4.8/5 · 328 verified reviews 10-year guarantee English-speaking team
Brussels & Wallonia Mon–Fri 9am–6pm FREN
Renov'Châssis
Aluminium sliding patio door opening onto a garden from a living room
Belgian installer · English-speaking team

Windows & doors in Saint-Gilles

Sint-Gillis

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.

4.8/5 · 328 verified reviews

  • Free measuring visit in Saint-Gilles
  • 10-year guarantee
  • CSTC-certified fitters

Get my free quote +32 472 89 59 42

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Your windows in Saint-Gilles

In Saint-Gilles, windows are part of the architecture. This dense municipality of just under 50,000 residents is home to townhouses and grand houses from the late nineteenth and early twentieth centuries, Art Nouveau façades (Victor Horta’s house and studio is here) and many large houses divided into flats. Replacing windows here takes a little more thought than elsewhere: the aim is to insulate without erasing what gives the street its character. Our team can guide you through every step in English.

Preparing your choice in Saint-Gilles

  • Is the building protected? Listing, inclusion in the heritage inventory or a protected area: your commune’s planning department (urbanisme) will tell you whether a change of appearance requires a permit.
  • Should the divisions be kept? Top lights, glazing bars and special shapes are part of the façade’s design; we take them into account when drawing the new windows.
  • Wood effect or slim aluminium? uPVC comes in colours and finishes that imitate wood; aluminium allows slim frames on the tall windows of the first-floor reception rooms (bel-étage).
  • Which glazing? Double glazing suits most rooms; triple glazing is justified on cold façades or those very exposed to noise.

Divided houses, co-ownership and rented homes

When a house has been divided, each floor may belong to a different owner while the façade stays shared. It’s simpler to agree on one model and colour, even if the floors are done one at a time. If you rent your flat, the decision is your landlord’s, and nothing should be ordered without their written agreement. For landlords – and there are many in Saint-Gilles – new windows mean more comfortable tenants and a better EPB certificate (PEB); we give you the specifications of the installed windows for the EPB assessor (see grants below).

Organising the works

Our head office in Overijse is 15 km away. During the free measuring visit, the technician takes the measurements and spots the constraints typical of Saint-Gilles streets: tricky parking, narrow staircases, tall windows that need careful handling. These go into the quote, so installation day holds no surprises, and we can go through the quote with you line by line in English. Inside, too, we plan ahead: sills, woodwork and mouldings around old openings are protected, and how the new frame meets your existing finishes is agreed with you at the visit.

Why choose Renov'Châssis

The quality of a Belgian manufacturer, the flexibility of a local craftsman

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.

Renov'Châssis fitters installing a new window on site

Installed by CSTC-certified fitters

In-house or certified partner fitters • Adjusted to the millimetre • 10-year guarantee

Direct prices

Save on your renovation by cutting out the middlemen. A transparent quote, line by line.

No reseller margin

Your project, in English

Belgian building rules, listed façades, co-ownership approvals: we explain everything clearly in English, by phone, by email or on site.

English-speaking advisors

EPB certificate

High thermal-performance windows, supplied with the technical data you need for your EPB (PEB) energy certificate.

Technical file supplied

Thermal & acoustic insulation

HR++ double or triple glazing: instant comfort and lower heating bills from the very first winter.

Double or triple glazing

Honest & thorough

A relationship built on trust and transparency

Expert advice, without the jargon

We look at your needs and point you honestly to the right windows for your budget: uPVC, aluminium or wood.

Measurements to the millimetre

A careful, free measuring visit at your home, so there are no surprises on installation day.

Careful installation by CSTC-certified fitters

Respect for your home, protected floors, airtight sealing and a clean site when we leave.

A Renov'Châssis advisor reviewing a client's project plans

A tailored study of your project

We review your plans and existing quotes to offer you the best performance at a fair price.

4.8/5 · 328 verified reviews
A clear, stress-free process

Your new windows in 5 simple steps

We handle everything, from your first quote to after-sales service.

  1. 1

    Free quote within 24h

    Describe your project online and receive your priced offer within 24 hours, with no obligation.

  2. 2

    Measuring visit

    A technician comes to your home to take exact measurements, free of charge.

  3. 3

    Made to measure

    Your windows are manufactured to the exact dimensions taken at your home.

  4. 4

    Careful installation

    Our qualified fitters install everything precisely and leave your home clean.

  5. 5

    10-year guarantee & after-sales

    We remain available after installation for any question, in English or in French.

Not sure about measurements or building rules?

Our advisors will guide you by phone, free of charge, in English.

+32 472 89 59 42
Recent projects in Belgium

Verified reviews & projects

See how our clients in Brussels, Namur and Liège added value to their homes while cutting their energy use.

4.8 / 5

Based on 328 verified reviews (translated from French)

uPVC windows installed by Renov'Châssis 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!”
ML

Mark L.

Homeowner

Aluminium glazed opening installed by Renov'Châssis Namur Aluminium windows
“A very good company, responsive and professional. The aluminium windows are beautiful and the difference in thermal insulation is impressive.”
VL

Virginie L.

Homeowner

uPVC windows installed by Renov'Châssis 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.”
KB

Kenza B.

Professional client

We also work near you

Renolution grants and the EPB certificate in Brussels

Brussels' Renolution grants are currently suspended: no application can be submitted for final invoices dated 2025 or 2026, and the Region has not yet decided on a new form of support. Updates are published on renolution.brussels.

The Ecoreno loan can pre-finance renovation work, and Homegrade offers free advice to Brussels residents. Efficient windows generally improve the home's EPB (PEB) certificate, required when you sell or let a property: we provide you with their technical specifications.

Information checked on 17 October 2026.

Frequently asked questions

My house still has its original wooden windows: do they have to be replaced?

Not necessarily. Old windows in good condition can sometimes be restored by a specialist joiner, which is often preferable on a remarkable façade. If the wood is damaged or you want much better insulation, we offer new uPVC or aluminium windows designed to respect the façade.

Is uPVC allowed on a maison de maître façade?

It depends on the building's status and on how the new window looks. For a protected property, only Saint-Gilles' planning department (urbanisme) can answer; we provide the frame sections and colours to submit to them. On an unprotected house, well-designed wood-effect uPVC usually fits in without difficulty.

Can you work in a street where parking is difficult?

Yes. The technician checks access conditions during the visit, and we organise delivery and installation accordingly. If a temporary parking permit is needed, we explain how to apply for it at the municipality.

Your window project in Saint-Gilles

Free quote within 24 hours, then a technician comes to measure up at your home, free of charge. We explain everything in English.

Request a free quote +32 472 89 59 42

Free quote in 24h