The combination of a multi-point locking system, locking shoot-bolts, high security hinges and thermally toughened glass make our Bi-Fold Doors so secure, even a 200lb punch bag couldn’t break them in our strength test. The lock cylinder is tested to BS EN 1303 and internal glazing beads are also fitted to prevent glass being removed from outside, keeping you even safer. Extremely safe Bi-folding doors.

How to Measure

If you don’t have an existing door or frame in place, things are a little bit more complicated. Start by measuring the height of the brickwork opening in 3 places, on the left-hand side, in the centre and the right-hand side. Do the same for the width, measuring at the top, middle and bottom. Note down each set of measurements and take the average of each set to determine the size of the door opening.

If you’re ordering a door frame, you’ll need to allow a fitting clearance to make sure the frame fits into the door opening without forcing. If the frame gets forced at any point during the fitting process it can be knocked out of alignment which makes door fitting and operation difficult. The usual clearance to allow is 10mm. Deduct this from your previous calculations to find out what size you should opt for when ordering a door complete with a frame.