How Much Does It Cost to Restore Sash Windows?

The cost to restore sash windows usually depends on the condition of the timber, the amount of repair work required, whether the glass needs replacing, and whether draught proofing is included. For period homes, listed buildings, and properties of English Heritage interest, restoration is often preferred because it helps preserve the original character and historic value of the windows.

As a general guide, a full sash window restoration can cost around £650 per window for a standard restoration. This would typically include stripping the window back, freeing stuck sashes, replacing broken sash cords, balancing the weights, repairing timber where needed, and making sure the window opens and closes smoothly again.

Around 10 years ago, many sash window restorers were charging approximately £450 per window for a full restoration. With the rising cost of materials, labour, fuel, glass, putty, resin, timber, and general business costs, a similar job today is often closer to £650 per window, depending on the condition of the window.

Draught proofing is usually an additional cost. For many sash windows, professional draught proofing may add around £250 per window, depending on the type of system used and the amount of preparation required.

Current UK cost guides place sash window restoration commonly in the region of £620–£920 per window, with draught proofing often priced separately at around £250–£400 per window.

What Is Included in Sash Window Restoration?

A proper sash window restoration is more than a quick repair. The aim is to return the original window to good working order while keeping as much of the existing timber and character as possible.

A typical sash window restoration may include:

Removing the sashes from the frame

Checking the condition of the box frame, sills, rails and stiles

Replacing broken or worn sash cords

Rebalancing the weights

Freeing painted-shut or jammed windows

Repairing rotten timber

Using resin repairs where suitable

Replacing cracked or broken single glazing

Re-puttying loose or failed glass

Adjusting the sashes so they slide properly

Making the window open and close smoothly

Preparing the window for painting or finishing

When done properly, a restored sash window should be easy to use. A well-balanced sash window should move smoothly and stay open without dropping. In many cases, you should be able to open it with one finger.

Average Cost to Restore Sash Windows

For a standard timber sash window, the average cost to restore sash windows may be around:

Basic sash window repair: £250–£400 per window
Full sash window restoration: £600–£900 per window
Restoration with draught proofing: £850–£1,150 per window
Heavy timber repair or rotten sill replacement: Additional cost depending on damage
Single glazed pane replacement: Additional cost depending on glass size and type

These prices can vary depending on the size of the window, access, the level of rot, the condition of the paintwork, and whether the property is listed or in a conservation area.

Other UK pricing guides show full refurbishment ranging from around £650 to £1,200+ per window, especially where timber repairs, redecoration, rebalancing and more detailed restoration are involved.

Why Does Sash Window Restoration Cost More Today?

If you had sash windows restored 10 years ago, the price may have been much lower. A job that once cost around £450 per window may now be closer to £650 per window for the same level of work.

There are several reasons for this:

Labour costs have increased

Timber and resin repair materials cost more

Glass and putty prices have risen

Insurance, transport and workshop costs are higher

Restoration work is skilled and time-consuming

Older windows are often in worse condition than they first appear

Sash window restoration is a specialist trade. It takes time to remove the sashes, repair them correctly, balance the weights, replace cords, reglaze where needed, and make the window work properly again.

Is Draught Proofing Included in the Restoration Cost?

Draught proofing is often priced separately from standard sash window restoration.

A full restoration may make the window work properly again, but draught proofing helps reduce cold air, rattles, dust and outside noise. This is usually done by fitting discreet brush seals into the staff beads, parting beads and meeting rails.

As a guide, sash window draught proofing can cost around £250 per window, although some companies may charge more depending on the window size and condition. Many current UK guides place professional sash window draught proofing between £200 and £400 per window.

Draught proofing is worth considering if you want the restored sash windows to feel warmer, quieter and more comfortable.

Restore or Replace Sash Windows?

In many period properties, restoring sash windows is better than replacing them.

Original timber sash windows were often made from high-quality slow-grown timber. Even if they look tired, they can often be repaired, re-corded, rebalanced, draught proofed and repainted.

Replacement sash windows can cost significantly more, especially if they are made from timber. Some current guides place new timber sash window replacement at around £1,500+ per window, with bespoke or London pricing often higher.

Restoration is usually the better choice when:

The original timber is mostly sound

The property is listed

The home is in a conservation area

You want to keep the period character

The windows only need cords, glass, resin repairs or draught proofing

You want to avoid the higher cost of full replacement

Replacement may only be needed when the timber is beyond repair or the existing windows have already been badly altered.

Cost Example

For one standard sash window, you might expect something like:

Full sash window restoration: around £650

Draught proofing: around £250

Estimated total: around £900 per window

This would cover a typical restoration where the window needs new cords, balancing, minor timber repairs, reglazing where needed, re-puttying, easing, adjustment and draught proofing.

The final price may be lower if the window is in good condition, or higher if there is heavy rot, broken glass, sill damage, difficult access or listed building requirements.

What Affects the Cost to Restore Sash Windows?

The main factors that affect sash window restoration cost include:

Window size

Condition of the timber

Amount of rot

Whether the sill needs repair

Whether glass needs replacing

Whether the weights need adjusting

Whether the window has been painted shut

Whether draught proofing is required

Whether the property is listed

Access to upper floors

Amount of preparation needed before painting

Every sash window is different, so the most accurate way to price restoration is to inspect the window properly.

Is Sash Window Restoration Worth It?

Yes, sash window restoration is often worth it, especially in older homes, listed buildings and period properties.

Restoring sash windows can:

Keep the original character of the property

Improve how the windows open and close

Reduce draughts

Stop rattling

Repair rotten timber

Improve comfort

Cost less than full replacement

Help preserve traditional craftsmanship

A restored sash window should look right, work properly and last for many years with the correct maintenance.

Conclusion

The cost to restore sash windows is usually around £650 per window for a full restoration, with draught proofing often adding around £250 per window. This means a fully restored and draught-proofed sash window may cost around £900 per window, depending on its condition.

While prices were lower 10 years ago, today’s costs reflect the extra expense of labour, materials, glass, timber, resin repairs and skilled restoration work.

For many homeowners, sash window restoration is still much more cost-effective than replacement. It preserves the original windows, improves how they work, and helps keep the period character of the property intact.The cost to restore sash windows usually depends on the condition of the timber, the amount of repair work required, whether the glass needs replacing, and whether draught proofing is included.

Around 10 years ago, many sash window restorers were charging approximately £450 per window for a full restoration. With the rising cost of materials, labour, fuel, glass, putty, resin, timber, and general business costs, a similar job today is often closer to £650 per window, depending on the condition of the window.