By Emily Rivers
Last updated 5th May 2023

How Much Does it Cost to Replace a Window Sill in 2023?

Wooden window sills give a timeless look to a property, especially period homes. But they don't last forever – and when they become rotten, they could let rain into your home and cause damp.

It's important to get damaged window sills repaired or replaced as soon as possible – but how much does it cost to replace a window sill?

Window sill replacement and repair cost

How much it costs to replace or repair your window sill will depend on the size and type of window, the wood you choose and where you live. But here are the average costs to expect:

Job

Average cost

Window sill replacement (including labour & materials)

£140-£220

Severely rotten window sill replacement and frame (including labour & materials)

£300-£350

Sash window sill replacement (including labour & materials)

£120-£340

Bay window sill replacement (including labour & materials)

£170-£200

Door threshold repair

£60-£110

Carpenter hourly rate

£16-£40

These window sill repair and replacement prices are taken from averages across the entire UK. If you live in a major city or the south east, expect to pay more. If you live in more remote areas of the country, you may pay less for a carpenter.

HaMuch has a huge database of hourly and daily rates for carpenters all over the UK, so take a look at the table further down the page to find out how much to expect to pay for a carpenter in your area.

Window sill replacement cost

How much does it cost to replace rotten wood around a window?

If your wooden window frame is rotten as well as your window sill, this will drive up the cost of window sill replacement. Expect it to cost up to £350 to replace the rotten wood around a window and the window sill.

How do I know if my window sill is rotten?

You'll know if your window sill is rotten by the way it looks and feels. The signs of a rotten window sill are the same whether they are internal or external wooden window sills:

Look for peeling or cracked paint. If the paintwork is damaged, that usually means that water has penetrated the surface and therefore damaged the sill itself.

Check to see whether your window sill is spongy. If you press your window sill and it feels soft and springy, that means it's rotten.

Spot crumbliness or brittleness. Touch your window sill – does it crumble away under your fingers? That means it's definitely time to replace it.

How long does it take to replace a window sill?

For an average-sized window, it should only take a carpenter between 1-2 hours to replace your window sill. That's assuming that they are replacing a wooden window sill with another one – if they are replacing a window sill made from stone or concrete with a wooden one, it may take longer as it will be harder to remove the old one.

If you want to replace all the window sills in your home, expect it to take around 1-3 days. It will of course depend on the number of windows you have in your home and how big it is.

What kind of wood should you use to replace a window sill?

You'll want to use a hard-wearing wood that's been treated to give it water-resistant properties. Chestnut, mahogany, maple and oak are often used for wooden window sills.

To maximise the life of your window sills, you should maintain them regularly. Make sure you paint them with a good-quality gloss, satin or eggshell paint that is designed for wood. Brands like Dulux, Armstead or Johnstone's are good options and cost between £11-£25 per litre. If you want a decorator to paint your window sills for you, expect this to cost around £200 for around 4 window sills and frames in your home.

You could also stain your window sills to give them more water resistance. Ronseal, Dulux, Sadolin and Osmo are all good brands of woodstain for internal and external wooden window sills. Expect to pay between £10-£15 for a 250ml tin of woodstain.

Can you put new wood over rotten wood?

We wouldn't recommend putting new wood over rotten wood. If you try to put a new wooden window sill over a rotten one, it's likely that your new window sill will just end up rotting more quickly.

If your wood window sill isn't rotten in all places, you may be able to remove the rotten parts and fill them with a soft wood polyester filler. It will help keep your window sill strong for a few more years, but you will ultimately need to replace your window sill.

Is it easy to install your own window sill?

It's not that easy to install your own window sill. That's why we'd always recommend getting a carpenter to replace your window sill for you.

Getting a good finish on a wooden window sill involves cutting it to perfect size and fixing nails and screws in a way that keeps them hidden. You also need to ensure that your window sill is fitted properly to ensure that rainwater doesn't get into your home.

To avoid causing damp problems in your property, we'd suggest getting a carpenter to fit new window sills for you. You can be sure that they're installed correctly this way, and it could even save you money if your DIY project goes wrong and you waste expensive materials.

If you're ready to get new wooden window sills, post your job on HaMuch. We'll put you in touch with local trusted carpenters that are ready to do the work.


