Most bifold door problems come down to three things: dirt in the track, panels that have dropped out of adjustment, or a frame that was not fitted level and square. Cleaning the track and running gear fixes a surprising number of sticking doors; dropped panels need the rollers or hinges adjusting; leaks and doors that won't lock usually point to alignment or worn seals.
Here are the common symptoms, what causes each one, and what you can safely check before calling someone.
Doors that stick or are hard to slide
Grit, leaves and pet hair build up in the bottom track and rollers. Vacuum the track, wipe it with a damp cloth and check the rollers turn freely. Avoid heavy grease, which collects dirt; follow the manufacturer's advice on lubricant. If the doors still drag, a roller may be worn or broken.
Panels that have dropped or catch
Bifold panels are heavy, and over time hinges and carriers settle so the leading edge rubs the frame or the panels don't meet evenly. Most systems have adjusters on the top or bottom running gear. Adjustment is fiddly and panels are heavy, so this is often best left to a fitter.
Draughts and water getting in
- Worn or displaced brush and gasket seals
- Panels out of alignment so seals don't compress
- Blocked drainage in the bottom track
- Poorly detailed threshold on an exposed elevation
Doors that won't lock
If the handle won't turn fully or the key is stiff, the locking points aren't meeting their keeps — usually because a panel has dropped. Don't force the handle, as that damages the gearbox. Realigning the panel often cures it; a broken gearbox needs replacing.
When to call a fitter
Call for help if a panel has dropped noticeably, a roller or hinge is broken, the glass is cracked or misted, the doors won't lock, or water is coming in. Bifold problems that appear soon after fitting often trace back to the frame not being level; correct fitting matters more on bifolds than on almost any other door.
Common questions
Usually dirt in the track or a worn roller. Clean the track first; if it still drags, the running gear may need attention.
Most systems have adjusters, but panels are heavy and adjustment is fiddly, so a fitter is often the safer option.
Yes. The sealed unit can be replaced in the existing panel.
Yes. Call 07538 882579 or use the contact form to arrange a visit.
Want a straight answer on your own windows or doors?
DM Installations fits and repairs windows and doors across Central Scotland — Cumbernauld, Glasgow, Falkirk, Stirling and the surrounding towns. Free survey, written quote, and an honest answer on whether you need a repair or a replacement.
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