Slimline bifold doors
Slimline bifold doors with us are aluminium: 108 to 119 mm in view at the side of the door, and a joint between two panels down to 122 mm in the Reynaers SL version. A bifold always shows two profiles per leaf, so it never gets as slim as a lift-and-slide door.
Slim aluminium bifold doors: the sightlines
On the Aluprof MB-86 Fold Line HD, frame and leaf together are 108 mm in view at the side, with a 12 mm gap where two leaves meet at the hinge. On the Reynaers ConceptFolding 77, frame and panel are 119 mm at the side and the hinge joint between two panels is 144 mm.
Slim frame bifold doors: the SL version
Reynaers makes the ConceptFolding 77 in an SL version with a narrower joint between the panels: 122 mm instead of 144 mm. If you want it and the configurator doesn't list it for your size, ask for it in the comments of your request.
Fewer, wider leaves
Every leaf brings two profiles, so fewer leaves means more glass and fewer joints in view. With leaves up to 1,200 mm wide, choose the widest leaves your opening and the weight limit of 120 kg per leaf allow.
Modern bifold doors: threshold and corners
A low threshold keeps the floor running from inside to outside: 3.5 mm above the floor on the Fold Line HD, with drainage on both sides. The Fold Line HD also comes in corner and panoramic configurations, so two walls meeting at a corner can both open.
Bifold doors for contemporary homes: colour
A slim aluminium profile in anthracite RAL 7016 or black RAL 9005 suits a modern house. The aluminium is powder coated, so any RAL colour the configurator shows is possible.
How much glass you actually see
Each leaf is one pane held between two profiles, so the glass is always narrower than the leaf. In the Reynaers drawing of a three-panel ConceptFolding 77, the panes measure 994, 1,006 and 999 mm across. Those are the widths of that one door, not a standard: your own panes follow from your overall size and the number of leaves.
The traffic door joint
From three leaves up, one leaf works as an ordinary door, and where it closes against its neighbour the joint is a little wider than at a hinge because the lock sits there. On the ConceptFolding 77 that joint measures 154 mm, against 144 mm between two folding panels. The 2-panel layout has no traffic door and so no lock joint either; you fold the whole door open to walk out.
Top and bottom of the door
A bifold hangs from a track at the head. On the ConceptFolding 77 that head track is 42 mm and the low threshold at the foot is 25 mm; at top and bottom you see 127 mm of frame and panel together. Reynaers offers four threshold options, from fully level to a high-performance version that resists driving rain up to class 9A. The level one looks cleanest from inside; the high-performance one is worth weighing up on an elevation that takes the weather head-on.
Handles that fold flat
Only the leaf that opens first has a handle. The others have a recessed flush pull, because anything standing proud would get caught when two leaves fold together. That keeps the outside face of the door almost flat. The handle colour is a choice of its own, and handle, backplate and flush pulls then all come in that colour; black and anthracite are among the options. Lockable handles carry SKG 2 stars, a Dutch hardware rating tested to NEN 5089, which is not a UK certification for the door as a whole.
A different colour inside
The inside and outside of the frame can have different colours. Black or anthracite outside with white inside, for example, gives a dark line on the elevation and a light frame in the room. Powder coating comes smooth or textured; the configurator shows which finish each colour has.
Large panes down to the floor
On a bifold door the glass starts close to the floor, and glass in that position may have to be safety glass. Your installer or building control can tell you which panes that applies to. We supply laminated P4A safety glass in double and in triple glazing; if such a pane breaks, the fragments stay on the interlayer.
Frequently asked questions
What are the slimmest bifold doors you supply?
At the side of the door, the Aluprof Fold Line HD, with 108 mm in view. Between two panels, the Reynaers ConceptFolding 77 SL, with a 122 mm joint.
Are slimline bifold doors as slim as sliding patio doors?
No. A lift-and-slide door has less profile in view and larger panes. Choose sliding for the view and bifold for an opening that has to be completely clear.
Do slim bifold doors insulate less well?
That depends on the profile, the glass and the number of leaves. For the ConceptFolding 77 Reynaers gives a frame Uf of 1.66 W/m²K; the U-value of your whole door is in your quote.
Can a bifold door have a level threshold?
Yes, on both profiles. The Fold Line HD has a low threshold 3.5 mm above the floor, and the ConceptFolding 77 has a fully level option among its four thresholds. On the Fold Line HD that low threshold needs drainage inside and outside, so settle it before the floor is laid.
Can I have black handles on anthracite doors?
Yes. The handle colour is chosen separately from the frame colour, and black is one of the options. The flush pulls on the other leaves follow the handle colour.
Do slimline bifold doors suit an older house?
On the back of an ordinary house, often yes. On a listed building or in a conservation area a wall that folds open is a modern change, so ask your local planning authority before you order, and mention it in the notes of your request.
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