Bi-fold doors
Bi-fold doors fold back on themselves and stack at the side, opening nearly the whole wall. On mid-size openings they give the widest clear opening for the money.
How it works
Panels are hinged to each other and hang from, or roll along, a track. Pull the lead panel and the rest follow, folding into a stack at one or both jambs.
Top-hung systems carry the weight in the head track, so the header must be stiff. Bottom-rolling systems carry the weight on the sill, so the floor must be level and solid.
Many bi-folds include a traffic door, a single panel that opens like a normal door for daily use without folding the whole system.
What we check on every install
- Header stiffnessOn top-hung systems a sagging header makes panels drag and bind.
- Level floorOn bottom-rolling systems the sill track must be level along its full length.
- Stack spaceRoom for the folded panels inside or outside, clear of furniture, rails and lights.
- Hinge and carrier set-upPanels adjusted so they fold and close in line, with even gaps.
- Sill drainageOut-folding doors especially need a drained sill and pan.
Questions we hear
Bi-fold or multi-slide?
Bi-folds open more of the wall and handle mid-size openings well. Multi-slides have slimmer views when closed and suit very long openings or pockets.
Do bi-folds leak?
A well-installed system with a drained sill and adjusted seals performs well. Leaks usually come from a missing pan or panels out of adjustment.
Should the panels fold in or out?
Out-folding keeps the room clear and sheds water better; in-folding keeps the stack out of the weather.
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