Hillingdon · Greater London
Floor joist repairs in Hillingdon
Floor joist repairs in Hillingdon start underneath the boards, not on top of them. We look at the joist ends, the sleeper walls and the ventilated void before suggesting sistering, splicing or replacement, so the price reflects the timber you actually have.
Guide price from£310per joist inc VAT

- Postcodes
- HA4, UB3, UB4, UB7, UB8
- Population
- about 300,000
- Area
- Greater London
- Pricing region
- London
What should you know about the ground under Hillingdon?
Hillingdon takes in postcode districts including HA4, UB3, UB4, UB7, UB8, with about 300,000 residents. If you are just outside Hillingdon, we also cover Ealing (5 miles), Gerrards Cross (6 miles) and Hounslow (6 miles).
Much of Greater London 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. Across Greater London, most homes are Victorian and Edwardian terraces with shallow footings, inter-war semis in the outer boroughs, and converted flats and mansion blocks.
Floor joist repairs prices in Hillingdon
Guide prices below are for homes in Hillingdon, on London 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 | £310 – £500 | per joist |
| Whole room of joists and boards | £2,500 – £7,500 | per room |
| Sleeper wall rebuild and ventilationest. | £500 – £1,900 | 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
Splicing ends and fitting hangers
Where only the end has rotted, it is cut back to sound timber and a new piece is fixed alongside, bearing on the wall or on a new joist hanger. Missing or under-nailed hangers elsewhere are replaced at the same time. The damp in the wall must be fixed too.
Best for: Rotten joist ends in damp solid walls
What happens during floor joist repairs, step by step?
Lift boards and inspect
On site we lift a few boards where the floor is worst and check the joist ends, sleeper walls and void with a moisture meter. Outside, we look for high ground, blocked vents and leaks keeping the timber wet.
Written quote
You get a no-obligation written quote listing which joists are sistered, spliced or replaced and any sleeper wall or ventilation work. It becomes a fixed price in writing once the repair is specified.
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
- Floor bouncing, or ornaments rattling, when someone walks across
- Ceiling cracks below that follow the line of the joists
- Soft or spongy boards near outside walls, hearths or the bathroom
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 Hillingdon
What is the price of floor joist repairs in Hillingdon?
Guide prices for floor joist repairs in Hillingdon start from about £310 per joist, including VAT, on London rates. Your fixed written price follows photos or a survey and depends on the extent of the work and access.
Do you carry out floor joist repairs in Hillingdon?
Yes, Hillingdon is covered, along with postcode districts HA4, UB3, UB4, UB7. We also cover nearby Ealing and Gerrards Cross.
Does the ground around Hillingdon cause cracking?
Most of Greater London sits on London Clay, among the most shrinkage-prone ground in the UK, with river gravels along the Thames. Subsidence claims here are among the most frequent in the country, especially after dry summers and near street and garden trees. Only an investigation can say why a particular building has moved.
Why is my floor bouncy?
A bouncy floor usually means the joists are deflecting too much, often because they span too far, have lost their strutting or have been weakened by notches. It rarely means imminent failure, but it is worth checking, especially if the bounce appeared after work in the room.
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.
More repairs we carry out in Hillingdon
Floor joist repairs near Hillingdon
Get a free initial assessment of a sagging floor in Hillingdon from your photos or a call, before you commit to anything.