Kent · England
Roof structure repairs in Kent
We arrange surveys and price roof structure repairs throughout Kent. Shrinkable clay is widespread in Kent, and we take that into account before recommending a method.
Guide price from£335per rafter inc VAT

- Area
- Kent
- Pricing region
- South East
- Ground
- Shrinkable clay widespread
- Towns listed
- 22
What should you know about the ground under Kent?
North Kent sits on London Clay, central Kent on Gault and Weald Clays and the Downs on chalk, so shrinkable clay is widespread. East Kent around Deal and Dover had a small deep coalfield, worked until the late 1980s.
Parts of Kent lie on a former coalfield, so a coal mining search is worth checking if movement has no obvious cause. Across Kent, most homes are Victorian terraces in the Medway towns, weatherboarded and Wealden houses, 1930s semis and seaside bungalows.
From first photo to finished repair
Loft and outside survey
On site we check rafter sizes and spacing, purlins, struts, ties and wall plates, look for rot and past alterations, and measure any lean at the wall head. The covering is noted too, because its weight affects the repair.
Written quote
You receive a no-obligation written quote listing each timber repair, any ties or straps, propping, scaffolding and making good. Once the repair is specified, the figure becomes a fixed price in writing.
Prop, strengthen and tie
The roof is propped where members are being changed, then rafters, purlins, struts and ties are repaired or added as specified. Coverings disturbed by the work are relaid, and building control inspects where the work needs it.
Symptoms that point to roof structure repairs
- Ridge line dipping in the middle when seen from the street
- Struts, collars or ties cut out or missing in the loft
- Daylight through the tiles, or timber that is damp, stained or crumbling
- Horizontal cracks in the wall just below the eaves or ceiling line
Guide prices for roof structure repairs in Kent
Guide prices below are for homes in Kent, 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 |
|---|---|---|
| Repairing or doubling a rafter | £335 – £670 | per rafter |
| Purlin and strut strengthening | £1,350 – £3,350 | per roof |
| Tying in roof spread (straps and ties)est. | £895 – £2,800 | per roof |
Methods for roof structure repairs
Purlin and strut strengthening
Undersized purlins are strengthened with extra timber or replaced, and new struts are taken down to a load-bearing wall. Where there is no suitable wall, an engineer designs the load path. Temporary props hold the roof while members are changed.
Best for: Sagging slopes, slim purlins and struts removed from the loft
Wall plate replacement
Rotten or crushed wall plates are replaced in short lengths while the rafters above are propped, and bedded on the wall in mortar. The plate is then strapped down to the masonry. It is often combined with rafter foot splices along the same run.
Best for: Rot along the eaves where rafters bear on the wall
Tying in roof spread
New ties, collars or steel straps connect opposite rafters, or fix the rafter feet and wall plate firmly to the ceiling joists, so the outward thrust is resisted. Leaning wall heads are strapped back to the roof, and a badly spread roof may need partly rebuilding first.
Best for: Walls pushed out at eaves level by spreading rafters
Do you need approval for roof structure 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.
Towns in Kent we cover for roof structure repairs
- Maidstone
- Gillingham
- Tunbridge Wells
- Folkestone
- Margate
- Ashford
- Canterbury
- Sittingbourne
- Gravesend
- Dartford
- Ramsgate
- Dover
- Tonbridge
- Strood
- Whitstable
- Deal
- Sevenoaks
- Herne Bay
- Faversham
- Swanley
- Longfield
- Swanscombe
Frequently asked questions
Is the ground in Kent prone to subsidence?
North Kent sits on London Clay, central Kent on Gault and Weald Clays and the Downs on chalk, so shrinkable clay is widespread. East Kent around Deal and Dover had a small deep coalfield, worked until the late 1980s. Parts of Kent lie on a former coalfield, so a coal mining search is worth checking if movement has no obvious cause. Only an investigation on site can say why a particular building has moved.
How much will roof structure repairs cost in Kent?
On South East rates, roof structure repairs starts from about £335 per rafter, including VAT. The written price depends on the extent of the damage, access and whether an engineer or building control is needed.
Can heavy concrete tiles damage a roof?
Yes, if the frame was designed for lighter slate or tiles and was not strengthened. The extra weight makes rafters and purlins sag and can bring on roof spread. Before re-roofing in a heavier material, have the structure checked and notify building control.
What is roof spread?
Roof spread is when the feet of the rafters move outward because nothing is tying them together firmly enough. As they spread, the ridge drops and the tops of the walls are pushed out, often with a horizontal crack below the eaves. It is fixed by adding ties, collars or straps, sometimes with rebuilding.
Is a sagging roof ridge dangerous?
A slight, even dip in an old roof is often historic movement that stopped long ago. A sag that is getting worse, cracking timbers, walls pushing out at the eaves or recently removed struts should be checked soon. Avoid storing heavy items in the loft until then.