Historic change for exterior insulation law

PLANS to force property owners to fit exterior insulation if they are carrying out work on a building’s facade have been changed after complaints from owners of historic properties.

Now properties built before 1948 and using materials such as cob (clay and straw), wood or plaster will be exempt from the obligation, which would have applied from January 2017.

The law, issued in May this year, was aimed to improve energy efficiency by forcing owners to cut heat loss through walls – with 35% of energy wasted as heat lost through the walls of uninsulated houses.

However, despite exemptions for historic properties it was feared colombage buildings, those in red-brick and others in dressed stone would be altered and covered up by unscrupulous builders.

Environment Minister Ségo­lène Royal agreed the change after meeting G8 Patrimoine, a group of historic building preservation societies. A new decree will clarify the exemptions.

Owners of homes outside the scope of the exemptions must upgrade their property’s energy efficiency by fitting extra insulation at the same time as any major work on roof or facade.

The property’s energy rating will be improved and, possibly, the resale value but as walls can often only be insulated by adding a layer on the outside, the law already exempts projects where the cost-benefit cut-off point exceeds 10 years.

Pre-1974 houses will not have insulation unless retro-fitted.