Permanently Sealing Window Joints – Professional Tips & Step-by-Step Guide

Leaky window connections are one of the most common causes of heat and moisture damage in construction. Whether it's a new build, renovation, or simple repair – proper sealing provides long-term protection and saves heating costs. In this article, we explain what specialist companies and DIY enthusiasts need to consider.

Standards & Material Requirements

DIN 18542 regulates the sealing of external wall joints with impregnated sealing tapes. For standard-compliant window connections, pre-compressed tapes like the FAB 1500 window tape are recommended – it meets the requirements for driving rain resistance and thermal insulation in a single step.

Step-by-step instructions

1. Clean the joint area and remove old sealing material.
2. Measure the joint width – the sealing tape must be installed slightly compressed.
3. Cut the FAB 1500 window tape to the correct length and press it into the joint.
4. Seal the connection joints inside with a flexible sealant such as INSEBO HybridTec Multiflex 33.
5. Smooth the surface and allow it to cure for 24 hours.

Conclusion With the right material, a permanently tight window seal is not witchcraft – neither for the professional nor for the dedicated DIY enthusiast. All mentioned products are available directly in our shop.