Sliding Box Sash Timber Windows
Our vertical sliding box sash timber windows have been designed to replicate the simplicity and elegance of the original sash window, which dates as far back as the 17th Century, where they were fitted into the elegant houses of that time. Today they are widely seen in Georgian, Edwardian and Victorian period properties in many areas across the country, as well as in many new builds, giving a classical look to a more modern property.
Some say that they were first invented by the French before then being introduced to Britain via Holland, although more recent research shows the sliding box sash to have been invented here in the United Kingdom. When, where, and by whom is not really of importance when it comes to the increased need for performance and security of this classical timber window, with weather-sealing and thermal efficiency becoming more and more necessary. It is paramount that we modernise this classic, bringing it up to the level of specification required in the 21st Century, with improved glazing, weather-sealing and security.
The TimberPlus sliding box sash can be made using traditional lead weights and pulleys, or adapted to take spiral balances, which we fit into the sashes themselves, as opposed to the frame as is often found, meaning that you don’t have to compromise on the classic look, whilst saving on price. The spiral balance is becoming more and more popular around the country, although many conservation and planning departments do not allow them.
These handcrafted windows are made from the highest quality sustainable timbers. We only purchase timber from suppliers who offer FSC (Forest Stewardship Council) or PEFC (Programme for the Endorsement of Forest Certification) certified products. We also insist on using completely solid timber (not engineered or veneered components). Whilst we are able to offerany timber legally available in this country, we predominantly use Sapele hardwood, with its fine-knit grain giving good durability for external joinery use; and joinery grade European redwood, which has fewer knots than some lesser grades of softwood.
Originally, cast iron or steel weights were used with brass pulleys, but due to the added weight of both single and double glazing nowadays, a heavier weight is needed, so to avoid oversized timber casing to take these, lead is now more commonly used. Lead is not only heavier, but also less brittle, meaning it will withstand the test of time more easily.
Our sliding box sashes are manufactured to the highest standards, always ensuring a good fit of the sashes in the frame as well as complete accuracy of balancing, to give you the ability to slide them easily with a single finger.
Staff beads are fitted externally as standard to give a rebate, but decorative horns are not, so please let us know if you need to have these. A high performance weatherseal is used as standard, as well as soft-coat low E double glazed units filled with argon for added thermal efficiency.
As standard we supply locking fitch fasteners on our sliding box sashes, in a choice of finishes. Should additional security features be required, we can supply various designs of lock on request.
At TimberPlus, we are so confident in the quality of finish of all our joinery items, that we don’t feel the need to ‘cover-up’ our workmanship with a paint or stain finish. We therefore, leave all of our items in the raw timber state as standard, whether they be in hardwood or softwood. That said, we also understand that some of you would prefer to leave the finishing to experts, which is why we are able to offer you a range of finishes from just priming through to full factory spray finish and factory glazing in your choice of colour(s) as an added extra, giving you peace of mind that all you are left to do is fix the window in place. Please note: if you are upgrading to a full factory finish including pre-glazing, we advise you to make sure this will not cause difficulty when it comes to fitting yourwindows (see our guide on installing timber windows).