uPVC windows buying guide in brief: choose a profile 76–88 mm deep, glazing that suits the house, a colour from the brand's range and a frame that matches the installation method, either standard or a renovation frame over the old one. For a new, energy-efficient house, take an 82–88 mm profile with a central seal (MD) and triple glazing. In French-speaking Belgium these windows are called "châssis PVC". You see the price of every version straight away in the configurator; below are five decisions and a checklist before you order.
uPVC windows buying guide: five decisions
1. Profile
The uPVC profiles we offer are 76–88 mm deep and come from four German brands: VEKA, Kömmerling, Salamander and Gealan. AD versions have two seals, MD versions a third, central one. Such a profile resists wind and driving rain better and reduces noise. The lowest whole-window Uw comes from Kömmerling 88 MD (from 0.73 W/(m²K)), just ahead of Salamander bluEvolution 82 (from 0.75). When replacing windows in an older house, a 76 mm profile is often enough. If a cheaper system will do the job, we will say so.
2. Glazing
You choose double or triple glazing with a warm edge spacer. Some systems take only one of them, and the configurator shows this when you choose. Safety, acoustic and solar control glass is available in systems with triple glazing. Obscure glass, for a bathroom for example, can be chosen for a single window. More in our article on double and triple glazing.
3. Opening type and layout
A fixed window is the cheapest, and every extra sash adds to the price. Tilt and turn is the standard. An opening sash must be at least 450 mm wide, so in a narrow window one sash and a fixed pane work better. A door leaf can be at most 2300 mm high; a taller opening gets a fanlight. For the patio there are tilt and slide (PSK) and lift and slide (HST) doors.
4. Colour
White is included in the base price. Foils (anthracites, greys, matt black, woodgrain) are ordered on the outside with a white inside, or in the same colour on both sides. We do not make two different colours on one window, and the whole order has one colour. Details are in our article on window colours.
5. Frame and installation method
A standard frame suits normal installation in the opening (in French, pose en applique or en tunnel). A renovation frame sits over the old frame, without breaking out the plaster: that is pose en rénovation. There is also a Dutch-style frame, with or without a fin. Frame availability depends on the system, so check it in the configurator before you decide.
If uPVC is not enough because you are planning floor-to-ceiling glazing or a specific RAL colour, read our uPVC and aluminium comparison.
What to order with the windows?
- Aluprof external roller shutters: top-mounted (the box adds to the window height), facade-mounted or concealed. Manual, wired (your electrician connects the cable; we do not sell switches) or Somfy io radio control.
- Frame and roller fly screens, for opening sashes.
- Aluminium external sills.
- Fitting materials: the configurator suggests foam, tapes, anchors and wedges.
Checklist before ordering uPVC windows
1. Measure each opening in three places and note the smallest size. Give the frame size, not the opening size, and if in doubt send photos and the raw opening sizes. 2. Describe the opening side as seen from inside. 3. Decide on a top-mounted shutter now, because it changes the window height. 4. Check that each opening sash is at least 450 mm wide. 5. Choose one colour for the whole order. 6. Make sure the chosen system has the frame you need (standard or renovation). 7. If you are counting on a Walloon or Brussels grant, check the conditions on the region's official website. Grants often require installation by a company. 8. Arrange people for unloading (a forklift or 2–3 people) and a fitter for the delivery date. 9. Check the drawing and specification you approve item by item. Made-to-measure windows are exempt from the 14-day right of withdrawal (Directive 2011/83/EU, Article 16(c)).
We built this list from what we check with every quote. We have worked with windows since 1997, have completed more than 5,000 orders and have exported windows since the late 1990s. Most corrections still concern the same things: the opening size instead of the frame size, the opening side described from outside, and a top-mounted shutter chosen too late.
Price your uPVC windows
Build your windows in the window configurator and see the price straight away, after every change. We describe our uPVC systems on the uPVC windows page and deliveries to Belgium and France on the export page. We prepare a quote including delivery within 3 working days, production takes 3–8 weeks from payment, and you arrange installation yourself or with a fitter of your choice.