Modern UPVC doors and windows are in most of Bristol’s homes, but they are not completely maintenance free. UPVC lock and hinges really benefit from a little TLC which can help their long term condition. Follow the tips below and you will be able to minimise the wear on your UPVC fittings for a longer product life.
1. Oil the working parts
Oil the locking strip on the edge of the door or window at the very least annually (it’s best every 6 months). Here’s where all the bolts and other locking parts operate. Open the door or window and use the handle through full normal rotation up and down to work the oil into all the moving parts. If any of these parts have failed its likely best to call out your local locksmith for UPVC lock repairs.
Important note about oils (updated for 2026)
Don’t reach for standard WD-40 as your go-to lock lubricant. The original blue-and-yellow WD-40 Multi-Use is brilliant at displacing water and freeing seized parts, but it’s a light oil — left inside a lock cylinder or multipoint mechanism it eventually goes tacky, attracts dust, and gums up the very moving parts you wanted to free. We see the results of this on call-outs every week across Bristol.
What you want is a dry lubricant — one that goes on wet to flush the mechanism, then dries to a non-sticky film that won’t collect grime. The current options we’d recommend in 2026:
- APECS Dry Lube — still our preferred professional choice. It’s a polarised dry lubricant designed specifically for locks and cylinders. Goes on wet, displaces moisture, dries to a clean film, and works from -47°C to +170°C. Sold in a small 50ml bottle (no aerosol, no propellant), available from APECS direct, Amazon UK, and most locksmith suppliers.
- WD-40 Specialist Anti-Friction Dry PTFE Lubricant — the dry PTFE spray from WD-40’s Specialist range (not the standard blue-and-yellow can). Widely available at Toolstation, Screwfix, Amazon, and most DIY shops. The Smart Straw applicator makes it easy to get inside lock cylinders and along the locking strip.
- WD-40 Specialist Dry Lubricant (PTFE-free) — the newer PTFE-free version in the same Specialist range, if you’d rather avoid PTFE. Performs the same job in lock applications.
- GT-85 — was a long-standing favourite of the trade, but worth a word of caution: GT-85 reformulated their main spray and the everyday “Multi-Purpose” can no longer contains PTFE. The PTFE version is still sold by some retailers but check the can carefully before buying. If in doubt, the WD-40 Specialist Dry PTFE is a more reliable shelf-find now.
A word on cylinder-specific lubricants. Some high-security lock manufacturers (Ultion, Yale Platinum 3*, Mul-T-Lock and others) specify their own lubricant to keep the warranty valid. If you’ve got a 3-star cylinder still under warranty, check the manufacturer’s instructions before applying anything else — using the wrong lubricant can void the cover.
How to apply. Open the door or window, spray a short burst onto the locking strip on the edge of the door (where the bolts, hooks and rollers operate), then work the handle through its full up-and-down rotation several times to draw the lubricant into the moving parts. Wipe any excess away with a soft cloth. For the cylinder itself, a small amount sprayed into the keyway then the key worked in and out a few times is plenty — more is not better.
When to call a locksmith
These tips will keep most UPVC locks running smoothly for years. Lubrication and a regular wipe-down genuinely do prevent the majority of the lock failures we get called out to.
That said, if your lock has already failed, snapped, started turning without engaging, or feels misaligned — no amount of lubricant will fix it. The mechanism is mechanical: once a gearbox has stripped, a cylinder has snapped, or the multipoint hooks have come out of true with the keeps, it needs a repair or a replacement.
If you’re in Bristol or the surrounding area and any of the following sound familiar, that’s when we get the call:
- Handle lifts but the key won’t turn (or turns without engaging the bolts)
- Door has dropped on its hinges and won’t pull up to lock cleanly
- Key snapped off in the cylinder
- Cylinder feels loose, wobbly, or has been attempted on (snapped, drilled or bumped)
- Lock is stiff even after a proper lubrication
We cover Bristol and the surrounding area 24 hours a day. See our UPVC lock repair page for what’s involved, or call us on 0784 666 2889 if it’s urgent.
