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Full sash window restoration

Remember how good your windows used to look? Well we can fully restore your original timber sash windows back to their former glory. As well as fully draught-proofing the windows, we get them working properly again. We will also completely and sympathetically restore the windows, so they look like new without losing any original features. It’s a complete repair and restoration which involves the whole window.

sash window before renovation

Is this for you?

  • Do your windows look old and tired?
  • Do you want to to keep the originals?
  • Are the windows or sills rotten?
  • Do your windows feel noisy and cold?
  • Do they rattle?
  • Do they need repairing?
Sash window paint


  • Sympathetically restored sash windows back to their former glory.
  • They will look like new and they will open and close smoothly.
  • As part of this service the sash windows are fully draught-proofed.
  • Your rooms will feel warmer.
  • Soundproofing will be enhanced.
  • Enjoy beautiful looking windows again. 
Refurbished Sash

How do we do it?

We take out the timber sashes and take them off-site to our workshop in Twickenham. At our workshop, we strip sashes back to wood, we rebuild the joints, the glass is cleaned and re-sealed into the frames, rot repairs are carried out, then the sashes are primed, undercoated and two finish coats are applied using paint from The Little Green Paint Company. 

On-site we restore the sash boxes by stripping back to wood, rot repairs are carried out, and new hardwood cills are installed, if required. The boxes are then painted to finish coat. 

Once the sashes and sash boxes are restored, then the sashes are re-installed incorporating a draught-proofing system and new waxed cotton sash cords. 

Finally, new sash window furniture and locks are fitted. This process takes approx. one week. During this time the windows will be boarded up with security boards when we are not on site.

Restoration case studies

Nestled amidst historical architecture and charming landscapes of Teddington, this sash window renovation project took place, bringing new life to ten elegant windows.

This amazing house in Teddington, South West London had its windows restored to their former glory by SashWise. Read all about it here.

See photos of this new sash and double-glazed casement window project in Isleworth by SashWise.

See photos of this new double-glazed sash window project in East Twickenham by SashWise.

This project was a refurbishment of existing sash windows in a Victorian property in Wimbledon.

See photos of the full restoration of sash windows on a Victorian house in Teddington.

Full-house sash window restoration project in Chertsey, Surrey, keeping the original features of the building and its windows.

We installed new Accoya double glazed sashes into five windows into this lovely Teddington property. Increasing thermal performance and insulation. Plus - no more rattles!

Full restoration – Chiswick

A full sash window refurbishment at a beautiful house in Chiswick. Renovation of two square bay windows and a large stained glass window.

SashWise fully restored the original sash windows in this stunning Victorian house in Mortlake.

SashWise fitted new Accoya double-glazed sash windows into the original sash boxes at this beautiful Edwardian detached townhouse in Hampton.

We installed 14 new hardwood double glazed sashes into this stunning Victorian house in Kingston.

The original sash windows had been removed from this beautiful Victorian cottage in Twickenham. Our client wanted the windows changed back to their original style.

We completely restored 20 original timber sash windows though out this gorgeous Victorian house in Richmond.

Our client completely restored the property and wanted to replace the windows with a more robust solution, keeping the original features in the windows.

We replaced the original single glazed windows in this beautiful Victorian House in Teddington with new hardwood double glazed sashes.

Our other services

Sash window draught proofing

Servicing and draught-proofing

If your sash windows have broken cords or are stiff or jammed shut then this service will restore them to their original smooth working order.

Georgian sash window

Sash window repair and restoration

We completely and sympathetically restore your windows, so they will look like new without losing any of their original features.

Hardwood double glazed sash windows

New hardwood double glazing

If you do not require complete window replacement we can make new double glazed timber sashes to fit your original box sash frames.

Victorian sash window

New hardwood sash boxes

We can supply and fit new hardwood sash boxes complete with double glazed sashes that exactly replicate your original windows.

Three reasons to restore your sash windows

Energy efficiency

Energy efficiency

Restoring sash windows can significantly improve the energy efficiency of your property. Sash windows that are in disrepair can let in drafts and allow heat to escape, leading to higher energy bills. Restoring sash windows can help to reduce these issues by improving insulation, reducing air leakage, and enhancing overall energy efficiency.



Sash windows are a traditional feature of many older properties and restoring them can help to preserve the character and heritage of the building. Restoring sash windows involves repairing or replacing damaged or missing parts while maintaining the original design and aesthetic of the windows.

Increased property value

Increased property value?

Restoration can sometimes increase the value of a property. Sash windows are a desirable feature for many homeowners, and well-maintained and restored windows can be an attractive selling point for potential buyers. Additionally, restored sash windows can enhance the overall kerb appeal of a property, making it more appealing to buyers and potentially increasing its market value.

Sash windows in conservation areas

A conservation area is a designated area of special architectural or historic interest that is protected by law to preserve its character and appearance. Conservation areas can include individual buildings, groups of buildings, streets, squares, or even entire towns or villages.

The main purpose of conservation areas is to preserve the special character and appearance of the area and to prevent inappropriate development or alterations that could harm its heritage value. In a conservation area, local planning authorities have extra controls over changes to buildings. This may include limitations on installing double glazing in your sash windows.

If this restriction applies in your area, don’t worry because SashWise have expertise in restoring sash windows in conservation areas, especially by completely refurbishing sash windows, retaining single glazed panes.  You can take advantage of draft-proofing, increased thermal efficiency all whilst preserving the character of your home and staying on the right side of the local authority.

If we install new double glazed sashes that replicate the original double glazing into existing sash boxes, this is classed as “refurbishment”, and is therefore less likely to be subject to planning permission or building regulation approval.

If you want or need completely new sash windows including the boxes then these may require planning permission if your property is in a conservation area or is classed as being of ‘Townscape Merit’.  We would always advise you to contact your local council Planning Department to seek their advice.

Conservation areas

Richmond upon Thames has 85 conservation areas.

Kingston upon Thame: 26 conservation areas including areas around Grove Lane, Canbury Gardens, Coombe Hill, Old Malden.

London Borough of Ealing has 14 conservation areas including locations around Ealing Town Centre, Montpelier Park, Ealing Common.

Merton Council has designated 28 conservation areas including locations around Wimbledon Village, South Park Gardens and Wimbledon Hill Road.

More information from the blog

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