The sensitive replacement of traditional box sash windows is our speciality. Our unique collection includes the slimmest traditional box sash window available in the UK, as well as rarefied solutions for listed buildings and conservation areas.
Common throughout is an attention to proportion and accuracy of detail which allows us to faithfully replicate the simple grace of the original English box sash. Modern technology ensures that our sash windows will not warp or twist, require very little maintenance and provide 21st century standards of insulation and security.
More about our double-glazed sash windows
Sash windows have been in use in Britain for hundreds of years becoming very popular in the Georgian and Victorian period. They consist of one or more movable sections of window which slide over each other through the means of cords and counterweights. The extra weight of double glazed units made updating sash windows difficult, heavy wooden frames coupled with the double glazing meant that uPVC versions of sash windows became very popular. The other advantage of uPVC was the thermal insulation – we use simple yet effective insulation strips that eradicate the draughts and rattles associated with wooden windows. Using engineered timber allows for slimmer, lighter frames and modern versions of the cords and counterweights now allow for production of free moving timber windows – far superior in appearances to the uPVC versions.
Wood is a wonderful material in both appearances and strength, but with prolonged contact with water the moisture can cause warping, the movement of the warp goes in the direction of the grain. This characteristic has been used to create a highly durable and rigid material. By layering sections of wood with the grain laying in different directions it opposes any twisting or warping. This extremely strong engineered timber has been used for centuries in many countries for large structures such as bridges and churches, and is now used in Britain for manufacturing windows and doors.
Technology has made big differences to glass and glazing, modern advances guarantee high thermal insulation with little loss in natural light – light transmission is almost equal to clear glass whilst reducing heat transmission. Modern materials are used in spacer bars which result in low conductivity, reducing heat lost through the edges of the windows. These all add up to a high level of thermal efficiency, saving money by not wasting energy.
Another weak point in sash windows is the security aspect. The original sashes did not offer much protection against intruders and this is rectified with the use of internal mechanisms. This is combined with simple yet effective methods such as fitting the glass room-side so it can only be removed from the inside and ‘limit stops’ that restrict the sash opening too far.
For greater protection we use a paint system that requires minimal maintenance and yet provides an excellent level of protection – it comes in any of the RAL colours and can be matched to Farrow & Ball or Fired Earth colours to coordinate beautifully with your home.
These double-glazed sash windows are finished with catches and sash lifts from our range of window furniture, adding little touches in either modern or traditional finishes. Choose from brass – synonymous with the Victorian period, or contemporary chrome or brushed metal to match and embellish your new sash windows whilst matching your existing accessories.