Requirements of the perimeter joint
In accordance with the specifications of ÖNORM B5320 and the RAL guidelines for the installation of windows and front doors, these requirements are divided into 3 levels.
- On the outside, protection against driving rain and UV exposure
- In the middle, thermal and sound insulation
- In the room, an all-round airtight seal
A needs-based joint seal is selected from a range of coordinated products for the construction project. Depending on the building, the connection and the installation conditions, different products can be used. In most cases, this involves a three-stage construction of the window perimeter joint.
1. Weather protection level
It must be windproof and driving rain-proof, but open to vapour diffusion.
2. Functional level
This lies between the outer and inner seal and serves as sound and heat insulation in the connection area. It must be executed circumferentially and be as free of cavities as possible.
3. Room level
Air tightness must be created at this level. This seal must have a higher Sd value than the seal on the outside.
Outside: Rain, wind, sound, UV exposure.
Room: Heating energy, room humidity
Building: Building movement, tolerances
Windows: Length change, dead weight
Use: Force transmission, impact load
All these requirements must be balanced in the perimeter joint. The perfect useability of windows entirely depends on the perimeter joint. The applicable technical data sheets must be observed during application.
