Thu Aug 27
A well-built timber window lasts 60 years or more, and plenty of Georgian and Victorian sashes are still doing their job today.
What determines that lifespan comes down to four things: the species of wood, the quality of the finish, how well it was fitted, and how often it’s been maintained since.
TRC Contracts manufactures timber windows to a 60-year service life, backed by a 10-year guarantee on materials and workmanship. Here’s what shapes that lifespan in practice, how timber stacks up against uPVC and aluminium, and what keeps a window performing decades on.
How long do timber windows last?
Specified correctly and looked after, most quality timber windows last somewhere between 60 and 100 years. Plenty of Georgian, Victorian and Edwardian buildings still have their original sash windows in place, which says more about a well-made timber frame than any specification sheet could, as TRC’s guide to maintaining sash windows sets out.
What affects how long timber windows last
Timber species and treatment
TRC’s engineered frames use redwood, hardwood, Accoya or oak, each factory finished with a three-coat microporous paint or stain.
Paint and finish
Paint isn’t decoration, it’s the barrier keeping moisture out of the timber. TRC’s guide to painting timber windows puts properly protected timber at 9 to 14% moisture content, with dry rot risk starting past 20%.
Installation quality
Fit a window with the right tolerances and weathertight seals and it sheds water as designed. Get the fitting wrong and even the best frame won’t last as long as it should.
Regular maintenance
Cleaning, repainting and checking seals on schedule is what turns a good specification into a window still earning its keep decades later, a point we cover in our piece on window maintenance and longevity.
How timber compares with uPVC and aluminium
Timber’s real edge over uPVC and aluminium is that it can be repaired. As TRC’s comparison of timber and aluminium windows explains, a timber frame can be repaired and refinished again and again, stretching its service life about as far as you’re willing to take it. uPVC and aluminium don’t offer that flexibility, so once a seal or section fails, replacement is usually the only option left.
How TRC windows are built to last
Every TRC window comes with a published warranty, set out on the care, maintenance and warranty page:
| Element | Warranty period |
| Manufacturing and material defects | 10 years |
| Factory paint finish | 10 years |
| Double glazed sealed units | 10 years |
| Slim double glazed units | 7 years |
| Vacuum glazing | 20 years |
| Ironmongery | 5 years |
Every installation comes with a maintenance and care manual too, and architects specifying early can get technical support through TRC Consult.
Signs your timber windows need attention
TRC’s guide to timber rot repair flags what to watch for: soft or spongy timber, darkened patches, flaking paint, and gaps opening in the glazing putty. Catch these early and it’s usually a repair job, not a full replacement.
How to extend the life of your timber windows
Repaint every 5 to 7 years, keep an eye on moisture content, and clear debris from sills so water can drain away. Lubricate the moving parts on sash and casement mechanisms, and deal with failed putty as soon as you spot it rather than leaving it through winter.
Frequently asked questions
Can rotten timber windows be repaired instead of replaced?
Usually, yes. Localised wet or dry rot in a sill or rail can be cut out and repaired with epoxy resin systems, as covered in TRC’s timber rot repair guide. Full replacement only comes into it once structural sections have failed extensively.
Do timber windows need more maintenance than uPVC or aluminium?
A bit more, yes, but that extra attention buys a longer lifespan and the option to repair rather than replace.
What warranty comes with TRC timber windows?
Manufacturing defects and the factory paint finish are covered for 10 years, double glazed units for 10 years, and vacuum glazing for 20 years, detailed on the care, maintenance and warranty page.
Specifying timber windows for a project and want to talk through species, finish or warranty terms? Contact TRC Contracts.
