Double Glazed Sash Windows
Double Glazed Sash London
Double Glazed Sash Surrey

Double Glazed Sashes Fitted to Existing Box Frames

Increasing Energy Efficiency

The purpose of our double glazed sashes fitted to the existing box frame & refurbishment service is to keep the original sash window box frame but to add new double glazed sashes fitted within the original box frame.

We also fit our brush-pile system which eradicates rattles and significantly reduces draughts in your sash windows.

Traditional sash windows often get painted shut or if they are not painted shut the build up of paint makes them hard to open and close, when we combine the new double glazed sashes with our Refurbishment service it resolves these issues and adds the element of double glazing without having to remove the main part of the box frame from the wall.

Call us on: 020 8395 1916

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Sash Windows Explained

Box Frames Explained

Double Glazed Fitted


  1. Before any works are carried out our team will lay dust sheets to the floor area and cover furniture with plastic sheeting.
  1. We start by removing the existing Staff Bead. (The Staff Bead is the beading on the interior of the window that holds in the lower sash)
  1. The lower sash can now be removed and disposed of.
  1. With the lower sash out the existing Parting Bead is now removed on both side of the box frame. (The parting bead is the thin strip of beading that runs vertically between the two sashes to stop them binding on each other)
  1. Now the upper sash can be removed and disposed of.
  1. With both the upper / lower sashes and beading removed we are able to access the weight pockets and take out the original sash weights.
  1. The original sash weights are now removed.
  1. At this point before we re-cord and refit the sashes we can offer our Optional inner box frame burn off service. Most sash windows are more than a hundred years old and will have over a hundred years of paint built up in the channels where the sashes run up and down, we offer a service to burn off the inner part of the box frame where the sashes run and give two coats of primer, although this option is not always necessary we highly recommend it to help the sashes run smoother.
  1. Now we re-cord the window using our high strength braided sash cord and new heavier weights to accommodate the new double glazed sashes are supplied and fitted
  1. The upper sash is hung and the new cord is attached with screws to give a secure fixing.
  1. The new parting beads are fitted with our brush-pile draught proofing system and fitted to the box frame, an additional length of parting bead is fitted to the head of the box frame to stop draughts coming through from the head of the frame.
  1. The new double glazed lower sash has an 8mm rebate routed in to its meeting rail to accept our brush-pile system to draught proof the gap where the upper and lower sashes meet in the middle when closed.
  1. The lower sash is hung and the new cord is attached with screws to give a secure fixing.
  1. The new staff beads that contain our brush-pile draught proofing system are cut to fit the box frame and are secured with lost head brads.
  1. The staff and parting beads are now sealed with sealant.
  1. New ironmongery consisting of two sash lifts and one Brighton fastener are fitted to your window in a choice of Polished Brass, Polished Chrome or Satin Chrome finishes as standard.
  1. The old staff and parting beads and any other rubbish are taken away by our team.
  1. The dust sheets are removed and the floor is hoovered by our team

Double glazed sashes fitted to existing box frames



NOTE: No painting or preparation for painting is included in this service, all painting is to be done by the customers own contractor

Sash Double Glazing

Fitting double glazed sashes paired with our refurbishment and draught proofing service dramatically increases the energy efficiency of you sash windows and has the added benefit of increased noise reduction.

If noise is a particular problem we can incorporate acoustic glass into your new double glazed sashes.

If privacy is an issue we can incorporate obscure glass into your new double glazed sashes.

We have a solution to all of your sash window needs.

Please have a look at our new double glazed sashes and refurbishment specification.

If you would like to talk through any of our options please feel free to call on 020 8395 1916 or use our contact form


Free Sash Window Quotations

Novells Of Surrey & London are a FENSA registered company and offer an insurance backed guarantee supplied by the glass and glazing federation insurance scheme.

We offer a free consultation where we can discuss the best option for your windows. Once the customer instructs us to carry out the work we conduct a full survey making sure that the specifications are to your exact requirements.

Once the sash windows have been made one of our highly skilled craftsmen will install the windows taking the utmost care to cause the minimum disruption, we are fully aware that this is your home and we will treat it with the respect it deserves.

Philip Novell – Owner, Novells Of Surrey & London

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Fensa® Registered

FENSA works with thousands of double glazing companies in England and Wales as the market leading Competent Person Scheme (CPS) for the glazing industry.