Double Glazed Sash Windows

Upgrading from single to double glazed sash windows

Most single glazed timber sash windows are cold and draughty in the winter and people naturally want to replace them with something better than plain modern plastic double glazed windows.

What’s The Process ?

To double glaze sash windows, we initially remove the sash beading and sashes themselves. which allows us to ascertain the sill’s condition, the box frame and external pointing. as if they’re in good enough condition an entire replacement is unnecessary. We then take measurements and recreate your new sashes, to match exactly or similar as per the customer’s needs all inline with current building regulations. Double glazed sash units are made up of two panes of glass with inert gas in-between which reduces heat loss because the gas is a poor conductor of heat.

Once the window has been fitted, we provide you with a full operational demonstration. We’ll advise you on the best way to look after your new double glazed sash windows to keep them looking their best for years to come.

Double Glazed Sash Windows in Conservation Areas 

Conservation areas have restrictions to ensure distinctive architectural features are preserved and that the property blends in beautifully with neighbourhood.

You may think double glazed sash windows can’t be installed in listed buildings, or in homes within conservation areas. But if you follow the correct initial application process combined with our exacting standards and attention to detail you could soon enjoy the benefits of better insulated windows combined with all their original characterful features.

If you’d like a quote for a bespoke double glazed sash windows contact us today.

London Sash Window Company
1432a Clock Tower Rd, Isleworth London TW7 6DT

“We’ve recently had 12 large sash windows fully refurbished and have been extremely impressed by the quality of the workmanship, attention to detail and customer service.”


Mr C Smith, London

Reviews Sash Windows
Sash Window Company in London - Accredited
London Sash Window Companies Approved
Replacement Sash Windows
Sash Window Company - TGAS Registered
Double Glazed Sash Windows London
Sash Window Repair

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