Roof windows in Auderghem
We install and replace roof windows in Auderghem and the neighbouring communes. Whether it's a standard Velux on a converted attic, a dome on a flat roof, or the replacement of an existing window that's starting to let water in, this is work that touches both the covering and the waterproofing. For owners who want to bring natural light into a space under the roof, it's often the most effective intervention.
What does this work involve
Fitting a roof window isn't just cutting a hole and screwing in a frame. The waterproof junction between the window and the existing covering is the critical part: if that junction is done badly, water finds a way — not always immediately visible, often into the structure before the stain appears on the ceiling.
We work on several types of openings: classic roof windows (Velux type or equivalent), top-hung, centre-pivot or fixed depending on use and roof pitch; roof domes, mainly on flat or gently sloped roofs, bringing zenithal light into spaces where a classic window isn't possible; and the replacement of existing roof windows, when a 20- or 30-year-old window starts to swell, let in the cold or leak at the frame.
When should you act
A few common situations:
- Your roof window leaks at the junction with the roof after rain
- The frame is swollen, deformed or no longer closes properly
- Excessive condensation appears inside the glazing (worn double glazing)
- You want to convert the attic and bring in light
- Your flat roof lacks natural light and you want to fit a dome
Why it happens
Leaks around roof windows almost always come from the waterproof junction, not the window itself. Over time, the lead or zinc surrounds framing the window tire, crack or come loose. Frost makes it worse: water seeping into a micro-gap expands and opens the way faster.
On the houses of Auderghem built in the 1970s-1980s, we still find single-glazed timber frames. They insulate poorly, handle moisture badly and end up letting water through. Replacing them with a PVC or aluminium frame with double glazing genuinely changes comfort and energy use.
What makes the price vary
The price depends on the type of opening: a standard roof window costs less than a made-to-measure dome. The size of the window counts. So does the type of existing covering: working on natural slate takes more care than on a tiled roof.
The state of the current junction plays a part: if the structure around it has taken on moisture, it sometimes needs work before the new window goes in. And if you want several windows in the same area, the travel is shared.
Repair or replace
If your roof window only leaks at the junction and the frame is still in good condition, we can redo the waterproofing without changing everything. It's cheaper and just as effective if the window itself still has a few good years left.
If the frame is damaged, the glazing broken or the window too old to find parts for, a complete replacement makes more sense. We tell you what we see without steering you towards the most expensive option.
See also: Dormers · Roof insulation · Roof structure & carpentry
Frequently asked questions
Does fitting a roof window require a permit in Auderghem?
For the simple like-for-like replacement of an existing window, generally not. For creating a new opening, check with the commune. We can advise you on this, but the administrative step remains yours.
What's the difference between a Velux and a generic roof window?
Velux is a brand that gave its name to the product, like Hoover for vacuum cleaners. Other manufacturers of comparable quality exist. We work with different brands depending on needs and budget.
Does a roof dome suit every flat roof?
Most of them, yes. The size and type of dome adapt to the thickness of the roof and the intended use. We check feasibility before starting.
How long does fitting a roof window take?
For a standard replacement, often half a day. For a new opening with structural modification, count one to two days.
Is your work guaranteed?
Yes, a 10-year workmanship guarantee. The manufacturer's warranty on the window itself comes on top.