A modern roof survey asks whether the covering is sound and, if it is not, what should replace it. A survey of a period roof begins somewhere else. The question there is how much of the existing roof can stay, because on an older building the tiles, slates or stone slabs are part of what makes the building what it is. Stripping them and starting again can cost far more than patient repair, and on a listed building it may need permission you do not yet have.
That changes the order of work. Before anything is priced we need to know the materials, how they were laid, where the roof has been altered before, and which parts are failing for a reason that can be dealt with. The answers decide the repair, the consent route and the people who must be asked.
Around Worthing and the villages behind it, period roofs run from slate on seafront terraces to clay peg tiles on flint cottages and, further inland, Horsham stone slabs. Below we set out how we approach each, what consent rules apply, and what a useful report contains. Our general survey work is described on the roof inspections and surveys page.
Why age alone is not a verdict
On an old roof, age is not automatically a fault. The 60-year life that Marley quotes for modern clay tiles is a brochure figure for new product, and Building Conservation Directory calls it unreliable when applied to peg-tile roofs that have stood for centuries. The more useful question is condition: which parts are sound, which are worn out and which merely look tired.
We therefore survey in layers. First the covering itself, looking at surface decay, tiles that have lost their nibs, cracked or slipped slates and the nails or pegs holding them. Then the junctions, where chimneys, valleys and abutments meet the slopes and where earlier repairs were often made with whatever was to hand. Then the structure below, seen from the loft: rafters, purlins, wall plates and the timber that carries the slope.
Earlier repairs tell a story
Period roofs accumulate patches. You may find a few concrete tiles among clay, a run of bedded mortar where a lead flashing once sat, or a section re-laid at a different spacing. Those changes matter because they often sit exactly where water has been entering. A survey that maps them shows both the failure and the likely cause.
Access can be awkward. High, steep or fragile roofs may be better viewed by drone or pole camera than by walking on them, since a boot on old slate or stone can crack it. Our comparison of drone and ladder surveys explains when each suits.
Old timbers settle over generations, and past owners may have propped or packed them. Look for the signs when you stand in the loft, and let the surveyor explain which of them are historic quirks and which are live defects. A dip along a ridge line is not necessarily new, or a fault, but it should be measured and photographed so that any later movement shows up.
The aim is to establish whether repair is possible. Where it is, the report names the repair. Where it is not, it spells out what has to go and why.
Matching materials and methods
Repairing a period roof well means matching more than appearance. Size, thickness, colour and texture of each slate or tile, the way courses shrink towards the ridge, the lap, the nails and the mortar all affect how the roof sheds water and ages beside the original. A repair that looks right on the day can look wrong within a few seasons, or can trap water against old material.
Modern fixing standards need thought here. According to Marley, BS 5534 favours mechanical fixings for tiles and for ridge and hip fittings, while its 2018 amendment accepts that those recommendations may not suit heritage roofs and points owners towards the planning authority and conservation specialists. For us that means the survey records how each element is fixed today, and the proposal says where it follows current practice and where it deliberately departs.
What like for like really means
The phrase deserves pinning down. It means the same material, in the same form, laid in the same manner, not the nearest modern look-alike. Concrete interlocking tiles are not a match for hand-made clay. When a roofer says a product matches, ask what the originals are, where the replacements come from and how they will be laid.
Reclaimed material holds a particular place. It can be the best match, since it carries the same weathering, but it came from somewhere. A responsible supplier can tell you where, and a survey report should say if matching stock is likely to be hard to find.
Clay, slate and stone each have their own detail. Our pages on slate in a conservation area and repairs to listed roofs go into the materials they cover.
Consent: what is needed and from whom
Consent depends on the status of the building, and status is the first thing to confirm. For a listed building, the statute makes it an offence to alter it in a way that affects its special interest unless the works are authorised. Adur & Worthing Councils include repairs in non-matching materials among works that call for listed building consent, yet add that plain upkeep is left alone until an owner proposes a change. Their listed building consent guide is worth reading before you commission anything.
