How to measure for shutters

Inside mount

The frame sits inside the window opening. It looks built in, and it’s what most people choose.

1. Check the depth. Measure from the front edge of the opening back to the glass, or to the first thing that sticks out: a handle, crank, lock or alarm sensor. Louvers need room to tilt, so we check this against the louver size you pick.
2. Measure the width three times. Measure inside the opening at the top, the middle and the bottom, to the nearest 1/8 inch or millimetre. Write down the smallest.
3. Measure the height three times. Measure at the left, the centre and the right. Write down the smallest.
4. Check it is square. Measure both diagonals, corner to corner. If they differ by more than about 1/4 inch (6 mm), say so in the notes; an out-of-square opening may suit an outside mount better.
5. Note what is in the way. Handles, window cranks, alarm sensors and deep sills all affect how the frame sits. List them in the notes for that window.

Enter the exact opening sizes. Don’t subtract anything for clearance; we make the fitting allowances.

Outside mount

The frame sits on the wall or trim around the window. Choose it when the opening is shallow, out of square, or has something in the way that an inside mount can’t clear.

1. Decide how far past the opening you want the frame on each side. Most people cover the trim.
2. Measure the total width and height you want covered, at the widest and tallest points.
3. Check the surface all the way around is flat enough for the frame to sit against.

Before you send it

• Name each window in a way you’ll recognize on delivery day, such as “Kitchen sink” or “Bedroom 2 left”.
• Take a photo of each window from straight on. We may ask for it if a size looks unusual.
• Measure anything that looks borderline a second time.