Roof insulation
in Wavre
On the building stock of Wavre — brick terraced houses in the centre, detached villas on the outskirts, plenty of concrete-tile roofs laid in the 1970s — roof insulation needs a method that fits. Roof insulation of the loft, the loft floor and the roof slopes, with a continuous vapour barrier and ventilation kept clear.
The context in Wavre
Why here in particular
The valley floor stays damp much of the year: the north-facing slopes green over with moss faster than elsewhere and the bottom of facades marks. So we adapt the kit and the method rather than running a standard protocol.
In Belgium, 25 to 30 % of the heat lost from an uninsulated house goes out through the roof. But roof insulation fitted without a continuous vapour barrier and without an air gap simply moves the problem: the vapour condenses in the wool and the roof timbers take in water.
- Quote
- Priced after a site visit, free of charge and with no obligation.
- Duration
- 1 to 4 days depending on the surface area and the layout.
- Call-out
- Included in Wavre and neighbouring municipalities
How it runs
How the job runs
The same protocol everywhere, adapted to what the visit reveals on site. Nothing is decided from the pavement.
- Survey and calculation of the thicknesses
- Mineral wool or cellulose insulation
- Continuous vapour barrier and tapes
- Treatment of penetrations and openings
- Keeping the air gap
- Removal of offcuts
Site assessment
Available thicknesses, roofing underlay present or not, existing ventilation.
Preliminary treatment
Sound roof timbers before insulating. We never cover over attacked timber.
Fitting the insulation
Mineral wool between and under the rafters, or blown onto the loft floor.
Vapour barrier
Continuous membrane, overlapping strips, tape on every penetration.
Ventilation
Air gap kept under roof covering. That is what prevents condensation.
Frequently asked questions
Roof insulation in Wavre
The questions we get asked most often before this kind of job.
Do you lose ceiling height?
On a pitched slope yes, a few centimetres. We measure it beforehand so you can decide knowing the facts.
What thickness should you aim for?
For a roof slope, 22 to 30 cm in total depending on the product’s lambda. Below that, the gain does not pay for itself.
Loft floor or roof pitch?
If the loft is not lived in, insulating the floor costs less and heats less volume. If it is converted, it is the roof pitch.
Do you come out to Wavre with no extra call-out charge?
Yes. Wavre is one of our 17 municipalities: the call-out is included in the quote, not added at the bottom of the invoice.
Other work in Wavre
While we are on site
Combining two jobs in one visit brings the invoice down. We suggest it when it makes sense, never to pad the quote.
Roof insulation in the neighbouring municipalities
Your job in Wavre
On-site visit, detailed costing within 48 working hours, with no obligation on your part.