It is important to check heat losses from the shutter box because often it is not isolated and it is a significant point of air leakage. The solution consists in installing roller shutter box insulation.
It allows about 5 to 10% of energy savings depending on climate conditions
The internal space is kept, not affecting the useful surfaces
Reduce heat losses
The installation of insulation is a simple, fast and inexpensive intervention, where there is sufficient space (at least 2 cm)
The access to the roller shutter boxes may be difficult