2. A quick clean
Thankfully, UPVC doors and windows are much lower maintenance than traditional wood products. However, a regular once over of your door, windows and frame with some soap and water makes a long term difference in preventing the build up of any dirt or grime. It’s possible for muck to build up over time and cause problems for door or window mechanisms.
To clean the frames and panels of your UPVC doors and windows, you only need a soft sponge and warm soapy water. Don’t use anything abrasive as micro-scratches will only encourage grime to take hold. The soap doesn’t need to be fancy it can be normal hand soap or washing up liquid. Just be thorough and clean all around all the surfaces. Remember to start from the top and work your way down. Finally, dry the surface with a soft cloth.
We really recommend avoiding harsher chemicals (certainly anything with ammonia in it) or any kind of solvent as they might damage UPVC or other fittings, and you shouldn’t need them to shift the dirt. Same goes for any door furniture hardware attached like handles, knockers, hinges, letterbox, etc. Here you can buff to a shine once clean and dry.
3. Other bits
Inspect the seals when you clean. The rubber seals can be a little trickier than the UPVC itself. Here it’s best to be really careful with chemicals, as even some non-abrasive ones may cause the seals to peel. So again, soapy water works great. Grime can build up in the corners, especially on the external side, but be careful not to poke too hard at them.
Ventilation control should be maintenance free! Some UPVC windows are fitted with a simple trickle ventilation unit, found along the top of the frame. This is built so that you can control ventilation and minimise any build up of condensation. You can open or close most ventilators by moving a control to the left or right. No maintenance is required.
Frequently asked questions
How often should I lubricate UPVC door and window locks?
Once every six to twelve months is the sweet spot for most UK homes. Annually is the bare minimum — every six months is what we’d recommend, especially for exposed front doors, coastal properties, or doors that get heavy daily use. Many multipoint mechanisms have small oil-can icons stamped on the locking strip showing the manufacturer’s recommended lubrication points; these are worth following.
Can I use WD-40 on UPVC door locks?
The standard blue-and-yellow WD-40 Multi-Use is fine in an emergency to free a seized lock, but it’s not a long-term lock lubricant. It’s a light oil that goes tacky over time and collects dust and grit deep inside the mechanism — which is exactly what you don’t want. Use it once to free things up if you have to, then flush the mechanism and apply a proper dry lubricant. The WD-40 Specialist Dry PTFE Lubricant (a different product in the same brand range) is the better choice if you want to stay with WD-40.
What’s the best lubricant for UPVC windows and doors?
A dry lubricant designed for locks. Our professional preference is APECS Dry Lube. The most widely available alternative on the high street is WD-40 Specialist Anti-Friction Dry PTFE Lubricant, sold at Toolstation, Screwfix and Amazon. Both go on wet to flush the mechanism, then dry to a clean film that won’t attract dirt. Avoid sticky oils, grease, or anything petroleum-based for the lock itself.
How do I stop my UPVC door from sticking?
A sticking UPVC door is usually one of three things: the locking mechanism needs lubrication, the door has dropped on its hinges and is catching on the frame, or the seals have built up grime and are dragging. Start with a proper lubrication of the locking strip and a clean of the seals with warm soapy water. If the door has dropped, the hinges can usually be adjusted — most UPVC hinges have grub screws that allow vertical, horizontal, and compression adjustment. If lubrication and adjustment don’t fix it, the multipoint gearbox is likely on its way out and needs replacing.
Can I use grease on UPVC locks?
No — heavy greases attract dust and dirt and will eventually clog the mechanism, especially the cylinder. Stick to a purpose-made dry lubricant for locks. Light grease is sometimes used on the keeps (the slots in the frame that the bolts engage) but even there, dry lubricant tends to perform better long-term.
My UPVC door key turns but the door won’t unlock — is that a lubrication problem?
Almost certainly not. If the key turns freely but the bolts aren’t engaging or releasing, the multipoint gearbox has likely failed internally. Lubrication won’t fix this — it’s a mechanical replacement. The same applies if the handle lifts but the key won’t turn, which usually points to gearbox or cam failure. This is one to call a locksmith for rather than persisting.
