A new plan from the provinces of Utrecht and Overijssel should drastically reduce illegal isolation without checking for bats or other animal species, the AD writes.
It is a legal obligation to investigate whether animals are present between the walls before insulating a cavity wall. Yet homeowners hardly do. Usually because they are not aware of the obligation, sometimes because it is too expensive: such an investigation quickly costs between 3500 and 4000 euros.
Some protected bird and bat species like to stay in cavity walls and roofs, but are suffocated or chased away when insulating a home. Nature-friendly insulation companies are also active, which lure the animals outside before isolating them and then offer them a new home with special nesting boxes and bat boxes on the wall. This method is only used on a small scale.
A new design of the isolation studies of the provinces of Utrecht and Overijssel should therefore better protect the animals under roofs and in cavity walls. Instead of an individual investigation, municipalities will have a wall investigation carried out in an entire district.
The frequency of illegal isolation is unknown. Tijs de Bree, deputy of the province of Overijssel, thinks it happens frequently. “We know that plenty of houses are being insulated, but we rarely receive the request to grant the correct permit or removal for this. Then you know that unfortunately it is often not done in the right way,” he says in the NOS Radio 1 Journaal. .
Some insulation companies look into the wall with a camera before they get started, but the animals are not always visible on it, with the result that bats, sparrows and swifts die through the insulation material.
The provinces are asking residents, municipalities and insulation companies to work together and save as many birds and bats as possible from isolation death. Companies are asked to follow training courses and municipalities are drawing up a plan to allow the protected animals to return.
For residents, this mainly concerns a contribution to the extra costs, which can amount to about 300 to 500 euros on top of the insulation price of between 1,500 and 2,000 euros. According to De Bree, that is indeed a considerable amount, “but a lot cheaper than it should be”, referring to the expensive individual research.
However, not all bats benefit from this solution. René Janssen of the Foundation for Ecological Bat Research in the Netherlands is particularly concerned about bat species that are too large to use the bat boxes.
In the AD, he proposes to leave these species alone and to compensate the residents of the house for their high energy bills: “It concerns an average of seven homes per city, that is quite possible. And you save those colonies: if one is gone it’s gone forever.”