Installing airtight windows and doors is a necessity today. It is enforced by building regulations, which are becoming stricter every year. The growing bills for heating are also an incentive to choose construction with high thermal insulation parameters. What parameters must windows and doors have in 2023? We shall check.
If you are building a house or planning to build one, it is essential to know the current regulations. Your project must meet the requirements of the Building Act and the current technical conditions. These actually change from year to year - the last change was in September 2022.
The technical conditions devote a lot of space to the issue of thermal insulation. Polish and European Union regulations are clear. Houses are to be made more and more energy efficient, and therefore more and more airtight, in order to minimise the energy required to heat them. Which parameters in the technical conditions are particularly worth paying attention to?
Thermal transmittance - parameters and regulations 2023
The most important and absolutely key parameter you need to consider when building a house is the heat transfer coefficient (U). It tells you how much heat is lost through a square metre of surface area (e.g. windows or doors) in one hour.
In a nutshell: the U-value shows how much heat your home loses. The lower this parameter is, the better. This means that the building is airtight and that less fuel - coal, wood, gas, etc. - is needed to heat it.
The maximum heat transfer coefficient is specified in the current technical conditions. The regulations in force in 2023 state that this parameter should be at most:
- external walls - 0.2 W/m2K;
- floors - 0.3 W/m2K;
- ordinary windows and balcony doors - 0.9 W/m2K;
- skylight windows - 1.1 W/m2K;
- roof - 0.15 W/m2K;
- external doors - 1.3 W/m2K.
How have these values changed over the years? For ordinary windows, as recently as 2017 the required thermal transmittance was 1.1 W/m2K, and for roof windows it was 1.3 W/m2K. So the regulations clearly show that year by year the requirements for the thermal insulation of homes, including window and door frames, are getting higher and higher.
Take into account that the parameters quoted above are the absolute minimum. The lower the thermal transmission rates, the more airtight and energy-efficient the house.
It is therefore worth choosing products with the lowest possible heat transfer coefficient, even if this involves a higher cost for such solutions. This is an investment that will quickly pay off in lower heating bills!
How to achieve low thermal conductivity coefficient?
Key window technology!
The heat transfer coefficient is greatly influenced by good thermal insulation. It consists of many different factors: the choice of house construction technology and wall materials and their thermal insulation, absence of so-called thermal bridges, choice of ceiling, roof material and its insulation, as well as appropriately sealed windows and doors.
Does the material from which the windows and doors are made, matter? Not as much as their construction itself. PVC windows, wooden windows and aluminium windows can have high thermal insulation performance.
If you're looking for windows with a low thermal transmittance, pay attention to the manufacturer's technology. Let's take a look at Elegant 76 windows from the manufacturer Lanko. They are distinguished by 6-chamber technology, providing excellent thermal insulation up to 0.94 W/m2K.
The Elegant 76 windows also use three peripheral gaskets, which ensure maximum thermal insulation, air permeability and water tightness parameters.
It is also worth mentioning that the windows offer the possibility of using a structure with Forthex technology. This is a composite reinforcement (body made of durable PVC reinforced with steel bars, filled with foamed PVC), which further improves the thermal insulation parameters of the window.
What does good thermal insulation of an entrance door depend on?
From 2022, the heat transfer coefficient for external doors has been improved. It is now a maximum of 1.3 W/m2K.
It is worth remembering that doors can reduce heat loss and thus reduce the energy requirements for heating the house. When choosing a door model for your home, it is therefore essential to pay attention to whether it meets the current thermal insulation conditions.
Example? The Elegant 76 entrance door system from Lanko. Their heat transfer coefficient is 0.79 W/m2K.
Such good parameters are the result of the door's modern manufacturing technology and an advanced sealing system with an internal rebate seal in the leaf and an external frame seal including a centre seal. In addition, the door is available with a low, warm aluminium threshold.
