--- title: How to Fix a Sticking uPVC Window description: "How to fix a uPVC window that is sticking: clean and lubricate the hinges and hardware, and spot when a stiff sash means a dropped window needing adjustment." --- [![SM\_Logo\_Final\_Lught](https://smwindowsanddoors.co.uk/hs-fs/hubfs/SM_Logo_Final_Lught.webp?width=140&height=80&name=SM_Logo_Final_Lught.webp "SM_Logo_Final_Lught")](https://smwindowsanddoors.co.uk) - About - [About](https://smwindowsanddoors.co.uk/about) - Doors - [uPVC Doors](https://smwindowsanddoors.co.uk/upvc-doors-york) - [Sliding & Bifold Doors](https://smwindowsanddoors.co.uk/aluminium-sliding-bi-fold-doors) - [Composite Doors](https://smwindowsanddoors.co.uk/composite-doors-york) - [Heritage Aluminium Doors](https://smwindowsanddoors.co.uk/heritage-aluminium-windows-doors) - [Door Repairs](https://smwindowsanddoors.co.uk/window-door-repairs-york) - Windows - [uPVC Windows](https://smwindowsanddoors.co.uk/upvc-windows-york) - [Casement Windows](https://smwindowsanddoors.co.uk/casement-windows-york) - [Sash Windows](https://smwindowsanddoors.co.uk/sash-windows-york) - [Timber Windows](https://smwindowsanddoors.co.uk/timber-windows-york) - [Heritage Aluminium Windows](https://smwindowsanddoors.co.uk/heritage-aluminium-windows-doors) - [Lanterns & Roof Lights](https://smwindowsanddoors.co.uk/korniche-lanterns-flat-roof-lights) - [Window Repairs](https://smwindowsanddoors.co.uk/window-door-repairs-york) - Conservatories - [Conservatories](https://smwindowsanddoors.co.uk/conservatories-orangeries-york) - [Orangeries](https://smwindowsanddoors.co.uk/conservatories-orangeries-york) - Resources - [Gallery](https://smwindowsanddoors.co.uk/gallery) - [Brochures](https://smwindowsanddoors.co.uk/brochure-downloads) - [Blog](https://smwindowsanddoors.co.uk/blog) - [Reviews](https://smwindowsanddoors.co.uk/customer-reviews) - [Contact Us](https://smwindowsanddoors.co.uk/contact) [Request A Quote](https://smwindowsanddoors.co.uk/request-a-quote) [![SM\_Logo\_Final\_Lught](https://smwindowsanddoors.co.uk/hs-fs/hubfs/SM_Logo_Final_Lught.webp?width=140&height=80&name=SM_Logo_Final_Lught.webp "SM_Logo_Final_Lught")](https://smwindowsanddoors.co.uk) [Request A Quote](https://smwindowsanddoors.co.uk/request-a-quote) - About - [About](https://smwindowsanddoors.co.uk/about) - Doors - [uPVC Doors](https://smwindowsanddoors.co.uk/upvc-doors-york) - [Sliding & Bifold Doors](https://smwindowsanddoors.co.uk/aluminium-sliding-bi-fold-doors) - [Composite Doors](https://smwindowsanddoors.co.uk/composite-doors-york) - [Heritage Aluminium Doors](https://smwindowsanddoors.co.uk/heritage-aluminium-windows-doors) - [Door Repairs](https://smwindowsanddoors.co.uk/window-door-repairs-york) - Windows - [uPVC Windows](https://smwindowsanddoors.co.uk/upvc-windows-york) - [Casement Windows](https://smwindowsanddoors.co.uk/casement-windows-york) - [Sash Windows](https://smwindowsanddoors.co.uk/sash-windows-york) - [Timber Windows](https://smwindowsanddoors.co.uk/timber-windows-york) - [Heritage Aluminium Windows](https://smwindowsanddoors.co.uk/heritage-aluminium-windows-doors) - [Lanterns & Roof Lights](https://smwindowsanddoors.co.uk/korniche-lanterns-flat-roof-lights) - [Window Repairs](https://smwindowsanddoors.co.uk/window-door-repairs-york) - Conservatories - [Conservatories](https://smwindowsanddoors.co.uk/conservatories-orangeries-york) - [Orangeries](https://smwindowsanddoors.co.uk/conservatories-orangeries-york) - Resources - [Gallery](https://smwindowsanddoors.co.uk/gallery) - [Brochures](https://smwindowsanddoors.co.uk/brochure-downloads) - [Blog](https://smwindowsanddoors.co.uk/blog) - [Reviews](https://smwindowsanddoors.co.uk/customer-reviews) - [Contact Us](https://smwindowsanddoors.co.uk/contact) [Repairs & Maintenance](https://smwindowsanddoors.co.uk/blog/tag/repairs-maintenance) # How to Fix a Sticking uPVC Window By [SM Windows & Doors](https://smwindowsanddoors.co.uk/blog/author/sm-windows-doors) Nov 5, 2026, 2:30:00 PM 3 Minutes Read A window that fights you every time you open it is a small annoyance that gets old fast. To fix a uPVC window that is sticking, you usually only need to clean and lubricate the moving parts, and once you know the routine it takes a few minutes per window. Here is what makes a uPVC window stick, how to free it off, and how to tell the difference between a bit of grime and a sash that has dropped and needs adjusting. ## Why uPVC windows start to stick Most sticking comes down to dirt and dry hardware rather than anything broken. The hinges, the locking points and the friction stays all move against each other every time you open the window, and over the years they collect dust, grit and grime. Add a bit of Yorkshire damp and the moving parts stiffen up. The other common cause is a sash that has dropped slightly under its own weight, so it rubs on the frame instead of swinging free. Working out which one you have got is the first step. ## Clean the frame and hardware Start simple. Open the window fully and have a good look at the hinges and the channel the sash sits in. - Wipe the frame and the hinge track with warm soapy water and a cloth. - Use an old toothbrush to work grit out of the hinge arms and the friction stay. - Clear anything caught in the drainage slots along the bottom of the frame. You would be surprised how often a proper clean alone