouse gas emissions to zero in the EU. Zero-heating buildings address flawed net-zero energy buildings: the requirement for seasonal energy storage, in some cases poor comfort of living and narrow design options.
Harold Walter Orr is a Canadian mechanical engineer known for his work on energy-efficient construction and air leakage in houses, in particular the prioritization of energy demand reduction over active systems through the use of superinsulation and airtightness in passive design. Among Orr's major technical works are Design and construction of low energy houses in Saskatchewan (1982) and Energy efficient housing on the prairies (1982).