The roof is the first place to invest in when insulating your home : a poorly insulated roof will cost you up to 30% in heat loss in a semi-detached building.
Insulating a roof is not very expensive and the investment is quickly recouped. In addition, the Brussels Region offers insulation grants.
Prices vary depending on the layout of your roof and the chosen insulation materials. There are a wide number of options: minerals (rock and glass wool), synthetic materials (expanded or extruded polystyrene, polyurethane, etc.) or natural (wood wool, hemp, cellulose, cork, etc.). Thin multilayer insulators are controversial.
For general reference purposes, below is the expected price range, installation included. Please note: these do not include the additional work:
Something to keep in mind
Insulating the attic floor (not habitable attic) instead of the roof is at least two times cheaper: smaller underside surface, little to no finish required, quick and simple installation.
Whether from the inside or outside, insulating a roof involves additional work:
Energy grants are revised each year on January 1st. Visit the Brussels Environment website to find out the applicable grant award conditions.
Invoices dated up to 31 December may be sent in to Brussels Environment after the start of the following year (see detailed regulations for each grant).
A poorly insulated roof causes up to 30% heat loss in a semi-detached building. The average household in Brussels spends € 1,600 per year on energy, of which 60% for heating, i.e. € 960.
Which means that insulating your roof can reduce your gas bill from € 960 to € 672. That is a gain of at least € 288 per year.
Let us run a simulation:
100 x 22 = € 2,200
100 x 25 = € 2,500
Total: € 4700 excluding VAT
+ 6% VAT: € 282
|100 x 30 = € 3,000|
Annual savings made on
|7 years maximum|
This estimation can be greatly shortened if:
Before embarking on this work yourself, consider the following:
If in doubt, also remember that the DIY savings are rather small.
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