Measuring windows for blinds

Custom window coverings are made to the sizes you give, so accurate measuring is the most important step in buying them. Mistakes can be expensive, because made-to-measure products often can't simply be returned. Take your time, measure carefully and, if in doubt, ask the supplier to check-measure.

This is general information. We don't publish prices or recommend particular brands or businesses.

Tools you need

• A steel tape measure (fabric tapes stretch);
• a pencil and paper, or our measuring planner;
• a step ladder for tall windows, used safely;
• a helper for wide windows.

Step 1: Decide inside or outside mount

An inside mount sits within the window recess. An outside mount is fixed to the wall or frame and overlaps the opening. The choice changes what you measure. See inside or outside mount.

Step 2: Measure the width

For an inside mount, measure the width of the recess at the top, middle and bottom. Record the smallest figure. Don't make your own deductions unless the supplier asks you to.

For an outside mount, measure the opening, then decide how far you want the covering to extend beyond it on each side.

Step 3: Measure the height (drop)

For an inside mount, measure from the top of the recess to the sill at the left, middle and right. Record the smallest figure.

For an outside mount, measure from where the brackets will sit to where you want the covering to finish.

Step 4: Check obstructions

Note handles, winders, locks, alarm sensors, architraves and anything else that might stop a covering sitting flat or operating properly. Check the recess depth for inside mounts, because some systems need a minimum depth.

Step 5: Label everything

Give each window a name and record width first, then height. Note the mount type and any obstructions. Photograph each window.

Common mistakes

• Swapping width and height;
• measuring with a fabric tape;
• forgetting handles or winders;
• rounding measurements;
• measuring only once.

Unusual windows

Arched, angled, corner, skylight and very tall windows can be harder to cover. Some products suit them better than others, and some suppliers specialise in them. Measure carefully, take photos, and ask suppliers what's possible and how they would approach each window. For skylights and high windows, think about how the covering will be operated, as motorised or pole-operated options may be easier.

Use the measuring planner

Our free measuring planner helps you list each window, record inside or outside mount sizes, and print a tidy sheet to take to suppliers. It reminds you about cord safety, and nothing you enter leaves your browser. It doesn't apply manufacturing deductions; suppliers do that based on their products.

Measure-and-install yourself?

Some retailers sell made-to-measure coverings that you measure and install yourself. This can suit confident DIYers, but you take responsibility for measuring accurately and installing safely. Read the instructions before you order, check you have the right fixings for your walls, and use a ladder safely. If the coverings have cords, install the supplied cord safety devices exactly as instructed so the installation meets the national standard.

A quick checklist

Before you order:

• decide what each covering needs to do;
• choose the mount type;
• measure carefully, in millimetres;
• see samples at home;
• get like-for-like written quotes;
• check the business and its ABN;
• confirm lead times, warranty and terms;
• plan for cord safety.

Keep good records

Keep a simple record for each room: product, fabric or material and colour, supplier, date installed, care instructions and warranty. Photograph the labels or swing tags before you remove them, and keep the cord safety warning labels and instructions. These records help if you need a repair, a matching replacement, or to make a warranty claim, and they're useful if you sell the home.

Questions to ask yourself first

Before you start, think about what you want your window coverings to do. Is the priority privacy, darkness, glare control, warmth, looks or easy cleaning? How often will each covering be opened and closed, and by whom? Are there young children in the home? Do any windows have handles, winders or unusual shapes? Do you rent or own? What's your timeframe? Short answers to these questions make it much easier to compare products and quotes, and to explain what you need to suppliers.

If you rent

If you rent, check your rental agreement and talk to your rental provider or agent before drilling holes or replacing window coverings. Consumer Affairs Victoria has information about the changes renters can and can't make. Removable options, such as tension rods or freestanding screens, may suit some situations. Keep any original coverings you remove, and take photos so you can restore the property at the end of the tenancy.

Where our information comes from

We base the safety and energy information in this guide on official sources, including ACCC Product Safety Australia, the Federal Register of Legislation, YourHome, Sustainability Victoria, energy.gov.au and Consumer Affairs Victoria, listed at the end of the page. Practical tips about products are general guidance only. Requirements and guidance change, so we show the date we last checked the page. Before relying on any detail, follow the source links.

Getting help from suppliers

Good suppliers will explain options clearly, bring samples, measure carefully and put everything in writing. Don't be afraid to ask questions, including why they recommend a particular product, what alternatives exist, and how the covering will be fixed and operated. Ask to see examples of similar installations. If a supplier can't answer clearly, or pressures you to sign on the spot, take your time and get another quote. A clear, unhurried conversation is usually a good sign that the rest of the process will go smoothly too.

Living with your choice

Once coverings are installed, give yourself a few weeks to see how they work through different weather and light. Notice whether rooms feel warmer, darker or more private, and whether coverings are easy to use. If something isn't operating properly, contact the supplier early rather than waiting. Small adjustments, such as tension on a chain or alignment of a shutter panel, are often simple to fix soon after installation. Make a note of anything you'd do differently for the next room.

Accessibility and ease of use

Think about who will be operating each covering. Heavy blinds, high windows and stiff controls can be hard for some people to use, including older people and people with limited reach or grip. Motorised controls, wands, lighter fabrics and splitting wide windows into smaller coverings can make daily use easier. Ask suppliers to demonstrate controls before you order, and consider where switches or remotes will be kept.

Sustainability

Choosing durable coverings, caring for them well and repairing rather than replacing can reduce waste. Ask suppliers whether replacement parts are available, whether fabrics can be cleaned, and what happens to old coverings when they are removed. Coverings that help reduce heating and cooling needs can also help lower energy use, as YourHome and Sustainability Victoria explain. Avoid vague environmental claims and ask suppliers to explain any they make.

Measuring for curtains

Curtains are measured differently from blinds. Decide where the track or rod will go and how far it will extend past the window on each side, which affects how much glass is covered when the curtains are open. Measure the drop from the track to where you want the curtain to finish, whether at the sill, below the sill or at the floor. energy.gov.au suggests curtains that reach the floor and wrap to the wall for better temperature control. Ask the supplier how much fullness (extra fabric width) they allow, and record whether you want a pelmet.

Double-check before you order

Before you send measurements, measure every window a second time, ideally on a different day or with a different person. Compare the two sets. If anything differs by more than a few millimetres, measure again. Check that each figure is labelled width or height and that the mount type is noted. This small step catches most errors before they become expensive.

Key points

• Use a steel tape and record in millimetres.
• Measure width and height in three places; use the smallest.
• Note obstructions and recess depth.
• Label each window clearly.
• Ask whether a check-measure is included.