Burnley · Lancashire
Bay window subsidence repairs in Burnley
Many bays in Burnley 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£575per bay inc VAT

- Postcodes
- BB10, BB11
- Population
- about 150,000
- Area
- Lancashire
- Pricing region
- North West
Is Lancashire prone to ground movement?
Burnley (BB10, BB11) has around 150,000 residents and sits in Lancashire. Nearby places we cover include Nelson (3 miles), Colne (5 miles) and Accrington (6 miles).
Clay soils are found in parts of Lancashire. Parts of Lancashire lie on a former coalfield, so a coal mining search is worth checking if movement has no obvious cause. What you mostly find across Lancashire: stone and brick mill terraces, seaside villas in Blackpool and Lytham, and inter-war and post-war semis.
What to look for before calling about bay window subsidence repairs
- Bay roof or lead flashing pulling away from the main wall
- A step or slope in the bay floor towards the window
- Cracks above the bay window head or below the sill
Bay window subsidence repairs prices in Burnley
Guide prices below are for homes in Burnley, on North West 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. | £575 – £1,750 | per bay |
| Traditional underpinning of a bay | £2,900 – £6,700 | per bay |
| Mini-piled bay underpinning | £4,800 – £11,500 | per bay |
How we usually approach 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
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.
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.
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 Burnley
How much should I budget for bay window subsidence repairs in Burnley?
Guide prices for bay window subsidence repairs in Burnley start from about £575 per bay, including VAT, on North West 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 Burnley?
Yes. We take enquiries from across Burnley, including BB10, BB11, and from nearby places such as Nelson and Colne. Send photos for a free initial view and we will tell you what happens next.
Why do houses in Lancashire crack?
Lancashire is mostly glacial till over sandstone and mudstone, with the Burnley and Accrington coalfield in the east and soft coastal and estuarine ground on the Fylde. Old mill and mine sites leave made ground in many towns. 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.
Can a bay be underpinned without underpinning the house?
Yes, underpinning only the bay is common because it is usually the part on shallower footings. The engineer designs the junction so the strengthened bay and the existing house can move slightly without cracking, sometimes with a movement joint or ties.
Related work in Burnley
- Concrete repairs
- Extension pulling away repairs
- Gable end wall repairs
- Floor joist repairs
- Lintel replacement
Bay window subsidence repairs near Burnley
For a no-obligation written quote on bay window subsidence in Burnley, call or send a few photos with a tape measure in shot.