Horsham · West Sussex
Floor joist repairs in Horsham
Houses in Horsham and across West Sussex with suspended timber ground floors rely on dry walls and a ventilated void to stay sound. When either fails, rot usually starts at the edges of the room long before anything shows in the middle.
Guide price from£280per joist inc VAT
- Postcodes
- RH12
- Population
- about 51,000
- Area
- West Sussex
- Pricing region
- South East
What is the ground like in West Sussex?
We cover Horsham and its postcode districts RH12, part of West Sussex, with a population of roughly 51,000. If you are just outside Horsham, we also cover Crawley (7 miles), Horley (11 miles) and Haywards Heath (11 miles).
Shrinkable clay is widespread in West Sussex. Ground movement here is more often linked to soils, drains and trees than to mining. Across West Sussex, most homes are Wealden cottages, 1930s semis and bungalows on the coast, and new-town estates in Crawley.
What happens during floor joist repairs, step by step?
Photos and a call
Send photos of the dip or soft area, the outside wall at ground level and any air bricks. A short call about when it started, and any recent plumbing or heating work, tells us whether the problem is local or widespread.
Repair the structure
Boards are lifted and numbered if they are going back, and rotten timber is cut out. New treated timber is fixed and checked with a level before strutting, hangers and any restraint straps go in.
Relay and ventilate
Boards are relaid or replaced, skirting refitted and air bricks cleared or added outside. We point out anything that would let damp back in, such as soil heaped against the wall, so the repair lasts.
What to look for before calling about floor joist repairs
- Soft or spongy boards near outside walls, hearths or the bathroom
- Floor bouncing, or ornaments rattling, when someone walks across
- Ceiling cracks below that follow the line of the joists
Floor joist repairs prices in Horsham
Guide prices below are for homes in Horsham, 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 |
|---|---|---|
| Splicing or sistering a damaged joist | £280 – £450 | per joist |
| Whole room of joists and boards | £2,250 – £6,700 | per room |
| Sleeper wall rebuild and ventilationest. | £450 – £1,700 | per room |
How we usually approach floor joist repairs
Replacing joists and boards
When rot or woodworm runs through most of a floor, it is usually cheaper to replace the joists, strutting and boards together. Where joists run parallel to an outside wall, restraint straps tie the new floor back to it so the wall keeps its lateral support.
Best for: Widespread rot, or a whole floor that has dropped
Sistering a joist
A new length of treated timber, the same depth as the original, is bolted or screwed alongside the damaged joist so the two share the load. It is the quickest fix for a notched, cracked or sagging joist that is otherwise sound, usually after lifting a few boards.
Best for: Cut, cracked or sagging joists with sound ends
Rules for floor joist repairs in England
Like-for-like repairs such as crack stitching and repointing do not usually need building control approval in England, but anything that changes or strengthens the structure, such as underpinning or rebuilding a wall, does. If the work touches a party wall, the Party Wall etc. Act 1996 may apply.
Questions about floor joist repairs in Horsham
How much will floor joist repairs cost in Horsham?
Guide prices for floor joist repairs in Horsham start from about £280 per joist, 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 Horsham?
We do. Horsham and the surrounding area are covered, including nearby Crawley and Horley. A free initial assessment from your photos is the first step.
Is the ground in West Sussex prone to subsidence?
North West Sussex around Crawley and Horsham sits on Weald Clay, the South Downs are chalk, and the coastal plain has brickearth and gravels. The Weald Clay is prone to shrink-swell movement near trees. Only an investigation can say why a particular building has moved.
Do I need building control for floor joist repairs?
Usually not for like-for-like repairs to a few joists, but replacing a whole floor structure can be building work. In Scotland that generally needs a building warrant, and in Northern Ireland council building control applies. We deal with building control where the work needs it.
Can floor joists be repaired without taking up the whole floor?
Yes, in most cases only the boards over the affected joists need lifting, and three or four boards are often enough to sister a joist or splice a rotten end. Widespread rot is the exception, because the whole floor must come up to remove the decay.
Other structural repairs in Horsham
- Structural surveys and crack monitoring
- Underpinning
- Roof structure repairs
- Boundary and garden wall repairs
- Bowing wall repairs
Floor joist repairs near Horsham
Each joist, sleeper wall and air brick at your Horsham property is itemised in the written quote, then fixed in price once the repair is specified.