The threshold is the first place to look
Every UK home-lift door — whether swing, bi-parting or single-slide — closes against a threshold strip on the car sill and, on landing doors, on the shaft sill. Any debris in that strip will either physically stop the door or defeat the sensor that confirms it is fully home:
- Post, mail, a receipt or a leaflet.
- A phone charger cable, hearing-aid battery or coin.
- Grit and small stones tracked in from the garden.
- Pet hair compacted into the sensor recess (especially where the light curtain lives).
Sweep the threshold with a soft brush — never poke a screwdriver or metal object into the recess, which can damage the reed switch or light-curtain lens.
Check the door-hold-open button hasn't been pressed
Most UK home lifts have a labelled door-hold-open button inside the car — often marked with an open-door icon. Once pressed, the door stays open until the button is pressed again or the button times out (usually 60–120 seconds). If a child, cleaner or delivery driver has held the button, the door will refuse the close command.
Swollen doors in winter and after leaks
Timber-framed landing doors — common on early Stannah and Terry Lifts installations in UK period properties — swell in cold, damp weather and after any water event. A door that has been closing fine all summer and suddenly won't latch in November is almost always a swelling problem. Do not plane the door yourself; contact your service provider, who will refit and re-align the door on a service visit.
In the meantime, avoid slamming the door — that stresses the interlock latch and can bend it out of tolerance.
Not sure which brand or model you have? Send us the symptom in plain English and we’ll point you at the right diagnostic page for free.
Describe your symptom →Light-curtain and safety-edge blockages
Modern home lifts (Cibes, Aritco, later Stannah models) use an infrared light curtain across the door opening. If any element of that beam is blocked, the door will start to close, then reverse:
- A finger or bag strap trailing through the opening.
- Sunlight through a shaft window hitting the receiver lens (rare but real in south-facing installs).
- A hanging plant or drying laundry moving in a draught.
- A greasy or dusty lens film — wipe both sides of the doorway with a dry microfibre cloth, never solvent.
The interlock catch itself
Every landing door has a mechanical catch — a hooked bolt that drops into a slot in the frame when the door reaches the fully-closed position. This is what physically prevents anyone opening the door when the car isn't present. If the catch bracket has been knocked out of alignment (a pushed pushchair, a chest of drawers scraped past, a cleaner leaning on the door with a mop), the door will close visually but the catch won't drop the last millimetre.
You can see this: with the door closed, look at the edge where door meets frame. A gap of more than 3 mm — or an audible failure of the ‘clunk’ when the door reaches home — indicates a misaligned catch. This is engineer work.
When to stop and call
Stop — call an engineer
Stop attempting to close the door and phone your service provider if:
- The door closes but the lift then shows a warning light and refuses the call.
- You can see a broken glass panel, damaged hinge or bent frame.
- The door slams shut on its own — the door closer has failed and can trap fingers.
- Water is running down the shaft wall (a sealed shaft that has taken a leak needs urgent electrical isolation).
Frequently asked questions
- Is it OK to hold the door closed manually while someone presses call?
- No. The interlock has to prove the door is closed by its own catch, without human help. Holding the door will not fool the safety chain and can strain the latch mechanism. Fix the cause of the failed close instead.
- My car door closes but the landing door doesn't — what's the priority?
- The landing door. UK lift safety design requires the landing door to be fully closed before the car door will close in most brands. Diagnose the landing door first; the car door problem usually disappears with it.
- Can I lubricate the door tracks myself?
- A light spray of PTFE dry lubricant along the top track once a year is fine on most brands. Never use WD-40, oil or grease — they attract dust, gum up the tracks and void some warranties. When in doubt, leave lubrication to the annual service.
- The door beeps when it tries to close but doesn't. What's happening?
- The controller has sent the close command, the motor has started, and something has interrupted the movement — usually the light curtain or safety edge. Check the sensors are clean and unobstructed; if the beep persists with a clean sensor, that sensor has failed and needs replacement.
- Do UK regulations require the lift to have automatic doors?
- Machinery-Directive home lifts must have interlocked doors that prevent car movement when open, but they don't have to be power-operated. Many UK cabin lifts and most through-floor lifts still use manual doors, which are simpler and cheaper to maintain.