What asbestos cement is
Asbestos cement is cement reinforced with asbestos fibres. It was cheap, strong, rot-proof and fire-resistant, so it was made into roof sheets, wall cladding, pipes, gutters, tanks, flues and slates for much of the 20th century. The fibres are held firmly in the cement, which is why it releases fewer fibres than softer materials such as lagging or insulating board, while it’s intact.
Imports of blue and brown asbestos were banned in 1985 and white asbestos in 1999. Sheets made after that use other fibres and look much the same.
Where it was used
- Garage, shed and outbuilding roofs and walls (corrugated or wide-profile sheets)
- Porch, carport and lean-to roofs
- Gutters, downpipes and soffits
- Flue pipes and water tanks
- Roof slates and ridge tiles
- Farm buildings and industrial units
Common condition problems
Asbestos cement weathers slowly. Typical problems are:
- Moss, lichen and surface erosion on the upper face, which roughen the surface over decades
- Brittleness, so sheets crack under load or impact
- Cracks around bolt holes and broken corners
- Leaks at laps and fixings
- Damage from storms, falling branches or fire
Weathered sheets are still usually removable as non-licensed work, but they need more care. Sheets that will be substantially broken up are a different matter (see below).
Is removal licensed?
In most cases, no. HSE lists “removing asbestos cement handled carefully without breaking it up” as non-licensed work, and HSE task sheet A14 covers removing cement sheets and dismantling a small cement structure. HSE’s FAQ notes that most asbestos cement work can be done without a licence, provided workers are trained.
It becomes notifiable non-licensed work (NNLW) where the cement will be substantially damaged or broken up, for example after a fire or flood, or broken up enough to create significant dust and debris. The contractor must then notify before starting, arrange medicals and keep records. See licensed vs non-licensed work.
How trained workers handle it
HSE’s task sheets describe the principles for trained workers:
- Avoid or minimise breaking the sheets. Remove them whole.
- Dampen fixings and remove them, or cut bolts while avoiding contact with the cement.
- Lower sheets to the ground. Don’t drop them or use rubble chutes.
- Never use power tools, abrasive cutting or sanding on the cement.
- Wear suitable RPE and disposable overalls, and decontaminate afterwards.
- Remember the roof is fragile. HSE says cement roofs “are always fragile and cannot bear weight”, so fall prevention has to be planned.
HSE also says the cement-sheet task sheet isn’t appropriate where other asbestos materials, such as lagging or insulating board, are present.
Disposal
Asbestos waste is hazardous waste in England and Wales when it contains more than 0.1% asbestos. HSE’s waste guidance (EM9) says large pieces should be double-wrapped in heavy-duty polythene and labelled, taken to a permitted site, and carried by a registered waste carrier with a consignment note. HSE says intact cement sheets shouldn’t be broken up to fit them into bags.
Householders shouldn’t put it in household waste or a skip. Some councils accept small amounts of bagged asbestos cement from residents, with booking and limits that vary by council, so check with your local council. See asbestos waste disposal.
Leave, repair or remove?
Sound sheets that aren’t leaking can often be left alone and checked from time to time. Small areas of damage can sometimes be repaired, and sheets can be painted by trained workers using HSE methods. Badly weathered, leaking or broken roofs are usually better removed. Our guide on repair, paint or replace covers the decision.
Quick answers
Is asbestos cement dangerous?
It’s lower risk than lagging or insulating board while intact. It releases fibres when broken, cut, drilled, abraded or jet-washed.
Can I tell asbestos cement from modern fibre cement?
Not reliably by eye. A lab test of a small sample will tell you.
Do you remove cement sheets?
Yes. We remove asbestos cement roofs, sheets, gutters, tanks and flues. Ask us for a quote.
This guide is general information, not legal advice. For the law itself, see the Control of Asbestos Regulations 2012 and HSE’s asbestos pages. Not sure what you’re dealing with? Ask us.