Farnham · Surrey
Bay window subsidence repairs in Farnham
If your Farnham 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£670per bay inc VAT
- Postcodes
- GU9, GU10
- Population
- about 37,000
- Area
- Surrey
- Pricing region
- South East
Is Surrey prone to ground movement?
Farnham (GU9, GU10) has around 37,000 residents and sits in Surrey. Nearby places we cover include Aldershot (3 miles), Fleet (5 miles) and Farnborough (6 miles).
Shrinkable clay is widespread in Surrey. Ground movement here is more often linked to soils, drains and trees than to mining. What you mostly find across Surrey: Victorian and Edwardian villas, 1930s semis and detached houses in the commuter towns, and post-war estates.
Bay window subsidence repairs prices in Farnham
Guide prices below are for homes in Farnham, 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 |
How we usually approach 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
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
What happens during bay window subsidence repairs, step by step?
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.
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.
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.
What to look for before calling about bay window subsidence repairs
- Gaps opening around the internal bay window board
- Bay window sash or casement sticking or binding
- A step or slope in the bay floor towards the window
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 Farnham
How much will bay window subsidence repairs cost in Farnham?
Guide prices for bay window subsidence repairs in Farnham 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.
Do you cover Farnham?
Yes, Farnham is covered, along with postcode districts GU9, GU10. We also cover nearby Aldershot and Fleet.
Is the ground in Surrey prone to subsidence?
North Surrey sits on London Clay, the south on Weald Clay, with chalk along the North Downs and sands in the west. Large gardens with mature trees on clay make seasonal subsidence a familiar problem. 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.
Is a crack between my bay and the house serious?
It is often not serious, especially if it is old, fine and unchanged for years. A crack that is widening, tapering or matched by sticking windows and a sloping bay floor needs looking at. An engineer’s inspection, sometimes with monitoring, will confirm whether the bay is still moving.
Other structural repairs in Farnham
- Structural surveys and crack monitoring
- Lintel replacement
- Extension pulling away repairs
- Floor joist repairs
- Underpinning
Bay window subsidence repairs near Farnham
Not sure whether your Farnham bay is still moving? Send dated photos, and we will suggest whether monitoring or a repair comes next.