Box Sash Windows

The “Box” or “Case” which is sometimes referred to is the casing at the sides (and sometimes top) of a sliding sash window frame. These would traditionally house lead weights, attached to the opening sashes by cords or chains via pulleys in order to balance the weight of the sash and allow it to be left in any position when opened. With modern frames, other methods of balancing the sashes are often used, such as the spring balances which we use in our sash windows. These modern balances are constructed from two counter-spiralling springs within a tube, arranged in such a way that the overall force exerted by the springs to pull the sash upwards is near-constant for the full range of extension of the spring. This means that the springs effectively “balance” the weight of the opening sash for its full range of movement, as if a counterweight were used, unlike a simple coil spring which would “pull harder” the more it is extended, making it unsuitable for use in sash windows. The size of casing needed to house the lead weights fitted to traditional box sash windows meant that the windows would usually be fitted into a reveal, i.e. with part of the frameset behind the brickwork of the building. This means that the window would effectively have to intrude into the inside space of a room. Spring balances take up much less space than lead balance weights, and as a result, we can now make windows with much narrower frame components, designed to be fitted into a standard brickwork cavity in much the same way as hinged casement windows. These thinner frames mean that you can maximise the glass area within a given opening size, letting as much light in as possible. Spring balances and their frames are also generally more cost-effective than lead weights and the large timber frames needed to house them, making them very competitive on price – even competitive with softwood and uPVC windows in many cases. Please contact us for a quotation today! If you are interested in our window products or would like a free quotation, please fill out our callback request form, or call us on 0333 335 5416.

Windows & Doors UK have experienced designers who can help you with the design and style aspects of your box sash windows. From frame style to woodwork, from ironmongery options through to installation our designers can assist. CAD drawings are produced outlining the windows dimensions, design and functionality aspects.

Decorative ironmongery for windows can play an important part in the overall look of new timber windows and doors. We source and provide a range of ironmongery options for windows and doors that complement the overall look and feel of the product. From traditional to victorian, from modern to contemporary styles, you choose the handle style that fits your preference and we’ll ensure your windows and doors come supplied. Download Ironmongery Options PDF

If you are looking to replicate an existing window style for your new hardwood windows then please give us a call on 0333 335 5416 to discuss your replica window requirements. Some historic windows can (depending on age) be hard to find parts for, or may well be beyond economical repair, at which point, replica windows are ideal to replace with ‘a like for like’ style with new materials and parts.

Windows & Doors UK make ordering a straightforward process. Once you have chosen your window/door product and have agreed the drawings/specifications and design, the product will be scheduled for manufacture. Your products will be delivered by a scheduled date through recorded delivery.