Eastleigh · Hampshire
Bay window subsidence repairs in Eastleigh
Many bays in Eastleigh 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
- SO50, SO53
- Population
- about 54,000
- Area
- Hampshire
- Pricing region
- South East
Is Hampshire prone to ground movement?
Eastleigh is in Hampshire and takes in postcode districts SO50, SO53. About 54,000 people live there. If you are just outside Eastleigh, we also cover Hedge End (4 miles), Southampton (5 miles) and Romsey (7 miles).
Much of Hampshire sits on clay that shrinks in dry summers and swells in wet winters. Ground movement here is more often linked to soils, drains and trees than to mining. Housing stock in Hampshire: Victorian terraces in Portsmouth and Southampton, 1930s semis, and large post-war and new-build estates.
How we usually approach bay window subsidence repairs
Traditional underpinning of the bay
The bay footing is excavated in short sections and new mass concrete is placed down to firmer ground below the zone affected by roots and seasons. Because a bay is a short length of wall, the work is compact, but it needs building control approval.
Best for: Active bay movement on firm ground at moderate depth
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
What happens during bay window subsidence repairs, step by step?
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.
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.
What to look for before calling about bay window subsidence repairs
- A vertical crack where the bay meets the front wall
- Bay roof or lead flashing pulling away from the main wall
- Bay window sash or casement sticking or binding
Bay window subsidence repairs prices in Eastleigh
Guide prices below are for homes in Eastleigh, 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 |
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.
Questions about bay window subsidence repairs in Eastleigh
How much should I budget for bay window subsidence repairs in Eastleigh?
Guide prices for bay window subsidence repairs in Eastleigh 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 Eastleigh?
We do. Eastleigh and the surrounding area are covered, including nearby Hedge End and Southampton. A free initial assessment from your photos is the first step.
Why do houses in Hampshire crack?
Central Hampshire is chalk, while the south around Portsmouth, Southampton and the New Forest fringe and the north-east around Farnborough sit on London Clay, Reading Beds and other clays and sands. The clay areas see seasonal movement near trees. Only an investigation can say why a particular building has moved.
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.
Will the bay window need replacing?
Usually not. Most windows can be eased, packed or resealed once the bay is stable. If the frame has twisted badly or the glass has cracked, replacement may be worth considering. Under a claim, upgrades beyond like-for-like are normally priced separately.
Related work in Eastleigh
- Bowing wall repairs
- Resin injection ground stabilisation
- Wall tie replacement
- Subsidence insurance claim repairs
- Chimney stack repairs
Bay window subsidence repairs near Eastleigh
For a no-obligation written quote on bay window subsidence in Eastleigh, call or send a few photos with a tape measure in shot.