Portishead · Somerset
Roof structure repairs in Portishead
A dipping ridge or a wavy roof slope in Portishead is usually a timber problem, not a tile problem. We look at the rafters, purlins, struts and ties from the loft, and at the wall heads from outside, before suggesting how to strengthen it.
Guide price from£310per rafter inc VAT

- Postcodes
- BS20
- Population
- about 26,000
- Area
- Somerset
- Pricing region
- South West
What should you know about the ground under Portishead?
With roughly 26,000 people, Portishead spans postcode districts BS20 in Somerset. If you are just outside Portishead, we also cover Nailsea (3 miles), Clevedon (5 miles) and Kingswood (11 miles).
Somerset has a mix of ground, with clay in some places and firmer rock in others. Parts of Somerset lie on a former coalfield, so a coal mining search is worth checking if movement has no obvious cause. Across Somerset, most homes are Bath stone Georgian terraces, Victorian houses in Taunton and Weston-super-Mare, and post-war estates.
What should you budget for roof structure repairs in Portishead?
For Portishead we use South West rates. Treat the table as a budget guide, inc VAT; the price you pay is the one on your written quote.
| Item | Guide price | Per |
|---|---|---|
| Repairing or doubling a rafter | £310 – £620 | per rafter |
| Purlin and strut strengthening | £1,250 – £3,100 | per roof |
| Tying in roof spread (straps and ties)est. | £825 – £2,600 | per roof |
Repair options we may recommend
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
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
What to expect when we carry out roof structure repairs
Send photos
Photograph the roof from across the street, both slopes if you can, and the loft timbers with a torch. Include the eaves and any cracks just below them. From these we can usually tell sag from spread and whether an engineer is needed.
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.
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.
Is it time for roof structure repairs? Common signs
- Horizontal cracks in the wall just below the eaves or ceiling line
- Daylight through the tiles, or timber that is damp, stained or crumbling
- Ridge line dipping in the middle when seen from the street
Rules 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.
Your roof structure repairs questions
How much will roof structure repairs cost in Portishead?
Guide prices for roof structure repairs in Portishead start from about £310 per rafter, 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 Portishead?
We do. Portishead and the surrounding area are covered, including nearby Nailsea and Clevedon. A free initial assessment from your photos is the first step.
Is the ground in Somerset prone to subsidence?
Somerset mixes Lias clays, Mercia Mudstone, limestone hills and the peat and alluvium of the Levels around Bridgwater, which can settle. The former Somerset coalfield around Radstock and Midsomer Norton left recorded workings. Only an investigation can say why a particular building has moved.
Why are there cracks just below the eaves?
A horizontal crack just below the eaves, along the front or back wall, is a common sign of roof spread. The rafters push the top of the wall outward and the masonry cracks where it hinges. Corroded wall ties can cause similar cracks, so the cause needs checking.
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.
Other structural repairs in Portishead
- Mining subsidence repairs
- Extension pulling away repairs
- Underpinning
- Bowing wall repairs
- Gable end wall repairs
Roof structure repairs near Portishead
Send photos of the roof from the street and the loft timbers at your Portishead property for a free initial assessment and a no-obligation written quote.