Keep a file of the paperwork. Consent decisions, photographs taken before work and the surveyor's report together form the record of what the roof was, which helps at sale and for any later application.
The South Downs National Park Authority separates mending from replacing: a small repair with matching material, done in place, needs no listed building consent, whereas removing historic fabric that gives the building its character does. No four-year time limit protects unauthorised work to a listed building from enforcement.
Conservation areas and Article 4 directions
A conservation area does not mean you always need permission to re-roof. Some have Article 4 directions that take away permitted development rights, though. Both Old Shoreham and Kingston Buci have a direction made in early 2023. It ends the right to change roof coverings on houses whose front faces a road or a right of way. Worthing's Warwick Gardens direction does something similar for roof slopes on road or open-space frontages. Ask the Adur & Worthing planning team before ordering materials.
Churches and monuments
Churches in use under the Church of England sit outside listed building consent and answer to the faculty system. Roman Catholic and Methodist churches in use follow procedures of their own, as do Baptist Union and United Reformed ones. Other denominations, and any church that has closed, come under normal consent. A scheduled monument needs its own consent from the Secretary of State, whatever its use.
Horsham stone and other stone slates
Roofing slabs of Horsham stone are split from a calcareous sandstone and laid in random sizes, with the heaviest courses low on the roof and the finest at the top. The Stone Roofing Association sets out a double-lap method and a single-lap method that belongs to this stone alone, where Welsh slate shadows set in mortar make the joints weatherproof. A survey has to work out which was used, since repairs have often blended the two.
Where these roofs survive they tend to cover the older buildings of the Downs and Weald. Horsham District Council's appraisals record slab roofs in large numbers at Steyning, in use at Henfield, and on Church Street at Storrington. The Adur appraisals call them uncommon along the coast, with examples at the Old Rectory in Kingston Buci and on the church at North Lancing.
Reuse comes first
The Association advises salvaging and relaying what the roof already has before looking elsewhere. Slabs lifted from other buildings, which it says drives the destruction of old roofs, should be a last resort, and new Horsham slabs should fill any gap where suitable ones can be had. A report in 2019 described a crisis in supply, so a survey should be frank about how much stone the roof can supply for itself.
Steyning's council appraisal singles out re-laying slab roofs with mortared joints as a poor repair. Switching from single to double lap changes the loading, so the structure has to be reviewed, and the Association says building control approval or a church faculty follows, along with listed building consent for listed buildings. Its Horsham stone guide sets out the detail, and our Horsham stone roofing page covers the repairs. Where the loading is in doubt, a structural engineer is the person to ask.
What the report records, and what it costs
A report on a period roof should read like a condition record. It should identify the covering, record how it was laid and state the building's status: listed, inside a conservation area, within the South Downs National Park or none of these. It should map faults on a simple roof sketch with numbered photographs, separate urgent repairs from those that can wait, and describe what each involves.
It should also say what remains unknown. Without lifting covering you cannot always see the battens, the underlay or the condition of the fixings. A responsible survey flags where evidence runs out and proposes opening a small area to find out, rather than guessing in either direction.
Questions to put to the surveyor
Ask what the roof is made of and whether any of it is original. Ask which faults are letting water in and which are cosmetic. Ask which proposed repairs need consent, from which body, and who will apply. Ask how the work would be fixed and how the original was. And ask what happens to old material coming off: reusable stone, slate and clay is worth keeping for future repairs.
Cost
A period roof takes longer to survey than a standard one, so expect it to sit towards the upper end of the usual range. MyBuilder, updated 21 August 2026, gives a typical UK range of £150 to £500 for a roof inspection, and our page on what a roof inspection costs explains what moves the figure. Checkatrade, last updated September 2026, puts stone slate roofing at around £160 to £210 per m², though not for Horsham stone specifically. The written quote follows the survey. If panels are planned for an older roof, read the roof survey before solar first, and for evidence from inside the building see checking your loft.
