Merton · Greater London
Floor joist repairs in Merton
Floor joist repairs in Merton 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
- CR4, SM4, SW19, SW20
- Population
- about 220,000
- Area
- Greater London
- Pricing region
- London
What should you know about the ground under Merton?
Merton takes in postcode districts including CR4, SM4, SW19, SW20, with about 220,000 residents. Nearby, we also cover Wandsworth (3 miles), Sutton (3 miles) and Kingston upon Thames (4 miles).
Greater London is one of the parts of the UK where clay soils are most likely to move with the seasons. Ground movement here is more often linked to soils, drains and trees than to mining. What you mostly find across Greater London: Victorian and Edwardian terraces with shallow footings, inter-war semis in the outer boroughs, and converted flats and mansion blocks.
From first photo to finished repair
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.
Symptoms that point to floor joist repairs
- Floor bouncing, or ornaments rattling, when someone walks across
- A musty smell, or fungal strands showing between the boards
- Ceiling cracks below that follow the line of the joists
Guide prices for floor joist repairs in Merton
These are guide prices for Merton, using London rates and including VAT. Your written quote follows photos or a survey, and is fixed once the repair is specified.
| 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 |
Methods for floor joist repairs
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
Sleeper walls and ventilation
Settled or damp sleeper walls are rebuilt on a sound base with a damp-proof course under new timber plates. Blocked air bricks are cleared, extra ones added where the void has dead spots, and soil or paving heaped against the outside wall is lowered.
Best for: Damp ground floor voids or joists on poor supports
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.
Frequently asked questions
What is the price of floor joist repairs in Merton?
Guide prices for floor joist repairs in Merton 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 Merton?
We do. Merton and the surrounding area are covered, including nearby Wandsworth and Sutton. A free initial assessment from your photos is the first step.
Does the ground around Merton 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.
Is a sagging floor dangerous?
A gentle, long-standing sag is usually not dangerous, and many older floors have moved slightly over a century. A sag that is getting worse, soft boards or a floor dropping near a wall needs checking soon, because rotten joist ends can lose their bearing.
Will my insurance pay for rotten floor joists?
Usually not, because rot, woodworm and gradual wear are standard exclusions. Damage from a sudden escape of water, or a floor that dropped through subsidence, may be treated differently. Check your policy, and tell your insurer before permanent repairs start if either applies.
More repairs we carry out in Merton
- Retaining wall repairs
- Brick arch repairs
- Roof structure repairs
- Subsidence repairs
- Bay window subsidence repairs
Floor joist repairs near Merton
For a guide price on floor joist repairs in Merton, use the quote tool or send photos of the dip, any soft boards and the air bricks.