frees a sticking window. Grit in the hinge track is the number one culprit. ## Lubricate the moving parts Once everything is clean and dry, lubricate the parts that move: - A light **silicone spray** or a spot of light machine oil on the hinge arms and pivot points. - A dab on the locking cams and keeps around the sash edge. - Work the handle and swing the window a few times to spread it. Avoid thick grease or general purpose sprays that attract dust, and keep oil off the rubber seals. Silicone is kinder to both the seals and the plastic. Wipe away any excess so it does not run. ## Check the handle and locking mechanism If the window opens fine but the handle is stiff or will not turn, the espagnolette (the locking bar running around the sash) may be dry or slightly out of line. A little lubricant along the locking points usually frees it. If the handle spins loose or feels like something has snapped inside, the mechanism has likely failed and needs replacing, which is a straightforward part swap for a repairer. ## When a sticking window means a dropped sash Here is the difference that matters. If the window is clean and lubricated but still rubs, particularly catching on one corner of the frame, the sash has probably dropped. A uPVC sash is heavy, and over time it can settle out of square so the glass no longer sits centred in the frame. You can often see it: close the window and look at the gap around the sash. If it is tight in one corner and wide in the opposite one, the sash needs realigning. On many uPVC windows this is corrected by adjusting the glass packers, sometimes called toe and heeling, which resets the sash square in the frame. It is fiddly and best done by a glazier, because getting it wrong can crack the seal or the glass. Our [window repair team](https://smwindowsanddoors.co.uk/window-door-repairs-york) handles dropped sashes across York, and can rehang or adjust the window properly. ## Keeping windows moving freely A twice yearly clean and lubricate keeps uPVC windows opening smoothly for years. Wipe the frames and hinges, clear the drainage slots, and give the hardware a light oil. If a window keeps sticking despite all that, or the trouble is a worn hinge rather than grime, it is worth getting it looked at before the sash drops further. If yours are old and past their best across the board, our [uPVC window range](https://smwindowsanddoors.co.uk/upvc-windows-york) shows what a smooth, well hung replacement looks like. ## FAQs ### What is the best lubricant for sticking uPVC windows? A light silicone spray is ideal, as it frees the hinges and locking points without attracting dust and is kind to the rubber seals. A spot of light machine oil works on the metal hinge arms too. Avoid thick grease and general purpose sprays, and keep oil off the seals. ### Why does my uPVC window stick when it was fine before? Usually grit and grime have built up in the hinge track and the hardware has dried out, which stiffens everything up. A clean and a light lubricate normally sorts it. If it still rubs after that, the sash may have dropped slightly and need realigning. ### Can I fix a dropped uPVC window sash myself? You can clean and lubricate it yourself, but realigning a dropped sash by adjusting the glass packers is fiddly and best left to a glazier. Getting the packing wrong can strain the sealed unit or crack the glass, so it is worth having a repairer reset it properly. ### How often should I lubricate my uPVC windows? Twice a year is a good rule, along with a clean of the frames and hinge tracks and clearing the drainage slots. Regular upkeep stops the hardware seizing and helps prevent the sash dropping, which keeps the windows opening smoothly for years. Want to see the full range of styles and finishes? [Download our latest brochure](https://smwindowsanddoors.co.uk/brochure-downloads), or [request a free quote](https://smwindowsanddoors.co.uk/request-a-quote) and we will pop out for a look. #### SM Windows & Doors Author ## Phone: 07833387823 Email: [Sam@smwindowsanddoors.co.uk](mailto:Sam@smwindowsanddoors.co.uk) Opening times: Mon - Fri: 09:00 - 17:00 Sat-Sun: By Prior Appointment [Follow us on Facebook](https://www.facebook.com/people/SM-Windows-Doors/100093013267883/) [Follow us on Instagram](https://www.instagram.com/smwindowsanddoors/) ![x59dcc190ea7d320001f0083a\_logoAsset-2-1.jpg.pagespeed.ic.lk8k-280iY](https://smwindowsanddoors.co.uk/hs-fs/hubfs/x59dcc190ea7d320001f0083a_logoAsset-2-1.jpg.pagespeed.ic.lk8k-280iY.jpg?width=300&height=106&name=x59dcc190ea7d320001f0083a_logoAsset-2-1.jpg.pagespeed.ic.lk8k-280iY.jpg "x59dcc190ea7d320001f0083a_logoAsset-2-1.jpg.pagespeed.ic.lk8k-280iY") ```json { "@context" : "https://schema.org", "@type" : "BlogPosting", "author" : { "@type" : "Person", "name" : "SM Windows & Doors", "url" : "https://smwindowsanddoors.co.uk/blog/author/sm-windows-doors" }, "dateModified" : "2026-11-05T14:30:00.547Z", "datePublished" : "2026-11-05T14:30:00.000Z", "headline" : "How to Fix a Sticking uPVC Window", "mainEntityOfPage" : { "@id" : "https://smwindowsanddoors.co.uk/blog/sm-windows-doors-blog/how-to-fix-a-sticking-upvc-window", "@type" : "WebPage" }, "publisher" : { "@type" : "Organization", "logo" : { "@type" : "ImageObject", "url" : "https://smwindowsanddoors.co.uk/hubfs/SM_Logo_Final_Lught.webp" }, "name" : "SM Windows & Doors" } } ```