Gravesend · Kent
Bay window subsidence repairs in Gravesend
Many bays in Gravesend were butted against the house rather than bonded into it with ties or toothed brickwork. That makes the junction the first place any differential movement shows, even when the bay foundation is reasonably sound.
Guide price from£670per bay inc VAT
- Postcodes
- DA11, DA12
- Population
- about 54,000
- Area
- Kent
- Pricing region
- South East
What should you know about the ground under Gravesend?
Postcode districts DA11, DA12 cover Gravesend, a Kent town of about 54,000 people. Neighbouring towns we cover: Swanscombe (3 miles), Longfield (4 miles) and Strood (6 miles).
Shrinkable clay is widespread in Kent. Parts of Kent lie on a former coalfield, so a coal mining search is worth checking if movement has no obvious cause. Typical buildings in Kent: Victorian terraces in the Medway towns, weatherboarded and Wealden houses, 1930s semis and seaside bungalows.
Symptoms that point to bay window subsidence repairs
- Gaps opening around the internal bay window board
- Cracks above the bay window head or below the sill
- A step or slope in the bay floor towards the window
Guide prices for bay window subsidence repairs in Gravesend
Guide prices below are for homes in Gravesend, on South East rates and including VAT. A survey or good photos let us turn them into a fixed written price.
| Item | Guide price | Per |
|---|---|---|
| Bay junction crack repair and tie-inest. | £670 – £2,000 | per bay |
| Traditional underpinning of a bay | £3,350 – £7,850 | per bay |
| Mini-piled bay underpinning | £5,600 – £13,400 | per bay |
Methods for bay window subsidence repairs
Junction crack repair and tie-in
Where movement has stopped, the open joint between bay and house is raked out, stainless ties or helical bars are fixed across it, and the joint is repointed to match. Internal plaster along the crack is cut back and renewed before redecoration.
Best for: Old, stable cracks where the bay is no longer moving
Mini-piled bay underpinning
Small piles are installed to depth around or beneath the bay and linked by a reinforced beam or needles that pick up its weight. It suits deeper soft ground and heavy root activity, and the compact rigs fit into a front garden.
Best for: Deep clay, nearby trees, or poor ground below the bay
From first photo to finished repair
Photos and first view
Send photos of the outside junction, the inside corners and the window, with a scale. We give a free initial assessment and tell you whether the crack looks old and stable or whether an engineer should inspect first.
Carry out the work
Ties are fitted across the junction, or the bay is underpinned in sequence with building control inspecting the dig. The bay window and flashings are checked and eased or resealed where the movement has disturbed them.
Make good inside
Plaster around the bay and along the junction is renewed, the window board is refixed and the room is ready for decoration. Building control paperwork, where it applies, is passed to you for your records.
Rules for bay window subsidence repairs in England
In England, underpinning and other work that alters or strengthens a wall or foundation is building work under the Building Regulations (Part A, structure), so building control approves and inspects it. Like-for-like repairs often are not, and we tell you which applies before a price is agreed. Work to a party wall, or excavation close to a neighbour’s foundations, can also need a notice under the Party Wall etc. Act 1996.
Frequently asked questions
How much should I budget for bay window subsidence repairs in Gravesend?
Guide prices for bay window subsidence repairs in Gravesend start from about £670 per bay, including VAT, on South East rates. Your fixed written price follows photos or a survey and depends on the extent of the work and access.
Can you survey a property in Gravesend?
We do. Gravesend and the surrounding area are covered, including nearby Swanscombe and Longfield. A free initial assessment from your photos is the first step.
Why do houses in Kent crack?
North Kent sits on London Clay, central Kent on Gault and Weald Clays and the Downs on chalk, so shrinkable clay is widespread. East Kent around Deal and Dover had a small deep coalfield, worked until the late 1980s. Only an investigation can say why a particular building has moved.
Does a bay window always need underpinning?
No, many bays are fixed by tying the junction and repointing, once any cause such as a leaking gully is put right. Underpinning is for bays still dropping after the cause has been dealt with, or with footings too shallow for the ground they sit on.
Can I just fill the crack myself?
Filling it hides the evidence without dealing with the cause, and if the bay is still moving the crack will reopen. Photograph it with a scale and date first. If you plan to claim on insurance, tell your insurer before any repair, including filling.
Related work in Gravesend
- Floor joist repairs
- Underpinning
- Structural crack repairs
- Crack stitching
- Boundary and garden wall repairs
Bay window subsidence repairs near Gravesend
Photos of the bay floor, window and junction crack are enough to start; send them about your Gravesend home and we will reply with a view.