Estimates for common carpenter & joiner jobs;

Rates for other trades

Window sill replacement cost in the UK
Window sill replacement cost in the UK (excluding VAT or callout charges)
Location in UKWindow sill replacement cost
Window sill replacement near Aberdeen£434
Window sill replacement near Amber Valley£392
Window sill replacement near Angus£438
Window sill replacement near Arun£442
Window sill replacement near Ashfield£382
Window sill replacement near Aylesbury Vale£444
Window sill replacement near Barnsley£372
Window sill replacement near Basildon£444
Window sill replacement near Basingstoke & Deane£410
Window sill replacement near Bassetlaw£372
Window sill replacement near Bath & North East Somerset£400
Window sill replacement near Bedford£460
Window sill replacement near Belfast£270
Window sill replacement near Birmingham£358
Window sill replacement near Blackburn£356
Window sill replacement near Blackpool£332
Window sill replacement near Bolton£382
Window sill replacement near Bournemouth£408
Window sill replacement near Bracknell Forest£442
Window sill replacement near Bradford£352
Window sill replacement near Braintree£428
Window sill replacement near Breckland£378
Window sill replacement near Bridgend£358
Window sill replacement near Brighton£434
Window sill replacement near Bristol£398
Window sill replacement near Broadland£350
Window sill replacement near Broxtowe£384
Window sill replacement near Bury£384
Window sill replacement near Caerphilly£390
Window sill replacement near Calderdale£346
Window sill replacement near Cambridge£416
Window sill replacement near Canterbury£380
Window sill replacement near Cardiff£394
Window sill replacement near Carmarthenshire£322
Window sill replacement near Charnwood£378
Window sill replacement near Chelmsford£436
Window sill replacement near Cheltenham£450
Window sill replacement near Cherwell£458
Window sill replacement near Chester£360
Window sill replacement near Colchester£414
Window sill replacement near Conway£340
Window sill replacement near Coventry£352
Window sill replacement near Crewe & Nantwich£424
Window sill replacement near Dacorum£444
Window sill replacement near Derby£392
Window sill replacement near Doncaster£358
Window sill replacement near Dover£372
Window sill replacement near Dudley£354
Window sill replacement near Dumfries & Galloway£314
Window sill replacement near Dundee£462
Window sill replacement near East Ayrshire£382
Window sill replacement near East Devon£362
Window sill replacement near East Dunbartonshire£356
Window sill replacement near East Hampshire£416
Window sill replacement near East Hertfordshire£458
Window sill replacement near East Riding£374
Window sill replacement near Eastleigh£418
Window sill replacement near Edinburgh£426
Window sill replacement near Elmbridge£456
Window sill replacement near Epping Forest£454
Window sill replacement near Erewash£384
Window sill replacement near Exeter£348
Window sill replacement near Falkirk£382
Window sill replacement near Fife£470
Window sill replacement near Flintshire£368
Window sill replacement near Gateshead£340
Window sill replacement near Gedling£372
Window sill replacement near Glasgow£352
Window sill replacement near Gloucester£428
Window sill replacement near Guildford£440
Window sill replacement near Gwynedd£318
Window sill replacement near Halton£358
Window sill replacement near Harrogate£354
Window sill replacement near Havant & Waterloo£410
Window sill replacement near Highland£404
Window sill replacement near Horsham£428
Window sill replacement near Huntingdonshire£456
Window sill replacement near Ipswich£416
Window sill replacement near Isle of Wight£398
Window sill replacement near Kings Lynn & West Norfolk£380
Window sill replacement near Kingston-upon-Hull£342
Window sill replacement near Kirklees£368
Window sill replacement near Knowsley£352
Window sill replacement near Lancaster£366
Window sill replacement near Leeds£360
Window sill replacement near Leicester£370
Window sill replacement near Lisburn£270
Window sill replacement near Liverpool£348
Window sill replacement near London£452
Window sill replacement near Luton£450
Window sill replacement near Macclesfield£408
Window sill replacement near Maidstone£416
Window sill replacement near Manchester£394
Window sill replacement near Mid Bedfordshire£452
Window sill replacement near Mid Sussex£420
Window sill replacement near Middlesbrough£408
Window sill replacement near Milton Keynes£438
Window sill replacement near Neath Port Talbot£360
