How to Measure Windows: uPVC Windows Measuring Guide

Many individuals want to know how to made to measure upvc windows. Many individuals struggle with this question, so we’ve put together this guide to help! If you’re considering getting replacement uPVC windows, you’ll need to know how to measure the size of the window you’ll need. That and more will be demonstrated in this post.

To begin, resist the need to measure merely the existing frame. You should measure from the brickwork rather than the window frame. Otherwise, you’ll end up with erroneous measurements and a window that doesn’t fit properly.


It’s also worth mentioning that certain window businesses won’t be able to simply take your dimensions and make a window that fits exactly. Different firms make different allowances, and some don’t make any at all, so it’s always a good idea to have the window installation company take their measurements. The following information is intended to serve as a rough guide to obtaining an accurate measurement and obtaining costs for your new windows.

Let’s get the technical stuff out of the way and talk about measuring for new windows.

How to measure for new uPVC windows

Measure window width

Using a tape measure or a ruler, determine the width of your window. The measurement must be taken from the outside in. You’ll also want to consider any overhanging (most likely on the front fa├žade), as these will restrict the amount of space available inside the entrance.

Measure window height

Next, determine the height of your current window in centimeters or inches. It makes no difference whether the frame is internal or external; just make sure they’re both measured using your tape measure/ruler!

Measure from the brickwork opening once again.

Measuring window openings

Simply measure the width of an opening at the top, center, and bottom to determine the size of the windows.

Now you must determine the narrowest measurement and subtract 10mm from it. The breadth is then determined by this figure.

Measure the height of an opening on the left, center, and right to get the height. As before, take the least measurement and subtract 10mm to determine your height.

Each window opening will require the same processes to be completed.

Sounding a little complicated?

It’s critical to have the measurements of your replacement windows correct. The last thing you want is to spend hundreds of pounds on a new window that doesn’t fit.

Take a look at our conventional window sizes chart for some guidance on how small or huge windows are typical.

To be safe, we always recommend getting a pro window installer to measure up for your replacement windows before placing an order. If you still want an estimate, our online window designer will let you enter exact measurements, ballpark measurements, or utilize our standard window sizes to get an estimate.

You may then ask for such a window fitter to come out now and formalize the quote and give you a final figure, ensuring that get everything just right after you’ve received a window quote and assessed whether you’re content with the reference price.