Poole · Dorset
Floor joist repairs in Poole
Houses in Poole and across Dorset 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£260per joist inc VAT
- Postcodes
- BH14, BH15, BH17
- Population
- about 150,000
- Area
- Dorset
- Pricing region
- South West
Why does the ground in Dorset matter for floor joist repairs?
Postcode districts BH14, BH15, BH17 cover Poole, a Dorset town of about 150,000 people. If you are just outside Poole, we also cover Bournemouth (5 miles), Wimborne Minster (5 miles) and Ferndown (7 miles).
Dorset has a mix of ground, with clay in some places and firmer rock in others. Ground movement here is more often linked to soils, drains and trees than to mining. What you mostly find across Dorset: stone and brick villages, Victorian villas in Bournemouth, and inter-war and post-war semis.
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
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
- Floor dipping towards an outside wall or in the middle of the room
- A musty smell, or fungal strands showing between the boards
- Floor bouncing, or ornaments rattling, when someone walks across
Floor joist repairs prices in Poole
The ranges below reflect typical South West costs for floor joist repairs, including VAT. Scaffold, access and making good can push a job to the top of the range.
| Item | Guide price | Per |
|---|---|---|
| Splicing or sistering a damaged joist | £260 – £410 | per joist |
| Whole room of joists and boards | £2,050 – £6,200 | per room |
| Sleeper wall rebuild and ventilationest. | £410 – £1,550 | per room |
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 Poole
How much will floor joist repairs cost in Poole?
Guide prices for floor joist repairs in Poole start from about £260 per joist, including VAT, on South West rates. Your fixed written price follows photos or a survey and depends on the extent of the work and access.
Do you cover Poole?
Yes. We take enquiries from across Poole, including BH14, BH15, BH17, and from nearby places such as Bournemouth and Wimborne Minster. Send photos for a free initial view and we will tell you what happens next.
Is the ground in Dorset prone to subsidence?
Dorset mixes chalk downs, Oxford and Kimmeridge Clays in the vales, and the sands and gravels of the Poole basin. Clay vales can shrink and swell, and parts of the coast are known for landslip. 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.
What is sistering a floor joist?
Sistering is fixing a new length of timber alongside an existing joist so the two share the load. It strengthens a notched, cracked or sagging joist without removing it, so it is quicker and less disruptive than replacement.
Other structural repairs in Poole
- Chimney stack repairs
- Subsidence repairs
- Bay window subsidence repairs
- Roof structure repairs
- Lintel replacement
Floor joist repairs near Poole
Send photos of the floor and the outside wall at your Poole property for a free initial assessment and a no-obligation written quote.