When to use understructure (klinaryt, purenit)?
When a window is planned to be placed directly on the foundation, the understructure plays key roles in ensuring the stability, insulation and durability of the entire window structure. Therefore, in any case where the window is in direct contact with the ground, we recommend using an understructure. Here is a detailed description of why and how to use understructure in such a case:
- Ensuring structural stability: Placing the window at foundation level requires special attention to stability, as foundations are subject to various structural movements (e.g., ground settlement, tectonic movements). Understructure helps spread the load of the window over a larger area, which reduces the risk of damage to both the window itself and the surrounding masonry structures.
- Thermal insulation and waterproofing: direct contact between the window and the foundation can lead to thermal bridges where heat escapes, which is undesirable in terms of preserving the building's thermal energy. Understructure, made of insulating materials like expanded polystyrene or hardened polystyrene (such as Klinaryt), creates an insulating barrier that reduces heat loss. In addition, the understructure protects against moisture penetrating from the ground, which is especially important in buildings with low elevations or in areas with high groundwater levels.
- Aesthetics and finish: Understructure allows the window to be aesthetically and technically aligned with the foundation line, creating a consistent and aesthetically appealing transition between the window and the wall. It can also help maintain the visual line of the building facade.
- Protection against mechanical damage: Placing an understructure between the window and the foundation reduces the risk of mechanical damage to the window caused by direct contact with hard concrete. Thanks to its structure, the understructure absorbs some of the shocks and impacts that could otherwise harm the window frame.
In conclusion, the use of understructure when installing windows directly on the foundation is recommended both to ensure the long-term durability and functionality of the window installation, and to improve the thermal insulation and aesthetics of the building.
