What windows and doors to choose to meet the requirements of passive construction? You will find out in our article.
A solution for our times
Galloping prices for energy carriers, combined with a growing awareness of climate change caused by CO2 emissions, have made passive buildings increasingly popular in recent years. These houses are distinguished by their minimal heating requirements. The energy efficiency of such buildings is not only the result of the use of ecological, renewable energy sources, such as photovoltaic installations, but also the use of external partitions, especially windows and doors, which are characterized by very good insulation parameters.
Due to rising energy prices and increasing environmental awareness, passive solutions are gaining popularity
© Finstral / Marco Vega
First of all, insulation
The basic premise of passive construction is to reduce as much as possible the demand of buildings for the energy required to heat them. This goal can be achieved, among other things, through the proper location of the building in relation to the sides of the world, so as to take maximum advantage of solar radiation. The proper placement of windows, i.e. designing large glazing on the south side, contributes to lower energy consumption and reduces the use of artificial light. However, just using the properties of the sun is not enough for us to talk about a passive building. Such a building, first of all, must be excellently protected against heat loss. This is greatly influenced bywoodwork. According to the National Fund for Environmental Protection and Water Management, heat losses, for which windows are responsible, reach 23.1-36.3%. That is why it is so important to bet on the highest quality solutions that provide high thermal insulation.
Passive construction aims to reduce the demand for energy needed to heat the house
Photo: Bartosz Makowski/Ladny Dom
What is the Uw coefficient?
When choosing windows for a passive building, you need to pay attention to the Uw value. It represents the amount of heat that passes through each square meter of the window when the difference between the temperature inside the building and the prevailing temperature outside is equal to one kelvin. The lower the Uw, the more energy-efficient the window. For example, energy-efficient windows have a heat transfer coefficient with a maximum permissible value of 0.9 W/m2K. For passive windows, Uw must be less than or equal to 0.8 W/m2K. In passive houses, however, we should aim for Uw of 0.6 W/m2K. Also pay attention to the types of glazing. Passive windows often have double or even triple glazing with low emissivity and gas filling the space between them. The glazing of passive windows is also often coated with a low emissivity layer, which minimizes heat emission to the outside while allowing solar energy to penetrate into the building. It is also important that passive windows are carefully sealed, so that there are no air leaks that can lead to heat loss.
The lower the Uw, the more energy-efficient the window
Photo: Bartosz Makowski/Ladny Dom
What material are passive windows made of?
The most popular passive windows are made of durable PVC. This material has low thermal conductivity and is easy to maintain. Modern PVC profiles are often reinforced with steel or fiberglass, which increases their stability and durability. However, in spite of appearances, aluminum systems too, thanks to the use of appropriate insulating materials, can have excellent heat transfer parameters. In addition, aluminum profiles can be given a variety of shapes. As a result, they can be used to build various types of windows, including glass facades, which, when properly arranged, will be able to optimally illuminate and reheat rooms.
Passive windows are made of PVC or aluminum
© AdamS
Passive doors
Passive doors, like windows, are designed to minimize heat loss. They are installed as exterior doors, as they are the ones that absorb the most cold and are the main barrier against cold air getting inside. In addition to a high standard of thermal insulation, passive doors also protect against moisture. The most common passive doors are made of steel, aluminum or high-quality wood.
Passive doors, like windows, prevent heat loss
© Aluprof
Are you building a house? Check out our tips on door joinery
Compiled by:KATARZYNA SZOSTAK
