Small bifold doors

Bifold door sizes: think in leaves

On both our profiles a leaf goes up to 1,200 mm wide, 3,000 mm high and 120 kg; Aluprof gives 700 mm as the narrowest leaf of the Fold Line HD. The width of your door follows from how many leaves you want and how wide they are, not from one fixed size.

2m bifold doors

The 2-panel bifold door: standard 1,900 × 2,300 mm, up to 2.05 m wide. It has no separate traffic door, so you fold the whole door open to walk through. It suits a small patio or a balcony.

3m bifold doors

The 3-panel bifold door: standard 2,800 × 2,300 mm, up to 3.00 m wide, with a traffic door that opens like an ordinary door and two leaves that fold away. For an opening of 3.2 m you move up to the 4-panel layout.

4m bifold doors

The 4-panel bifold door: standard 3,600 × 2,300 mm, up to 4.00 m wide, with a pair of traffic doors and two folding leaves. Reynaers gives the ConceptFolding 77 with four panels up to 4,000 × 2,700 mm overall.

5m and 6m bifold doors

The 5-panel bifold door is standard 4,500 × 2,300 mm, up to 5.00 m wide, with one traffic door. The 6-panel is standard 5,400 × 2,300 mm, up to 6.00 m wide, with a pair of doors. At that width, have a builder check the lintel first.

The folded stack

When the door is open, the leaves stand folded against the reveal on one side. The more leaves, the bigger that stack. Measure the space beside the opening, inside or outside depending on which way the door folds.

Working out the leaf width

Before you open the configurator, divide the width of your opening by the number of leaves you have in mind. The result is roughly the width of each leaf, a little less in practice because the outer frame takes its share. It has to stay under 1,200 mm on both profiles, and on the Fold Line HD it cannot drop below 700 mm.

Two examples. An opening of 3,000 mm over three leaves gives about 1,000 mm per leaf; over four leaves, about 750 mm, which is still above the Fold Line HD minimum but means more joints and less glass. At 6,000 mm, six leaves come to about 1,000 mm each. Six leaves at the full 1,200 mm would reach 7,200 mm, but our widest layout stops at 6.00 m, so at the top of our range the layout sets the limit, not the leaf.

2-panel bifold doors: which profile

Aluprof describes the MB-86 Fold Line HD as a door set of three to eight leaves. Reynaers gives two to eight panels for the ConceptFolding 77, so for a 2-panel bifold door that is the profile whose manufacturer starts at two. The configurator shows which profiles it offers once you have picked the layout.

Height: 2,300 mm and taller

All five standard sizes are 2,300 mm high. You can go taller, as both manufacturers allow leaves up to 3,000 mm. A taller leaf carries more glass, though, and the limit of 120 kg per leaf doesn't move, so height and width draw on the same weight budget. Reynaers states its four-panel set at up to 4,000 × 2,700 mm overall: a reminder that the size of the whole door and the size of one leaf are separate limits.

What the threshold and head track take from the height

The overall height you enter includes the frame at the top and the threshold at the bottom. On the ConceptFolding 77 the head track the panels hang from is 42 mm and the low threshold 25 mm. On the Fold Line HD the low threshold stands 3.5 mm above the floor; the surface-mounted version with a rebate seal is higher and leaves a step of a few centimetres. Settle the threshold before you measure the height, because it decides where the frame starts.

Measuring the opening for a bifold door

Take the width at the top, in the middle and at the bottom, and the height on the left and on the right. Use the smallest reading each time and subtract the fitting gap your installer asks for. The wider the opening, the more one reading can mislead you.

Look at the floor as well: the level inside and outside, and what is underneath where the bottom track will run. Then check the wall beside the opening on the side where the leaves will gather, for radiators, downpipes or window frames that would stop the stack from folding right back.

How close we make it to your size

We make the door to the overall size you enter. Above one metre, which every bifold door is, the tolerance is ±3 mm on width and height, with no more than 2 mm between the diagonals. If a door we deliver is outside that, we make it again free of charge. A size that was measured wrong is not covered, so if you are unsure, have your installer take the measurements or check yours.

Further reading

• Bifold doors
• Bifold doors cost
• Black bifold doors
• Slimline bifold doors
• Narrow French doors
• Doors