How to Measure for Bifold Doors

Why Accurate Measurements Matter

Getting your bifold door measurements right first time saves money, avoids delays, and ensures a draught-free, secure fit. All of our bifold doors are made to measure, so the dimensions you provide go straight to the factory floor.

Tools You’ll Need

• A steel tape measure (at least 5 m)
• A spirit level (1 m minimum)
• A pen and paper — or use our printable measurement sheet

Step 1 — Measure the Width

Measure the structural opening (brick to brick) at three points: top, middle, and bottom. Record the smallest of the three figures — this is your ordering width. Our factory will make micro-adjustments for a precision fit.

Step 2 — Measure the Height

Measure from the top of the opening to the finished floor level (or top of threshold if one is fitted) at three points: left, centre, and right. Again, take the smallest reading as your ordering height.

Step 3 — Check the Opening Is Square

Measure both diagonals. If they differ by more than 10 mm the opening may need building work before the doors are fitted. Our technical team can advise if you’re unsure — just send us your measurements.

Step 4 — Note the Threshold Type

Decide whether you need a low aluminium threshold (ideal for wheelchair access and flush floor transitions) or a standard UPVC threshold. This can be selected during the order process.

Step 5 — Choose Your Configuration

Bifold doors come in 2 to 7 panel configurations that fold left or right. Think about which way you’d like the panels to stack and where you want the traffic door. Our configurator lets you preview every option.

Common Mistakes to Avoid

• Measuring the old frame instead of the structural opening
• Forgetting to account for floor build-up (tiles, underfloor heating, etc.)
• Not checking the opening is plumb and level

If in doubt, drop us a message with photos and your rough measurements. Our team will double-check everything before production begins — it’s all part of the service.