How to measure for a Door - Bi-Fold Door
The first thing to check is if the opening for the door is of a sound structure - to allow the bi-fold door to be installed correctly and safely.
The opening walls and floor must be constructed from structural timber, steel, brick, concrete or concrete block. Thermalite (or similar), cinder blocks or breeze blocks are not suitable to obtain a firm structural fixing.
The head of the opening must also be constructed from steel, structural timber or concrete.
Light metal lintels and timber sub-frames are not suitable to obtain a firm structural fixing.
The next step is to measure your opening
We recommend that you allow between 10mm (25/64 inch) to 20mm (25/32 inch) of tolerance between the opening structure and the door frame to allow ease of installation.
It is also advisable to use a large spirit level to check the opening, as an opening that is not level can effect your measurement. Note: Always use the smallest measurement.
Always include your chosen bottom track option in your measurements and remember to allow for floor finishes, tiles, carpet etc. Note: the frame height includes the bottom track.
Measure from wall to wall (side to side) of the prepared opening, then minus a tolerance of between 10-20mm or 25/64-25/32 inch in your measurement to allow for fitting tolerance.
Measured from the underside of the top support to the underside of the bottom track (top to bottom), then minus a tolerance of between 10-20mm or 25/64-25/32 inch in your measurement to allow for fitting tolerance.
Square Metre / Feet
Area of the door; width X height equals the Sq/Mt (Sq/Ft) of the door, weight is approximately 30kgs per Sq/Mt (6 psf) based on a double glazed standard unit.
When deciding the way that you would like your threshold to be situated, always make allowances in your measurement to accommodate the bottom track.
Note: the frame height includes the bottom track. We fit the flush track as standard, please allow for the 43mm (1 11/16inch) profile depth if choosing this option
Inward or outward opening doors
Once you have your opening size you need to decide which direction you would like you door to fold and if you would like it to fold to the left or to the right or both.
Folding sliding doors are custom made to your measurements and can be up to 4000mm (4m / 13ft) high and 15000mm (15m / 30ft) wide (depending on which material you choose, please see system specification on the corresponding product page). The maximum panel width being 1000mm (39⅜”). Depending on the system you require.
Folding sliding doors are always viewed from the inside, so when ordering always give the opening direction of your door as you look at it from the inside.
To help assist in the measuring process we have a cheat sheet for each threashold type, simply print and complete.
IF UNSURE ON MEASURING why not book a ‘Site Survey’ on 0345 64 64 646