A roof survey on a slate roof is money well spent. Slate is a wonderfully long-lived covering — Welsh slate has been known to last well over a century — but it fails quietly, and by the time water appears on a ceiling the problem has usually been developing for years. A good surveyor will find those problems early. What they will not do is climb over your garden furniture, guess at a leak you never mentioned, or work on a roof without knowing what they are standing on. A little preparation makes the whole exercise safer, quicker and far more useful.

Clear the Way Before Anyone Arrives

Access is the most common reason a survey runs long or gets cut short.

• Move vehicles off the drive and away from the elevation being inspected, so a ladder can be footed properly.
• Unlock side gates, remove planters and bins, and clear the path around the whole house — not just the front.
• Tie back climbing plants. Wisteria, ivy and Virginia creeper hide slipped slates, splits in flashing and cracked mortar.
• Keep pets and children indoors.
• Clear the loft hatch and create a safe route through stored items, so the surveyor can move about without compressing insulation.

If the loft is boarded or full to the rafters, say so in advance. A surveyor who cannot get inside is working with one hand tied behind their back.

Note the Problems You've Spotted Already

Your observations are evidence. Write them down, with dates and photographs where you can — a damp patch that appears after a south-westerly gale tells the surveyor something quite different from one that spreads slowly all winter.

• Damp patches, bubbling paint or tide marks on ceilings and chimney breasts.
• Individual slates on the ground or in the gutter after storms.
• Daylight visible between slates from inside the loft, or water staining on rafters and battens.
• Crumbling mortar on the ridge, or beneath the slates where an older roof was torched with mortar.
• Water running down the inside face of a gable wall, or gutters overflowing after moderate rain.

Mention previous repairs too, however long ago, and who carried them out if you know.

Ask About Method Statements, Insurance and Access

Before you agree to a visit, ask how the inspection will actually be carried out. On pitched slate roofs a competent contractor should talk you through a written risk assessment and method statement — often shortened to RAMS — covering the working at height regulations, ladder stability, roof ladders or crawler boards, edge protection, and how they will avoid walking directly on fragile slates. Old slate becomes brittle, particularly in cold weather, and a heavy boot in the wrong place can turn a small repair into a large one.

Also confirm:

• Public liability insurance, and employers' liability if they are bringing staff.
• Whether the person surveying is the person who will price and carry out the work.
• Whether a drone or pole camera will be used first, and whether anyone will still go up close to check flashings and mortar joints.
• Whether the report will include photographs and a prioritised schedule of repairs with costs.

Get the fee, or the fact that there is no fee, confirmed in writing.

Understand Your Slate and Your Property's Status

It helps to know what you are dealing with. Period roofs commonly use Welsh slate, Westmorland green, Delabole or Scottish slate, often laid in diminishing courses with larger slates at the eaves and smaller ones towards the ridge. Repairs should match thickness, size and colour reasonably closely, and should never rely on cement where lime mortar was used originally — lime lets the roof breathe and move.

Check whether your home is listed, in a conservation area, or subject to an Article 4 direction. Listed building consent may be needed even for modest changes, such as replacing slates with a different material or altering a chimney stack. If bats use the roof — and they frequently do in older properties — they are legally protected, and work may need a specialist survey and a licence before it begins.

Think About Timing, Weather and Wildlife

Book the survey for a dry, calm day if you can. Rain obscures staining and makes wet slates treacherous, while frost makes old slate especially brittle. Late spring and summer are ideal, but bear in mind that birds nest between March and August, and disturbing an active nest is an offence.

Allow a couple of hours, be available to answer questions, and ask to be shown what has been found in the loft if you can get up there safely.

What a Good Survey Should Leave You With

By the end of a well-prepared visit you should have a clear picture rather than a vague worry. Expect a written report with photographs, a note of anything urgent affecting weathertightness, a list of items to monitor over the next year or two, and costed options so you can plan rather than panic.

Ask which repairs are genuinely urgent and which can wait, and how the work would be staged if the budget is tight. If anything is unclear, ask again before the surveyor leaves the drive. A survey is not a sales pitch — it is a maintenance plan for a roof that, looked after properly, may well outlast us all.