Trowbridge · Wiltshire
Bay window subsidence repairs in Trowbridge
If your Trowbridge bay window has started sticking and a gap has opened at the junction, it is worth finding out whether the bay is still moving. A stable crack needs a straightforward tie-in, whereas an active one may need a new foundation.
Guide price from£620per bay inc VAT
- Postcodes
- BA14
- Population
- about 41,000
- Area
- Wiltshire
- Pricing region
- South West
How do local ground conditions affect bay window subsidence repairs in Trowbridge?
With roughly 41,000 people, Trowbridge spans postcode districts BA14 in Wiltshire. Nearby, we also cover Westbury (4 miles), Melksham (5 miles) and Bath (8 miles).
Wiltshire has a mix of ground, with clay in some places and firmer rock in others. Ground movement here is more often linked to soils, drains and trees than to mining. Housing stock in Wiltshire: Stone cottages, railway terraces in Swindon, and large post-war and new-build estates.
From first photo to finished repair
Engineer and checks
Where the cause is unclear, an independent chartered structural engineer inspects, sometimes with a trial pit at the bay and a drain survey. We can arrange the engineer. Monitoring may be suggested if the movement could be seasonal.
Agree the repair
The engineer decides between tie-in repairs and underpinning. We confirm a fixed price in writing once the repair is specified, including scaffolding if needed, the bay window, roof flashing and internal making good.
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.
Symptoms that point to bay window subsidence repairs
- Cracks above the bay window head or below the sill
- Bay window sash or casement sticking or binding
- A step or slope in the bay floor towards the window
Guide prices for bay window subsidence repairs in Trowbridge
These are guide prices for Trowbridge, using South West rates and including VAT. Your written quote follows photos or a survey, and is fixed once the repair is specified.
| Item | Guide price | Per |
|---|---|---|
| Bay junction crack repair and tie-inest. | £620 – £1,850 | per bay |
| Traditional underpinning of a bay | £3,100 – £7,200 | per bay |
| Mini-piled bay underpinning | £5,150 – £12,400 | per bay |
Methods for bay window subsidence repairs
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
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
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 will bay window subsidence repairs cost in Trowbridge?
Guide prices for bay window subsidence repairs in Trowbridge start from about £620 per bay, including VAT, on South West rates. Your fixed written price follows photos or a survey and depends on the extent of the work and access.
Do you cover Trowbridge?
Yes, Trowbridge is covered, along with postcode districts BA14. We also cover nearby Westbury and Melksham.
Is the ground in Wiltshire prone to subsidence?
Southern Wiltshire is chalk, while the north around Swindon, Chippenham and Trowbridge sits on Oxford and Kimmeridge Clays that are prone to seasonal movement near trees. Bath stone was mined underground around Corsham. Only an investigation can say why a particular building has moved.
How long does bay underpinning take?
Traditional underpinning of a bay usually takes about a week on site, and mini-piling a little longer depending on depth. A junction tie-in without underpinning normally takes one to two days. Approvals and any monitoring beforehand add to the overall timeline.
Why do bay windows crack away from the house?
Bays often stand on shallower footings than the main walls, so they react to drying clay, roots and drain leaks that the deeper house foundations escape. Many bays were also never properly tied in, so any movement opens a clean vertical crack at the junction.
Other structural repairs in Trowbridge
- Lintel replacement
- Bowing wall repairs
- Brick arch repairs
- Wall tie replacement
- Extension pulling away repairs
Bay window subsidence repairs near Trowbridge
Photos of the bay floor, window and junction crack are enough to start; send them about your Trowbridge home and we will reply with a view.