Window sill replacement near New Forest£416
Window sill replacement near Newbury£406
Window sill replacement near Newcastle-under-Lyme£412
Window sill replacement near Newcastle-upon-Tyne£338
Window sill replacement near Newport£396
Window sill replacement near North Ayrshire£372
Window sill replacement near North East Lincolnshire£372
Window sill replacement near North Hertfordshire£460
Window sill replacement near North Lanarkshire£358
Window sill replacement near North Lincolnshire£350
Window sill replacement near North Somerset£402
Window sill replacement near North Tyneside£338
Window sill replacement near North Wiltshire£404
Window sill replacement near Northampton£440
Window sill replacement near Norwich£360
Window sill replacement near Nottingham£384
Window sill replacement near Nuneaton & Bedworth£358
Window sill replacement near Oldham£388
Window sill replacement near Oxford£454
Window sill replacement near Pembrokeshire£400
Window sill replacement near Perth & Kinross£528
Window sill replacement near Peterborough£474
Window sill replacement near Plymouth£354
Window sill replacement near Poole£410
Window sill replacement near Portsmouth£412
Window sill replacement near Preston£336
Window sill replacement near Reading£436
Window sill replacement near Redcar & Cleveland£404
Window sill replacement near Reigate & Banstead£450
Window sill replacement near Renfrewshire£374
Window sill replacement near Rhondda, Cynon, Taff£382
Window sill replacement near Rochdale£378
Window sill replacement near Rochester-upon-Medway£460
Window sill replacement near Rotherham£368
Window sill replacement near Salford£392
Window sill replacement near Salisbury£424
Window sill replacement near Sandwell£354
Window sill replacement near Scarborough£436
Window sill replacement near Scottish Borders£446
Window sill replacement near Sefton£346
Window sill replacement near Sevenoaks£436
Window sill replacement near Sheffield£364
Window sill replacement near Slough£452
Window sill replacement near Solihull£350
Window sill replacement near South Ayrshire£384
Window sill replacement near South Bedfordshire£460
Window sill replacement near South Cambridgeshire£440
Window sill replacement near South Gloucestershire£394
Window sill replacement near South Kesteven£400
Window sill replacement near South Lanarkshire£322
Window sill replacement near South Oxfordshire£444
Window sill replacement near South Somerset£490
Window sill replacement near South Tyneside£340
Window sill replacement near Southampton£418
Window sill replacement near Southend-on-Sea£424
Window sill replacement near St Albans£448
Window sill replacement near St Helens£356
Window sill replacement near Stafford£400
Window sill replacement near Stockport£398
Window sill replacement near Stockton-on-Tees£408
Window sill replacement near Stoke-on-Trent£406
Window sill replacement near Stratford-on-Avon£370
Window sill replacement near Stroud£420
Window sill replacement near Suffolk Coastal£410
Window sill replacement near Sunderland£344
Window sill replacement near Swale£406
Window sill replacement near Swansea£350
Window sill replacement near Tameside£392
Window sill replacement near Teignbridge£366
Window sill replacement near Tendring£414
Window sill replacement near Test Valley£412
Window sill replacement near Thamesdown£392
Window sill replacement near Thanet£374
Window sill replacement near The Wrekin£356
Window sill replacement near Thurrock£440
Window sill replacement near Torbay£360
Window sill replacement near Trafford£394
Window sill replacement near Vale of Glamorgan£402
Window sill replacement near Vale of White Horse£440
Window sill replacement near Vale Royal£368
Window sill replacement near Wakefield£356
Window sill replacement near Walsall£358
Window sill replacement near Warrington£378
Window sill replacement near Warwick£348
Window sill replacement near Waveney£348
Window sill replacement near Waverley£434
Window sill replacement near Wealden£422
Window sill replacement near West Lancashire£344
Window sill replacement near West Lothian£412
Window sill replacement near West Wiltshire£404
Window sill replacement near Wigan£368
Window sill replacement near Windsor & Maidenhead£450
Window sill replacement near Wirral£350
Window sill replacement near Wokingham£442
Window sill replacement near Wolverhampton£366
Window sill replacement near Wrexham Maelor£386
Window sill replacement near Wychavon£388
Window sill replacement near Wycombe£468
Window sill replacement near York£372