Is my garage roof made of asbestos?

It may be. Corrugated grey roof sheets on garages, sheds, carports, lean-tos and farm buildings were often made from asbestos cement, a mix of cement and asbestos fibres. Gutters, downpipes, wall panels and soffits on the same buildings were sometimes made of it too.

The sheets look much like modern fibre cement, so age is only a clue. If the building went up or was re-roofed before 2000, treat the roof as suspect until a sample has been analysed.

Is it dangerous?

Asbestos cement in reasonable condition, left alone, releases few fibres. The risk rises when it is broken, cut, drilled, sanded or scrubbed. Weathered sheets can also shed surface material over time, especially where moss and lichen have taken hold.

So the safest rules for an asbestos cement roof are simple:

do not jet wash, scrape or wire brush it
do not drill, cut or break it
do not try to clear moss from it
do not let children or pets climb on it

Can I stand on it?

Never. Asbestos cement sheets are fragile and can give way under a person's weight without warning. A fall through a fragile roof can cause serious injury or worse. Anyone working on such a roof needs proper access equipment, such as staging, crawling boards or a scaffold, and should not rely on the sheets to hold them.

Who can remove it?

HSE treats careful removal of asbestos cement, without breaking it, as non-licensed work, even when the sheets are weathered. If the sheets are substantially damaged, for example by fire, or will be broken up as they come off, it becomes notifiable non-licensed work, with extra duties for the people doing it. In either case the workers need training and the right equipment, so ask how the job will be done and why it falls in that group.

A small number of garage and shed jobs involve other materials, such as an insulating board lining under the sheets. That may be licensed work, which is one reason to have materials identified first.

What does the removal involve?

A specialist will usually dampen the sheets to keep dust down, undo the fixings and lower each sheet whole rather than breaking or dropping it. The sheets are wrapped in heavy-duty plastic and labelled. Gutters, downpipes and debris on the ground are collected the same way, and the area is cleaned with a suitable vacuum or wet wipes, never a broom.

Ask whether the price includes a new roof, or whether you need a roofer or builder for that. Some specialists take off the old roof only.

Can the roof be left where it is?

If the sheets are sound and nobody needs to work on the roof, leaving them alone is a reasonable choice. Some owners have sound sheets sealed with a suitable coating or covered over, though any of these options should be discussed with a specialist first, because cleaning a roof before coating it can itself disturb the surface. Removal tends to make sense when the roof leaks, the sheets are cracked or the building is being rebuilt.

What happens to the sheets?

They are hazardous waste. A specialist removing them should take them away using a registered waste carrier to a permitted site, and give you the paperwork. Do not leave sheets in a front garden or skip, and never put them in a household bin.

If you are thinking of disposing of a small amount yourself, read your council's guidance first. Hertfordshire County Council and the London Borough of Enfield each set their own rules.

What about a block of garages?

Garages owned by a landlord, a housing association or a residents' company are a different matter. Where garages form part of the shared areas of a residential block, the duty to manage asbestos can apply to them, so the owner should already have a record of any asbestos there. Tenants and leaseholders should speak to the owner before any work.

What should my enquiry say?

the postcode and the type of building
the rough size of the roof, or the number of sheets
whether the sheets are cracked, broken or covered in moss
whether access is clear, or through a house or over a fence
whether you also need a new roof

What happens once it is sent?

Sending an enquiry is free and commits you to nothing. Where a specialist covers your postcode, they agree the job and terms with you directly.

Who you will hear from

We pass your enquiry to one local asbestos specialist, if one covers your postcode. It is never sent to a list of companies. If nobody covers your postcode, we will tell you and will not pass your details on.