Measuring your Bifold Door Aperture

If you are intending to choose our supply and fit service our installer will carry out a survey to determine manufacturing sizes and installation requirements.

The following is intended as a brief guide for supply only customers to determining the width and height of your bifold door. Note that it is good practice to view and sketch the door “as viewed from the outside”.

STEP 1

Check that your aperture is square by comparing the cross-corner dimensions.

STEP 2

Measure the width of your aperture in three different places. Take the smallest size and deduct 10mm to provide your width dimension.

STEP 3

To determine the height of your door you should first decide where your finished floor level will be, including any floor covering. Download the Threshold and cill drawings and decide on the type of threshold you require and if the door is to sit on a projecting cill or direct onto the brickwork. 

Now that you have determined where the cill (or threshold) will sit you can measure the height of the door from underside of lintel to underside of the threshold or cill. Take three measurements in different places and use the smallest dimension from which you should deduct 10mm.

STEP 4

Decide on the style (view styles) of your door and the position of any traffic door. On styles that provide a double traffic door you can specify which door leaf is to act as the master door. All our folding doors can be supplied to open in or out. The most popular option is opening outwards which maximises space inside the room.

STEP 5

Decide if your door requires trickle vents fitted. If the door is being installed into a new aperture it will usually require trickle vents to conform with current building regulations. If the door is being installed into an existing aperture trickle vents are not mandatory but recommended, especially if the door is being installed into a kitchen area.

Trickle vents are normally supplied fitted to a 42mm frame extender that is fitted to the top of the frame.  Please note that standard trickle vents are only available in white, brown or black.  Metal trickle vents can be provided at extra cost powder painted to match the colour of your door.