Energy-efficient – this describes a passive house in a nutshell. That’s because it makes use of very little energy for heating or cooling. With this structure, you’re sure to be comfortable while reducing your heating costs by as much as 80% to 90%.
While newer homes come with designs that make them passive, the older ones usually don’t have this. Although this is the case, you can transform your current abode into a passive house with the help of passive enthusiast roof repair experts. Calgary renovation companies are now proactive suggesting these types of homes in their services.
With many Canadian provinces mandating this type of design, it’s time that you get started right away.
What Makes a Passive House?
Before you have your home transformed, it’s best to know first the essential features that are required of a passive house:
One of the main goals of a passive home is to reduce air leakage. The standard air changes per hour (ACH) for a new home is 0.6, meaning it should not leak air that is 0.6 times its volume per hour. For retrofitted homes, the desired ACH is 1.
To test your home’s air leakage rate, your contractor will conduct a blower door test to determine the ACH.
Unfortunately, in most homes, the ACH is 3-5. This means that three to five times the overall volume of air leaves your home on an hourly basis.
In the olden days, this was promoted because it is deemed to help bring fresh air inside. Today, it results in the loss of heated or cooled air instead.
To make things worse, this can contribute to molds because of wall cavity condensation.
In provinces such as Ontario, the use of heat recovery ventilators is now required for all homes.
The downside that it only has to be 50% efficient, so making an old home airtight is still required to minimize loss of heated or cooled air.
That said, a sound ventilation system is still useful as it can help maintain air quality and moisture in the home. Most of these contain energy recovery systems that can heat or cool the air coming inside.
According to the building code, new homes need to have certain insulation grades. That’s R22 for the wall, R32 for the roof, and R10 for the below slab.
In some areas, the requirements are higher – R75 for the wall, R110 for the roof, and R40 for the below slab. For old homes that need to be retrofitted, the requirement is R48 for these three areas.
Considering the carbon dioxide created during the production process, many construction companies are lobbying for the use of renewable insulation materials.
One good example is cellulose, which makes use of recycled wood fiber. At the same time, it can help remove some of the carbon from the atmosphere.
The right windows are vital for each passive house.
In essence, these should be triple-glazed with an R12-equivalent insulated frame. With the help of such materials, your home can achieve a high-temperature interior pane.
For example, you get to feel a comfy 17°C inside even if it’s 25°C outside. For some triple-glazed windows, you can achieve as low as 12°C for the same exterior temperature.
Apart from the type of windows, they should also be oriented to make great use of the sun’s heat during winter.
Transforming Your Old Home into a Passive House
Now that you know what goes into a passive house, it’s time that you got yours retrofitted.
When you undergo retrofitting, you can expect the following changes to be done:
The repairmen will need to install extra insulation, as well as vapor-tight or airtight permeable layers. As such, they have to remove the interior or exterior finish of the walls, whichever is more economical for your part.
They will also need to source doors and windows to use for your retrofitted home.
If you have an attic, it will require the installation of an airtight or vapor-tight permeable membrane. If you have none, your house will still need an additional thermal layer for the interior.
For a cathedral-design ceiling, the contractors can build it down to meet the required R-value. However, if you have a flat ceiling, you’ll need a vacuum panel as it can provide a thermal barrier without affecting ceiling height.
If you have a usable basement, a vacuum panel is needed to create a thermal barrier as it will help avoid losing height.
If your home doesn’t have a basement, a thermal layer is still needed for the present floor cavity.
Passive House Refitting According to Home Type
A home repair company will tailor the reconstructions according to your home type:
Townhouses and Brownstones
These are some of the best homes to retrofit because they have big walls. At the same time, there are houses on either side, so temperature control is not an imposing problem.
In Brownstones, basements are packed enough that not much heat is lost into the ground. That said, these homes will only need changes in the roof and the exposed end walls.
This home can be made more airtight with the installation of an envelope around the unit.
It’s essential to separate this material from the outside and most of the apartment building. It’s also vital to have as much insulation as possible to preserve thermal comfort within the home.
For this house, all sides – including the attic and basement – need to be retrofitted. Most of the windows may need to be replaced, while the roof and attic should have a lot of insulation.
Again, having tight envelopes will help counteract the air loss brought about by the windows.
A passive home is one of the best investments you could ever have. It can keep you warm during winter and cold during summer. More importantly, it can help you cut heating costs by as much as 90%!
If you want to save money – and Mother Earth in the process – then it’s time you get your old home retrofitted as soon as possible.