We upgrade existing box-type windows through targeted modernization measures:

✅ Improvement of airtightness
✅ Optimization of thermal insulation
✅ Overhaul of fittings and functionality
✅ Addition of modern sealing systems
✅ Timber repairs and surface treatment

Professional renovation increases comfort, reduces energy losses, and at the same time preserves the historic building fabric.

Stop drafts – efficiently seal windows in older buildings

Leaky windows are one of the most common causes of heat loss in older buildings. In many cases, professional sealing alone is sufficient to significantly reduce heating costs and drafts.

Our window sealing service includes:

✅ Milling in modern overlap seals
✅ Adjustment and overhaul of fittings
✅ Optimization of locking points
✅ Sealing of glazing rebate and sash
✅ Functional inspection and fine adjustment

The result: noticeably greater living comfort with minimal intervention in the existing window structure.

Window upgrading in harmony with heritage conservation

In listed buildings, preserving the original fabric is the top priority. Complete window replacement is often not permitted or not desired.

We renovate historic windows in compliance with heritage conservation requirements:

✅ Preservation of existing frames and profiles
✅ Energy performance improvement without altering the appearance
✅ Reversible renovation solutions
✅ Repair instead of replacement
✅ Sustainable, CO₂-reduced modernization

This ensures that the architecture, character, and value of the property are maintained.

Modernizing the energy performance of historic windows

Even older wooden windows can be upgraded to modern energy standards. With new thermal insulation glazing, additional seals, and optimized fittings, heat loss is significantly reduced.

Typical measures:

✅ Thermal insulation glass up to Ug 0.7 W/m²K
✅ Additional sealing levels
✅ Bonding of the glazing rebate
✅ Optimization of functionality and airtightness
✅ Upgrade to RC2 possible

The windows are preserved — energy consumption and CO₂ emissions decrease.