A window that's become a struggle to open is rarely broken beyond repair — usually it just needs cleaning, adjusting or lubricating.
Casement windows have a channel around the frame where the sash seats when closed, and over time this collects dust, dirt and, near ground level, garden debris, all of which increases friction when opening. A thorough clean of the frame channel and the visible parts of the hinge mechanism resolves a surprising number of stiff windows without any parts needed.
The hinges and locking mechanism inside a uPVC window are metal components that need periodic lubrication to move freely. Without it, they gradually stiffen, particularly in windows that are opened infrequently. A light silicone-based spray applied to the hinges and visible mechanism, twice a year, keeps movement smooth and prevents premature wear.
As with doors, window sashes can drop very slightly on their hinges over years of use, causing the sash to catch against the frame at one point in its opening arc. This produces a stiff, uneven feel to opening rather than a uniformly heavy action, and is fixed by a hinge adjustment rather than lubrication alone.
uPVC expands slightly in very hot weather, and a window that opens fine in winter can become noticeably stiffer on a hot summer day as the frame and sash expand marginally into each other. This is usually a minor, temporary effect, but if it's pronounced it may indicate the window was fitted with insufficient clearance originally.
If a window has become progressively stiffer over months rather than suddenly, and cleaning and lubrication haven't helped, it's worth having a fitter check for frame distortion, particularly on older installations or where nearby building work may have affected the surrounding wall. In rare cases this points to the window needing to be re-set or replaced.
The most common causes are debris in the frame channel or a lack of lubrication in the hinges, both of which are simple to fix. A sudden change is less likely to indicate a serious structural issue than a gradual worsening over months.
A light silicone-based spray is best for uPVC window hinges and mechanisms — avoid heavy oils, which attract dust and can actually make the problem worse over time.
Not usually — most stiffness is resolved with cleaning, lubrication or a hinge adjustment. Replacement is only worth considering if stiffness is combined with visible frame damage or distortion.
Yes, uPVC frames expand slightly in high heat, which can make a window noticeably stiffer on hot days even if it opens easily the rest of the year. This is usually a minor, temporary effect.
A window that sags, won't stay open, or feels loose on its hinge is a common and usually inexpensive fix.
A window that won't lock is a security risk — most causes are mechanical and fixable without replacing the whole unit.
A sash window that won't slide is usually down to paint, swelling or worn cords — rarely the sash itself.
Black mould on window frames is a moisture problem, not a cleaning problem — here's how to find the real cause.
A snapped door handle is one of the most common uPVC door faults — and one of the quickest to fix correctly.
A door that scrapes the frame or is hard to lock hasn't broken — it has simply dropped, and it can usually be adjusted back.
Contact us for advice on freeing up a stiff window, or book a free survey if it's time to consider replacement.
