Sash windows

Double Glazed Box Sash Windows

The double hung sliding sash window was introduced to the UK in the 17th Century, Christopher Wren was an early proponent of this style and it featured heavily in his plans to rebuild the capital following the Great Fire of London.
Glazing bars were a common device in pre-Victorian architecture, in many ways Georgian and Regency styles are synonymous with this feature. The reason for their inclusion was not however, to add visual interest to the property‘s elevation, the truth is much more prosaic. Before glass manufacturing technology advanced sufficiently to allow the production of large panes, the maximum size of a pane was determined by the lung capacity of the glass-blower.
The material of choice for the majority of parts was traditionally slow-grown Baltic softwood with, in better quality work, hardwood specified for the cill portions.
Bringing sash window design into the 21st Century, your windows can be produced to be as authentic as possible to their original counterparts but with much more efficient and advanced technologies.
Double glazed box sash windows are provided with weights and cords to hold it in a place in any opening position: the sash weight is connected to the window frame by a chain (metal) or cord (nylon or cotton/hemp or other material) that runs over the Pully at the top of the frame. Sash chain might be selected to negate the requirement for cord replacement and also better handle the increased weight of the sashes – a long-term investment.
Furthermore, the weight of modern double glazing packages is considerably greater than the original 3 or 4 mm thick float glass and might require, on some windows, a weight enhancement using Lead weights instead of Steel weights.
The trickle ventilation to be machined into the frames is not recommended. This feature is intrinsic to the design and the application of plastic vent covers devalues the integrity of the product. There are many ways to provide alternative ventilation, your architect or building contractor should be able to guide you through this.
In conclusion, the box frame is most ideal for town and city living. Unlike casement (hinged) styles of window, the sashes of a box frame do not impede traffic passing by when they are open, they can be securely locked and their proportions are extremely variable, making them suitable for almost every size of opening.

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  • Reply Michael September 25, 2016 at 12:44 pm

    Hello, I have French Doors in my house that need repair.
    Are you able to come to Muswell Hill, London N10 to look and quote?


    Michael M 07970875441

    • Reply admin April 16, 2022 at 12:16 pm

      Hi Michael,
      Thanks for your comment.
      At the moment we do focus on manufacture of beautiful new Sash Windows.

      Thank you!

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