Shutters
How to Measure for Shutters (All Window Types)
If you’re looking into shutters, you might assume measuring a window is fairly straightforward. All you need to do is measure width and height, and that’s job done. Unfortunately, shutters aren’t quite that simple.
Unlike a blind, where being a few millimetres out might not cause much trouble, shutter frames need to be square and properly fitted. Windows, meanwhile, are rarely as straight and square as they look. So, how do you measure for shutters properly? Here’s what you need to know before you reach for that tape measure!
Which measurements do you need for shutters?
The first thing to know is that you need more than one width and one height measurement. Sounds confusing doesn’t it but let us explain. For a standard window, a professional shutter survey will usually take three width measurements across the reveal: at the top, middle and bottom. Then you’ll take three height measurements: down the left, middle and right sides.
For larger openings, additional measurements may be taken along the run to make sure any variations are picked up. The reason for all this is because your window opening might not be perfectly square. Taking just one measurement at the top and bottom could easily miss that.
Why is the smallest shutter measurement the most important?
This is probably the part of shutter measuring that feels a little backwards. A shutter frame needs to be manufactured square. Your window opening doesn’t necessarily have to be. So rather than averaging your measurements, or simply using the largest measurement, the smallest measurement from each set is used. This makes sure the square shutter frame can fit into the entire opening. It also means you may end up with slightly different gaps around the frame. That’s completely normal.
If one side of the window is slightly wider than another, the frame can’t simply follow the shape of the opening. It needs to stay square, so the shutter doors hang correctly and open and close properly. This is also why a shutter installation can look a little odd halfway through. The gaps aren’t necessarily going to look even until the frame has been packed, trimmed and finished.
How far do shutters stick out from the window?
One of the most common questions we get is how much space shutters need in front of the glass. For a standard louvre size, you should allow roughly 10cm from the window to the front of the shutter frame. Larger louvres can project slightly further.
That space isn’t just taken up by the shutter itself. You also need room for things such as your window handles. Around 40mm of that allowance can be needed for a typical handle, with the rest allowing for the frame.
If you’re measuring your own window, check the depth of the reveal from the glass to the front face of the wall. If you’ve got less than around 10cm, don’t panic. It simply means the shutters may sit slightly proud of the recess. Windows without handles, such as fixed panes, can sometimes allow the shutter to sit further back.
Inside reveal fix or Z frame?
There are two common shutter frame options, and the one you choose affects how the shutters are measured and how they look when fitted. An inside reveal fix places the shutters as far back into the recess as possible. This leaves more of the windowsill visible in front of the shutters and gives a deeper, more recessed appearance. A Z frame sits towards the front of the recess. This allows the shutter doors to open back against the wall either side of the window, giving that classic continental shutter look.
It’s important to make sure the fixing is considered before measuring because the two options are fitted differently.
How do you measure shutters for a bay window?
Bay windows are typically much more complicated. You can’t simply measure each section and assume the angles will be standard. Even a five-sided bay can have different angles at each junction. For a professional survey, sections of shutter frame can be placed on the windowsill to establish the actual angle between each section. This is repeated around the bay so that each shutter can be made to fit its individual part of the window.
The finished result might be several individual shutters, but the frames are joined together during installation, so they look like one continuous run around the bay. The same projection needs to be maintained around the whole bay too, so the finished line looks consistent. In other words, measure bay window shutters as a complete system rather than treating each window as a separate rectangle. It’s one of those jobs where a professional survey is well worth having rather than attempting to DIY it.
What happens if your window isn’t square?
This shocks lots of people, but most windows aren’t perfectly square. Even brand-new windows can have small variations, so don’t assume a newer property will automatically be easier to measure. Once the square shutter frame is positioned in the opening, it can be levelled using small spacers or packers. If the opening is particularly far out, the packing required can be surprisingly substantial.
The remaining gap is then dealt with during finishing. Smaller gaps can be filled, while larger ones may need a trim that is cut to follow the opening. Everything is then sealed neatly to leave a clean edge around the shutter. So, if you notice that the gap between the shutter frame and wall isn’t identical all the way around, that doesn’t automatically mean something has gone wrong. It’s often the result of getting a perfectly square frame to sit correctly inside an imperfect opening.
The mistake people make when measuring their own shutters
Getting the measurements wrong isn’t the only potential problem. One of the biggest mistakes is failing to look at the window itself before deciding how many shutter doors you need. For example, if your window has three panes but you order four shutter doors, the vertical lines won’t line up with the window mullions. From inside, you might barely notice it. From outside, however, it can be surprisingly obvious.
There’s also a practical issue, as if the shutter door doesn’t line up with an opening window, you may need to open more than one door to get to the handle. And once you’ve noticed a misalignment like that, it’s very difficult to unsee it.
Measuring for shutters: what to check
Before you start measuring, keep these points in mind:
- Look at the window first. Count the panes and consider where the shutter doors need to sit.
- Take at least six measurements: three widths and three heights.
- Use the smallest measurement from each set rather than averaging them.
- Check the reveal depth and allow roughly 10cm for a standard louvre and frame.
- Choose your fixing style before measuring: inside reveal fix or Z frame.
- Don’t expect every gap to be identical, a square frame in an out-of-square opening will naturally leave some variation.
- Don’t judge the installation halfway through, as the packing, trims and finishing make a big difference.
- Get a professional survey for bays. The angles need to be established rather than guessed.
Ready to measure up? Let us do it for you!
Shutters are one of those things where getting the measurements right at the start is essential. From working out the correct door configuration to checking the recess depth and dealing with uneven or angled windows, there’s a lot more to it than measuring the widest and tallest points.
If you’re considering shutters for your home, contact Reynolds Blinds to arrange a professional measure and quote. Our friendly surveyors can check your windows properly, talk you through the different fitting options and make sure your shutters are made to suit the space.