Information on making a proper

connection joint using selants

Requirements on the connection joint

According to the specifications of ÖNORM B5320 and the RAL guideline about the proper installation of windows and front doors, these requirements are split to three tiers.

  • Protection against driving rain and UV impact for outer joints
  • Heat and sound insulation in between
  • Air-tight finish all around for joints in the room

From among a number of coordinated products the right joint sealing based on the needs is chosen for the building project. Different products can be employed, depending on the building, the connection situation and installation conditions. In most cases the window connection joint will be designed following a three-tier system.

1. WEATHER PROTECTION TIER
It must be windtight and watertight under driving rain but open to vapour diffusion.

2. FUNCTIONAL TIER
This level is situated between the outer and the inner sealing and serves the purpose of sound and heat insulation in the area of the connection. It must run around the whole circumference and must be as free of voids as possible.

3. ROOM-SIDED TIER
This is where air-tightness has to be established. The SD-value of this
sealing must be higher than the one on the outside.

Outside: rain, wind, sound, UV impact
Room side: heating energy, room humidity
Building: structural movements, tolerances
Windows: changes in length, own weight
Use: dissipation of forces, impact load

All these requirements must be equalised in the connection joint. The proper use of windows absolutely depends on the connection joint. For application, the relevant technical data sheets shall be observed.