Made-to-measure uPVC, aluminium and wood windows with high thermal performance, sold without middlemen and installed under a 10-year guarantee. And our team speaks English, from the first call to the final check.
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Braine-l’Alleud is three places in one: a lively town centre, residential areas that have spread over the decades, and villages that have kept a more rural feel, such as Ophain-Bois-Seigneur-Isaac and Lillois-Witterzée. So the windows due for replacement come from every era – original single glazing in older houses, tired early double glazing in post-war homes, wooden frames that no longer shut properly. Before talking models, it helps to know what you want from your new windows, and we’re happy to talk it through in English.
Where are you losing heat? Draughts around the opening sashes, condensation on the panes or a room that is always cold point towards better glazing and a more airtight installation. Triple glazing is mainly justified on façades facing north or the prevailing winds; elsewhere, good double glazing is often enough.
Which material for your façade? uPVC insulates well and needs little maintenance. Aluminium allows slimmer frames and large glazed areas, popular for opening a living room onto the garden. Both come in many colours, including finishes that go well with brick or render.
Do you have to replace everything at once? Not necessarily. Some owners start with the living areas or the front door and do the rest later. We’re happy to price both options so you can compare.
All our windows are CE-certified and installed with a 10-year guarantee.
One last point that is often overlooked in Braine-l’Alleud: shutters and insect screens. If you plan to fit them one day, mention it at the visit, as it can influence the choice of frame and the way the window is set into the opening.
Our head office in Overijse is 16 km from Braine-l’Alleud, with direct access to the Ring. We also cover the neighbouring municipalities, from Waterloo to Genappe by way of Lasne, Ittre and Braine-le-Château. A technician visits to take the exact measurements of each opening and note the condition of the sills and masonry. Your quote is based on that visit, never on a guess from a distance, and we can explain every line of it in English.
Replacing windows is one of the works that improve a home’s PEB certificate. For grants in Wallonia, see the section below: we provide any technical documents you need, but can’t guarantee an amount.
No middleman margins: you deal directly with the team that designs, adjusts and oversees the installation of your windows and doors, right down to the finishing touches.
Save on your renovation by cutting out the middlemen. A transparent quote, line by line.
No reseller margin
Belgian building rules, listed façades, co-ownership approvals: we explain everything clearly in English, by phone, by email or on site.
English-speaking advisors
High thermal-performance windows, supplied with the technical data you need for your EPB (PEB) energy certificate.
Technical file supplied
HR++ double or triple glazing: instant comfort and lower heating bills from the very first winter.
Double or triple glazing
We look at your needs and point you honestly to the right windows for your budget: uPVC, aluminium or wood.
A careful, free measuring visit at your home, so there are no surprises on installation day.
Respect for your home, protected floors, airtight sealing and a clean site when we leave.
We handle everything, from your first quote to after-sales service.
Describe your project online and receive your priced offer within 24 hours, with no obligation.
A technician comes to your home to take exact measurements, free of charge.
Your windows are manufactured to the exact dimensions taken at your home.
Our qualified fitters install everything precisely and leave your home clean.
We remain available after installation for any question, in English or in French.
Our advisors will guide you by phone, free of charge, in English.
See how our clients in Brussels, Namur and Liège added value to their homes while cutting their energy use.
Brussels
6 uPVC windows + door
“I had 6 uPVC windows and a front door installed. The result is excellent, and the installation was done in a single day, just as André promised. No more draughts at all!”
Mark L.
Homeowner
Namur
Aluminium windows
“A very good company, responsive and professional. The aluminium windows are beautiful and the difference in thermal insulation is impressive.”
Virginie L.
Homeowner
Liège
Full renovation
“I recommend Renov'Châssis to all my clients. The quality of the products and the reliability of the team are faultless. A partner you can trust.”
Kenza B.
Professional client
Wallonia's temporary 2025-2026 home renovation grant scheme has closed: applications, including the final invoice, had to be submitted by 30 September 2026 at the latest. Among other things, it required a home energy audit before the works and windows with an average Uw value of no more than 1.50 W/m²K. So far, the Walloon Region has not announced a new scheme for windows; official information is published on wallonie.be (in French).
To finance the work, ask about zero-interest loans from the SWCS or the Fonds du Logement de Wallonie. Whatever the grants, efficient windows generally improve the home's PEB energy certificate, which is required to sell or let a property: we provide you with their technical specifications.
Information checked on 17 October 2026.
It improves insulation mainly on façades that get little sun or are very exposed. On a well-oriented façade, efficient double glazing is often a better compromise. The technician advises you room by room during the visit.
Yes, we work in all three districts of the municipality (postcodes 1420, 1421 and 1428) on the same terms. The measuring visit takes place at your home, whichever village you live in.
Yes. A front door can be replaced on its own, in uPVC or aluminium, and matched to the windows later. We check that colours will match if you plan to change the windows afterwards.
Free quote within 24 hours, then a technician comes to measure up at your home, free of charge. We explain everything in English.
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