What You Need to Know About Passive Homes

Saving money on energy bills has never been easier than with the rigorous standards and concepts presented by Passive Houses. The Passive House was introduced in 1991 by Dr. Feist in Germany and is a concept used more and more commonly in construction of homes and buildings today.

The Passive House uses efficient construction and materials to conserve as much energy as possible. A Passive House takes into account the heating and cooling systems of a home, its orientation and ventilation to keep the house’s temperature as controlled as possible (Pinwheel Builds). Essentially, passive homes and buildings look to maximize energy gains while minimizing their loss of energy.

Read more below to learn about the benefits that contribute to the growing success of the Passive House!

Require Air-tight Insulation

The first step to achieving a Passive House is to ensure that the air envelope of the home is extremely tight. Walls must be constructed in such a way that excess vapour travels through the walls but hot air does not. A tight air envelope will ensure that as much wanted heat is retained within the home as possible, without the use of fossil-fueled heating technologies. The heat inside the home comes primarily from the sun, appliance use and body heat. This concept of heat retention is especially useful in the winter months when keeping heat inside the home is a priority for comfort.

Thermal Mass Usage to Redirect Heat

The thermal mass of a home is another key element to the successful designation of a Passive House. A thermal mass is a material that retains heat, such as concrete, brick, stone and tile. They absorb sunlight during the heating season which keeps the house cool and release it slowly during the evening and work to warm the home (U.S. Department of Energy).

Minimizing Thermal Bridging in a Passive House

The R-Value is a measure of how well your insulation resists heat flow across the material in question. The higher a material’s R-Value, the greater its insulating power is. However, insulation is more than its R-Value due to thermal bridging. Thermal bridging occurs when a poorly insulated material allows an easy pathway for heat flow across a thermal barrier. One of the most common thermal bridges readers may be familiar with are wall studs. For example, a wooden stud may allow heat to flow through it 3x faster than its surrounding insulation. Some thermal bridge cures include reducing the amount of wall studs, using structural insulated panels or to apply strips of insulation over the wood studs to provide a thermal break (North).

Reducing Energy Costs for Home Owners

Home owners have all claimed that a passive home has saved them on energy costs. In a survey conducted in Milton Keynes, England, no residents reported that the performance of their home was either unsatisfactory or very poor. 86.4% of respondents said that they now spend less on fuel. 47% of this population spend 21-40% less while 26.3% spend 41-60% less on energy costs compared to a similar sized home without passive energy standards. These numbers are substantial and over an extended period of time, will save the home owners more money on energy than they likely thought possible.

Properly Orientated Homes and Windows

The orientation of a house is next in importance after the air-tight envelope of the home. People may say that their home was designed using passive solar principles, which indicates that they have orientated their home on a North-South axis with most windows facing the South. Almost all Passive Houses are designed this way, and many modern homes are chosen in this orientation to maximize passive solar heat gain. Windows on the South side should be detailed with overhangs on the exterior in order to allow as much sun as possible to come into the home during the winter months when the sun is at a low angle and the overhangs will block the high summer sun in the hotter months  (Pickering).

Incorporation of Heat Recovery Ventilation (HRV)

A heat recovery ventilation system uses heat or air exchangers and employs a counter-flow heat exchange. HRV provides fresh air and climate control within a Passive House. It functions on the principle of using the heat in the outgoing stale air to warm up incoming fresh air. The true science in an HRV lies in its heat exchange core that transfers heat from the outgoing stream to the incoming stream. As the stream of heat moves through, heat is transferred from the warm side of each passage to the cold without the two of them actually mixing. Dependent on the model, an HRV can recover up to 85% of the heat in the outgoing airstream. HRV’s also come fitted with filters that keep pollutants out of the home. These systems are ideal for tight, moisture-prone homes because they replace the humid air with dry fresh filtered air. In drier climates, an energy recovery ventilation system may be used, which dehumidifies the incoming fresh air stream (Popular Mechanics).

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The concept of a Passive House and minimizing energy requirements on a home are a step in the right direction for those wishing to construct a custom modern green home. However, it is important to note that a Passive House does not account for any of the materials or insulation to be environmentally friendly and only considers the energy efficiency of a building. A home that aims to be environmentally conscious would ideally contain materials that promote the health of its habitants and the sustainability of the environment. Companies such as BONE Structure encompass as many aspects of an environmentally conscious building as possible. From incorporating concepts from Green Buildings, Net-Zero Energy Homes, LEED certification and passive homes in each personalized project, a BONE Structure home is the best choice for the environment. At BONE Structure, a home is constructed with as many local, non-toxic and recyclable or recycled materials as possible.

BONE Structure not only works to minimize energy requirements on a home, but also work very hard to create little to no waste and source as environmentally conscious as possible. A BONE Structure home helps home owners achieve a completely sustainable lifestyle in a long lasting home with energy savings that will extend for the entire lifetime of the house.