How Long Do Timber Sash Windows Last?

If you’re looking into buying timber sash windows then this question will be right at the top of your list. With the availability of beautiful PVC-U sash windows which are aesthetically almost indistinguishable from authentic timber counterparts, you’d be justified in asking yourself ‘are timer windows actually worth the money?’ Well many experts in the field firmly believe that they are, as they can provide many years of beauty and functionality for your home. Of course, just how long they last for depends entirely on the following factors –

Quality of Timber

You may not know the difference to look at, but in terms of longevity, different standards of wood have different life spans. It has been said that, as a rule, softwood which has been grown quickly for Double Glazing Sash Windows Kent maximum profit tends to be weaker and more susceptible to decay and rot than slow grown hardwoods sourced through the official channels. Whilst this can be true of illegally sourced softwood timber, it’s not always the case.

That’s because the only softwood used to create the very best sashes is European Redwood which has been produced in accordance with the Forestry Stewardship Council’s (FSC) ‘Chain of Custody’ programme, which tracks, monitors and accredits legal logging worldwide. This means it’s a quality product which will last.

Remember that modern window manufacturers also use high quality hardwoods for sash window construction, wherever required.


If untreated timber comes into contact with a moisture level of 21% or more, then it will begin to absorb water at an alarming rate. This opens timber frames up to rot and insect infestation, which will greatly reduce their lifespan.

Thankfully, preservation techniques can help; the best consist primarily of treatment with Boron wood preservative -a naturally occurring product which is so effective that some companies provide a 30 year guarantee against rot and fungal damage for sashes treated with it! The solution allows the wood to breathe whilst repelling the elements, ensuring that wood looks great throughout its life.