Double Glazed Sash Windows

Replace Existing Glass With Slim Double Glazing

Our sash window double glazing upgrade service is designed to radically improve your original sash and case windows and make them energy efficient.

Eco Sash & Case supply the latest energy-efficient double glazing on the market today, at competitive prices. We can insert your choice of double glazing into the original sash windows and fully restore the sash window. Your windows are then painted and finished with traditional sand mastic.
sash window restoration

Energy-Efficient Slim-Fit Double-Glazed Upgrade

A typical sash window double glaze upgrade involves:

  • Remove original window glass
  • Replace any rotten timber and restore original sash casement
  • Install slim 12mm argon gas filled double glazing
  • Fully painted with 3 coats of exterior grade paints
  • Replace external pointing with traditional sand mastic
  • New sash ropes and pulley wheels
  • Energy-efficient draught proofing
  • Brighton sash locks and ironmongery

Book your free, no-obligation Eco Windows Survey.

Brochures and Listed Building Advice

If you own a listed building, you will need to obtain listed building consent. You can download more information on obtaining planning permissions and listed building advice, or contact our office staff for step‐by‐step guidance on the process.

At Eco Sash & Case, we’ve been working on listed buildings for many years so are perfectly placed to provide you with advice.

Bespoke, handmade sash windows crafted in our Edinburgh workshop
draught proof sash windows in Edinburgh
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Save On Your Heating Bills

Our double glazed sash window upgrade will radically improve your original windows and make them energy-efficient, and save you money on your heating bills.

How we offset our carbon footprint

Planting Scots Pine Trees

We’ll plant a Scots pine through Trees for Life for every completed sash window project over £5000.

Trees for Life is an award-winning Scottish charity working to restore Scotland’s Caledonian Forest.

Book your free, no-obligation Eco Windows Survey.

Clearer Views

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Need to upgrade your windows with double glazing?

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The Homeowners’ Guide to Repairing and Replacing Sash & Case Windows, Sustainably
The Homeowners’ Guide to Repairing and Replacing Sash & Case Windows, Sustainably

To get your FREE guide with help and advice from our Eco Sash & Case experts simply fill in your details below and we’ll email it straight to you!


Get in touch

Contact us now and our experienced team will arrange a time and date to survey your windows, answer your questions and see how we can help you.

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