How often should windows be replaced?

Replacing an old window frame

Most professional window installers will agree that a newly installed, good-quality window should last at least 20 years before it needs repairing or replacing. Many companies that manufacture uPVC windows provide a 20 to 25-year warranty, which is essentially the product's expected lifetime. A 10-year guarantee is not uncommon for a timber-framed window.
After 15 years of regular use, a window of any material often needs repair work. The main issues are insulation breakdown, weatherproofing deterioration and caulking degeneration. Temporary fixes are fine, but they will only last a short time, and eventually, you will need to consider a complete window replacement.
There are many options to consider when replacing windows. One of the most pressing is the balance between cost and benefits. Higher-quality windows may cost more upfront, but the benefits are felt down the line, as they will operate more efficiently, require less maintenance, and last much longer.
The window material is a significant factor in how long it will last. Quality uPVC windows are known for their strength and longevity, as are aluminium patio windows. Hardwood timber windows need more maintenance but can also have long lifetimes.
Other considerations for homeowners are energy cost savings from better insulation and improved comfort. Here are some tell-tale signs that it's time to replace your windows.

Cracks in the frame

Windows are permanently exposed to the elements, so seeing some wear and tear after a few years is unsurprising. A cracked window frame is not just unattractive; it can compromise insulation, allow water to penetrate and cause problems that extend well beyond the frame. Minor scratches and scuffs should not worry you unduly; marks can usually be removed with a wipe clean. However, cracks and splits are much more serious as they can attract dampness and mould, which may undermine the frame's fabric.

Draughty windows

The first sign of trouble is draughts of cold air that are felt when the window is tightly closed.
Sealants can degrade over time, and weatherproof seals can degenerate. If you can feel draughty air around the frame, it probably means the seals have failed or are no longer working correctly. Well-functioning windows should not let in any air at all except through specialised vents or when they are deliberately open. Sealants will provide a quick DIY fix but rarely last long.

Window pane condensation

Fogged-up windows are a common problem with double-glazed and triple-glazed windows. Water gets trapped between the glass panels, usually from tiny holes too small to see. With panels filled with inert gas, condensation is often a sign that the gas has leaked out. Either way, the glass panels are not keeping your home as warm as they should be, and the panels, or even the whole window, should be replaced.

Windows getting stuck

Windows that are difficult to open and close can be particularly annoying. Repeated opening and closing of windows puts stress on the frame. If the windows are shutting by themselves or sticking when closed and proving difficult to open, it's time to consider a replacement. Sticking is a sure sign that a window is showing its age.

Higher energy bills

It's estimated that around 40% of annual household expenditure goes towards heating and ventilating the average home. If you notice your energy bills increasing monthly, it's worth checking to see if draughty windows are the problem. Replacing old and weatherworn windows with energy-certified products can result in substantial savings on overall energy costs for the home.

Fading home furnishings

Modern windows can be fitted with glass that provides protection against damaging UV light. This is part of the light spectrum that can 'bleach' out furniture and carpets with subsequent fading and loss of colour. A window replacement that includes UV protection can end this problem.

More on windows

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