Truro and the working buildings spread across this part of Cornwall sit in some of the most exposed weather in England, and that matters for the corrugated asbestos cement roofs still common on local stock. On trade units, storage buildings, garage blocks and rural sheds, fibre-cement sheet was the standard covering for decades, and salt-laden Atlantic air weathers it fast. If you own or manage one of these buildings, the duty to look after that roof is yours, and you eventually have to choose between removing it and sealing it in place.
Why a survey comes first in Cornwall
We are a survey-led contractor, and in an exposed coastal county that is not a slogan. The same age of roof can be in very different condition in Truro than it would be inland, so the only honest way to advise you is to get on the roof and look. Before anyone talks numbers, we inspect sheet condition, fixings, sheet laps, rooflights, gutters, any internal signs of leaks, and the state of the structure carrying it all. You then receive written findings and a clear recommendation based on what we actually found.
What the law asks of you
Regulation 4 of the Control of Asbestos Regulations 2012 places a duty to manage asbestos on whoever controls a non-domestic building. You must identify the asbestos-containing materials, assess their condition, record them, and manage the risk. On buildings dating from the late 1950s to the early 1980s, the roof is often the largest asbestos element on the whole site. The duty, though, is about keeping the material safe, not about ripping it out. Where the sheets are sound, a properly applied encapsulation system is a recognised way of meeting that obligation, at far less cost than removal and replacement, and with the building staying in use.
How encapsulation works
Asbestos cement releases fibres as the surface erodes, cracks and weathers, and exposure speeds the process up. Encapsulation locks the surface down. The roof is cleaned using controlled wet methods rather than dry abrasion, worn fixings and flashings are repaired, minor defects are made good, and the whole surface is sealed with a flexible coating made for asbestos cement substrates. The roof becomes watertight, the fibres stay bound into the sheet, and no asbestos waste leaves the site. Encapsulation typically suits a roof where:
- The sheets are weathered but free of widespread cracking or holes
- The cement matrix is still firm, not soft or delaminating
- Fixings, laps and flashings are intact or repairable
- The structure beneath is sound and the building has a working future
When we will advise against it
An honest survey sometimes ends with the answer you did not want. A coating flexes with the sheet it sits on, so if that sheet is already breaking up, no coating will hold it together and the spend is wasted. Where we find brittle, delaminating or badly cracked sheets, structural leaks that keep returning, or a frame that can no longer carry the load safely, we will recommend removal and replacement and put it in writing. We are equally firm on material type. Higher-risk asbestos products such as insulation board or sprayed coatings are a separate category of work that normally requires an HSE-licensed removal contractor. Encapsulation is for sound asbestos cement, nothing else.
What encapsulation changes
One point worth being clear about: encapsulation does not end your duty to manage. The asbestos remains in place, stays on your register, and should be re-inspected periodically. What changes is its condition, moving from a slowly deteriorating liability to a sealed, maintained roof you are properly controlling. If you are responsible for a building in or around Truro, the sensible first step is a proper condition survey, because it gives you the evidence to decide between coating, repair and removal rather than guessing at it.
