How To Measure for New or Replacement Windows: The Dale Joinery Guide

Measure your windows correctly with Dale Joinery’s guide on how to measure new or replacement windows!

If it’s finally time to replace your windows and opt for something energy-efficient, or you’re in the process of building your own home, you’re going to need to measure your windows correctly. Most companies offer a free consultation visit to measure your windows before supplying and installing them. However, if you’re ordering them online to save costs, you’re going to need to know how to take accurate measurements. Survey costs will generally be included within the price (not always visible).

If you’re looking for a door measurement guide, head on over to our ‘how to measure for new or replacement doors’ guide.

How To Measure For New or Replacement Windows

When measuring windows, it’s essential that you measure from the outside opening. This essentially refers to the brickwork opening. There are two sets of measurements you need to take when measuring windows: the height and the width.

Ensure you take the measurements in millimetres, not inches. This is because it allows you to measure more accurately, especially when your chosen manufacturer converts your measurements to metric. Where you measure from will be determined by the external finish of the building. Standard (flush reveal) Brickwork or facing stone is the easiest as you can generally see the entirety of the frame you are measuring. Houses that have either a rendered or cladded external finish will need some of the internal plaster or external render/cladding removed to obtain a true measurement as both the internal and external finishes cover the window frame.

 When measuring sash windows (especially period properties) you will need to measure internally as box sash windows are fitted in Check reveal, which means the external aperture is smaller than the internal and the windows have been fitted from the inside (up against the external wall leaf).

From a Dale point of view, If all you require is a quotation the best option is to either provide us with approximate measurements (subject to a final survey), send us a photograph of each elevation and we can use our measurement software to provide you with approximate dimensions or call us and we will come to you and take care of everything.

What You'll Need For Measuring

Tape measure.

Something to write down the measurements, e.g. a piece of paper or your phone.

Measuring the window height:

You’ll need to measure the left, middle, and right sides to calculate the height.

Once measured, identify the shortest measurement and deduct it by 10mm.

Once you’ve deducted it by 10mm, the final measurement determines the height of your window.

The reason you deduct 10mm is so it allows a small fitting allowance around your new frame. Your chosen window installer will be able to ensure the new window sits properly when it’s in place. If there are any gaps, they are usually fitted with spacers and filled in.

Measuring the window width:

Repeat the steps above and note down your measurements to measure the window width.

That’s it! Once you have the height and width measurements, you can start to look at replacing your windows. If you are considering replacing your windows and you’re still in the beginning stages of deciding what style you want, what glazing options are available, and what material is best, be sure to check out our guide to selecting windows.

Although there are many options to choose from, from uPVC and aluminium, we highly recommend timber windows. Thanks to their natural insulation, aesthetic appeal and extremely long lifespan, you can reduce energy bills and add value to your home.

About Dale Joinery

At Dale Joinery, we pride ourselves in creating the ultimate timber window and door for you. We carefully source all parts of our frame and only use the best materials to guarantee product security, quality and longevity. If you’re interested in our sustainable timber windows and doors for your project, please get in touch or give us a call on 0800 030 2222. Download our digital brochure or request your physical brochure online for more inspiration.