Choosing blinds that survive daily use on bi-fold doors

Why not just fit a standard roller or Roman blind?

A fixed headrail blind hangs in one plane in front of the glass. When bi-fold doors are opened, the panels fold back on themselves and stack to one side, projecting forward off the frame line by the thickness of the folded stack, often 150 to 250mm depending on the number of panels. A standard blind mounted close to the glass will be struck by the folding panels before they are even half open.

Perfect fit: the usual first choice

Perfect fit blinds clip directly into the bead of the door frame itself and move with the door leaf when it is opened, because the blind is mounted to the frame rather than to the wall or ceiling above. This means there is no separate headrail to clear the folding stack, since each blind travels with its own panel.

• No drilling into the door frame, which matters on new aluminium bi-folds under warranty.
• Each door leaf carries its own blind, so opening the doors opens the blinds section by section.
• Works with pleated or Venetian style inserts depending on how much light control you want.

Slim profile verticals: the alternative for wide openings

On a very wide bi-fold run, a single slim-profile vertical blind track mounted above the whole opening can work, provided there is enough clearance in front of the frame for the folded louvres to sit clear of the door panels when they stack. This needs to be checked against the specific door manufacturer's stacking dimension, not guessed.

Clearance and stacking: the measurement that decides everything

Before choosing a product, find out how far the folded door panels project forward of the closed door line, and in which direction they stack (usually to one end, sometimes split to both). Any blind or track needs to clear that projection through the entire opening cycle, not just when the doors are shut.

Threshold and floor level issues

Bi-fold doors often sit on a low profile track at floor level, and a blind that drops all the way to the floor can interfere with the track or catch underfoot traffic. Perfect fit blinds solve this neatly because they are mounted to the moving frame and lift with it, but on a fixed track vertical, agree a finished drop that clears the threshold with a small margin rather than running fabric to the floor.

Light control and privacy on glazed doors

Because bi-fold doors are usually the largest glazed area in a room, light control matters more here than on a standard window. Pleated perfect fit inserts give a soft, even light when closed, while Venetian style inserts let you angle the slats for privacy without losing daylight entirely.

Where a bi-fold faces a garden used after dark, consider specifying the same blind on every leaf even if you only intend to close a couple of them regularly, since a mix of dressed and undressed panels looks unfinished once the doors are folded back and stacked to one side.

Getting the survey right the first time

Because bi-fold clearance depends on door manufacturer specifications as much as the window opening itself, this is one job we would always recommend measuring at a home visit rather than from door brochure dimensions alone, since real world installation tolerances vary from the factory spec.

Handle clearance and door furniture

Bi-fold doors usually carry a handle on the active leaf and sometimes a espagnolette bolt or flush pull on the others, and any of these can protrude further into the frame than a standard window handle. A perfect fit blind clipped to that leaf needs its side channel positioned so the handle still has room to turn without catching fabric or slats.

Where a handle sits close to the top or bottom of the leaf, ask for the blind to be specified with a cut-out or offset bracket at that point rather than assuming a standard fitting will clear it. This is exactly the sort of detail that gets missed when a blind is ordered from door measurements alone rather than checked leaf by leaf on site.