Wooden windows listed buildings must be preserved

The preservation order stipulates strict rules when old wooden windows are located in and around a building. Basically, the preservation of old substance is preferable to the reconstruction. If components have to be replaced, technical considerations such as the moisture balance of the building must be taken into account in addition to visual criteria.

Receipt despite Energy Saving Ordinance

In nearly all buildings, whose construction and equipment with wooden windows took place before the Second World War, grab regulations from the monument protection. When windows are modernized, the thermal insulation and associated U-value of the wooden windows is usually the deciding factor.

Windows in old buildings such as in a half-timbered house often no longer meet the current energy standards, as required by the European Energy Saving Ordinance (EnEV). Often a window repair taking into account the conservation of historical monuments is a complicated, lengthy and expensive affair.

Wooden windows listed buildings must be preserved: listed

Components and inventory

In general, replacement of the wooden windows is only allowed if all other conservation measures have been excluded. The monument protection for windows defines three component groups:

  • glazing
  • window frame
  • Bauverbund or building connection

After a thorough, detailed and written inventory, the required work steps for each individual window must be planned, justified and approved.

Renew glazing

If the frames are well-preserved and have a reliable load-bearing capacity, replacement of the glazing can be considered. Retrofitting to the soundproof window can be done by two-layer insulating glass.

However, this type of restoration is controversial and can not always be approved. Even though the advantages of insulating glass are an increased soundproofing and the improvement of the U-value of old windows, the necessary intervention in the frame construction is often not tolerable.

linseed oil paint

Another important aspect in the protection of monuments is the regulation to determine the type of wood of the windows and to bring about, as until the 1950s exclusively used, return to the painting with linseed oil paints.

Tips & Tricks

As a general rule, you must maintain your listed wooden windows in the highest possible original fidelity. This also applies to the number of sashes, closing direction and opening function.

Video Board: Opening up an historic timber frame - many problems..