To buy uPVC windows online, you build each window in a configurator: choose the profile system, glazing and colour, enter the sizes and the price appears straight away. The risk sits in the details you supply yourself: the frame size, which way each sash opens and how the window will be fitted. Below are the mistakes we see most often when we check enquiries, and how to avoid them.
How do you buy uPVC windows online with us?
There are five stages. You put your windows together in the window configurator and see the price after every change. Within 3 working days a person prepares your quote, including delivery. Before production you approve a drawing and specification of every window. Then you pay 100 % and production takes 3–8 weeks. Finally the windows arrive on stillages at your address. We do not offer fitting: you install them yourself or with a fitter you choose.
We have been in the window trade since 1997 and have completed more than 5,000 orders. On every quote we check the sizes, opening sides and item descriptions, and most of the corrections we suggest come down to a handful of recurring mistakes.
Mistake 1: entering the opening size instead of the frame size
The configurator asks for the frame size, not the size of the hole in the wall. The frame has to be smaller than the opening by a fitting gap that takes packers, foam and sealing tapes. Measure the opening in three places (top, middle, bottom), take the smallest figure and deduct the gap from that. How big the gap should be depends on the wall and the fitting method, so agree it with your fitter. If in doubt, send us the raw measurements and photos of the opening through the contact page and we will check them with you.
Mistake 2: describing the opening side from outside
Left and right mean different things in the garden and in the room. Always describe the opening side of each sash as seen from inside. It is one of the most common discrepancies we find in enquiries. Check the handle and hinges of every window again on the drawing you approve.
Mistake 3: choosing the fitting method after ordering
Windows can go into the reveal of the opening, against the inner face of the wall, or over an old frame that stays in place. The method decides the type of frame and its size. For fitting over an existing frame without breaking out plaster, the configurator offers a renovation frame. Whether it is available depends on the system, so check before you compare prices. Agree the fitting method with your installer first, then enter the sizes.
Mistake 4: adding a roller shutter at the end
A top-mounted roller shutter box sits on the window and increases its overall height. If you add shutters after measuring and entering the windows alone, the set will not fit the opening. Decide on roller shutters at the start and select them in the configurator straight away. The Aluprof shutters on offer are top-mounted, face-fixed and concealed, with manual, wired or Somfy io radio operation.
Mistake 5: a sash too narrow or a door too tall
An opening sash must be at least 450 mm wide. Two sashes will not fit a narrow window, so use one opening sash and a fixed pane instead. A door leaf can be no more than 2300 mm high; a taller opening gets a fanlight above the door. The configurator enforces these limits and suggests a solution.
Mistake 6: a colour combination that cannot be ordered
For uPVC windows you choose a colour outside with white inside, or the same colour on both sides. We do not make two different colours on the two faces, nor colour on the inside only. One colour applies to the whole order, and white is included in the base price. More on foils and palettes in our article on window colours.
Mistake 7: comparing the window price alone
The configurator price covers the windows. Delivery is charged per stillage space according to the destination country and is stated in the quote before you order. Unloading is your responsibility: a forklift or 2–3 people. Prices include VAT, and for delivery to another EU country the VAT of that country applies, which we account for under the OSS scheme. You see the rate and amount in the quote. This is general information, not tax advice. When comparing offers, add up the full package: windows, delivery, unloading and the fitter's bill. What drives the price is explained in how much windows cost without fitting.
Mistake 8: counting on a 14-day cooling-off period
Made-to-measure windows are produced to your specification. Across the EU the 14-day right of withdrawal does not apply to them (Directive 2011/83/EU, Article 16(c)). That is why you approve a drawing before production, and why sizes are locked once you have paid. Read the drawing line by line: size, layout, opening, glazing, colour.
Mistake 9: no plan for delivery day
The windows arrive on stillages, and large units can weigh over 100 kg. Arrange access for the lorry, people to unload and a dry, covered place. Store the windows upright, away from sun and damp, and remove the protective film no later than 4 weeks after delivery. Book your fitter for a date after delivery. The windows come with a declaration of performance and CE documents, and the GALI warranty runs for 2 years.
Once your list is ready
Start with one window in the uPVC window configurator and add the rest. You can price the same project in several systems, such as Kömmerling, VEKA or Salamander, and compare on your own sizes. We deliver regularly to Germany, Belgium, the Netherlands, France, Austria and Czechia; see export for details. If you have a window schedule from your architect, send it via contact and we will quote from it.