Are there windows that can meet the Passivhaus standard?
Yes, there is. But, for windows to meet the Passivhaus standard, they must have the following performance features:
- A U-value of 0.8 W/m²k or lower, demonstrating that the entire window unit is highly insulating.
- A G-value of 0.5 or more. G-values measure the solar transmittance factor, and a value of 0.5 or more demonstrates that a net heat gain of 35% is possible.
What is the Passivhaus standard?
The Passivhaus (Passive house in English) standard is a building design code that was set up for the purpose of building homes that can maintain consistently comfortable temperatures throughout the year without the aid of an air conditioning or heating system.
Homes that achieve the Passivhaus standard consume 90% less energy than homes built to Building Regulations standards.
How does passive house work?
The overall idea behind passive houses is that they reuse ‘free’ heat that is generated from household appliances, lightbulbs and other heat sources in the home in order to keep it warm. Therefore, they are constructed to be very well insulated and airtight, which ensures this ‘free’ heat is retained in the home.
So how is the Passivhaus standard achieved for windows?
In order for windows to achieve the Passivhaus standard, they must be fitted with triple glazing. However, they must also have highly insulating frames and good air tightness. Any additional features that actively prevent thermal bridging also help windows to achieve the standard.
Here at T&K, our uPVC windows can achieve U-values 0.8W/m2k, which means they adhere to Passivhaus standards.
Can you open windows in a passive house?
Yes, they can be. Just because Passivhaus standards require windows to be built to a certain degree of airtightness doesn’t mean that they can’t be opened. Like with any other windows, they can be opened to ventilate the home as you see fit.
The role of glazing when creating passive houses
The windows/glazing play an essential role in creating passive houses because windows allow for large amounts of ‘free’ heat to enter the building as a result of solar gain. They also play an important role in how much heat is then able to escape.
To maximise solar gain during the winter, lots of windows/glazing should be installed at the south-facing side of the property too. However, on north-facing homes, glazing should be kept to a minimum. This is because the lack of direct sunlight means heat generated from solar gain will be minimal.
Excellent deals to help you edge closer to the Passivhaus standard
We’re currently offering you the chance to get 3 windows for £1,800! You can use this deal to help get your house closer to the Passivhaus standard. Plus, we’re offering deferred installation for up to 3 months to help with the ongoing coronavirus pandemic.
If you’d like to take advantage of one of our great finance packages, such as pay a £99 deposit and then nothing until 2021, when doing this, this is possible too. For more information, call T&K Home Improvements on 0800 622 716 or contact us online.
