What You Need to Know About an Asbestos Cement Roof
If your property was built before 2000 and has a corrugated or flat roof on a garage, shed, or outbuilding, there is a real chance you are looking at an asbestos cement roof. This material was used across the UK for decades — cheap, durable, and widely available. The problem is that when it degrades, gets damaged, or is disturbed during repairs, it can release microscopic fibres that cause serious and often fatal lung conditions.
Property owners, landlords, and facilities managers all need to understand how to identify asbestos cement roofing, where it typically appears, what the genuine health risks are, what UK law requires, and how to handle removal and disposal safely and legally.
What Is an Asbestos Cement Roof?
Asbestos cement is a composite material made by binding asbestos fibres within a cement matrix. The fibres — typically making up around 10% to 15% of the material by weight — give the cement tensile strength, weather resistance, and fire protection. That combination made it extremely attractive to builders throughout the mid-to-late twentieth century.
Production and use of asbestos-containing materials in the UK was effectively ended by a ban that came into full force around 1999. Any building constructed or significantly refurbished before that point may contain asbestos cement in the roof, walls, guttering, or other structural elements.
When the material is intact and undisturbed, fibres remain locked inside the cement and pose a relatively low risk. The danger escalates sharply when sheets are cut, drilled, broken, or badly weathered — actions that release airborne fibres that can be inhaled deep into the lungs.
How to Identify an Asbestos Cement Roof
Visual identification alone cannot confirm whether a roof contains asbestos. Only laboratory analysis of a sample taken by a trained professional can do that with certainty. However, there are characteristics that should prompt you to treat a roof as suspect until proven otherwise.
Visual Characteristics to Look For
- Corrugated profile: The most recognisable form is the wavy, corrugated sheet commonly seen on garages, agricultural buildings, and industrial sheds. Flat sheets also exist, often used as wall cladding or on small extensions.
- Grey or brown colouring: Asbestos cement typically has a dull grey or brownish appearance, often mottled with white flecks from chrysotile fibres embedded in the surface.
- Moss, lichen, and staining: Older sheets frequently show biological growth and weathering stains. This is a strong indicator of age rather than composition, but age is itself a risk factor.
- Surface crazing or fine cracks: As cement ages, it can develop surface crazing. This does not immediately release fibres, but it signals deterioration that warrants professional assessment.
- Age of the building: If the structure was built before 2000, treat any cement-based roof sheeting as potentially containing asbestos until confirmed otherwise.
Modern fibre cement products can look very similar to older asbestos cement. Do not assume a sheet is safe because it looks clean or relatively new. A professional management survey is the only reliable way to distinguish between the two and put a proper management plan in place.
Types of Asbestos Found in Roof Sheets
Three main types of asbestos were used in cement roofing products:
- Chrysotile (white asbestos): By far the most common, accounting for the vast majority of asbestos used in construction. It was used in virtually all asbestos cement roofing produced in the UK.
- Amosite (brown asbestos): Less common in roofing but present in some older products. It has straight, needle-like fibres and is considered more hazardous than chrysotile when disturbed.
- Crocidolite (blue asbestos): Rare in cement roof sheets but found in some older or imported products manufactured before tighter controls were introduced in the 1980s. Regarded as the most hazardous type.
All three types are classified as carcinogenic. There is no safe level of asbestos fibre exposure. The type present affects the level of risk during disturbance, but none should be treated casually.
Where Asbestos Cement Roofing Is Typically Found
Asbestos cement was used across a wide range of building types and locations. Knowing the common spots helps you prioritise where to commission surveys.
- Garages: Pre-2000 domestic and commercial garages are among the most common locations for corrugated asbestos cement roof sheets.
- Garden sheds and outbuildings: Smaller structures were frequently roofed with asbestos cement due to its low cost and ease of installation.
- Agricultural and industrial buildings: Farms, warehouses, and light industrial units used asbestos cement extensively for roofing and wall cladding.
- Soffits and fascias: Flat asbestos cement boards were commonly used under the eaves of domestic and commercial properties.
- Guttering and downpipes: Some older drainage systems incorporated asbestos cement for added strength.
- Flat roof panels: Small extensions, offices, and utility rooms sometimes used flat asbestos cement sheets.
- Wall cladding: Industrial and commercial buildings used asbestos cement cladding in areas exposed to damp or requiring fire resistance.
If you manage a portfolio of older properties, the likelihood of encountering asbestos cement roofing is significant. Supernova Asbestos Surveys covers the full country — whether you need an asbestos survey London, an asbestos survey Manchester, or an asbestos survey Birmingham, professional help is available wherever your properties are located.
Is an Asbestos Cement Roof Dangerous?
The short answer is: it depends on its condition and whether it is being disturbed. An intact, undamaged asbestos cement roof in good condition poses a relatively low risk to building occupants going about their normal activities. The fibres remain bound within the cement matrix.
The risk increases significantly in the following situations:
- The sheets are badly weathered, cracked, or crumbling
- Repair or maintenance work is planned that involves cutting, drilling, or breaking the sheets
- The roof is being replaced or demolished
- Storm damage has cracked or displaced sheets
- Someone attempts DIY repairs without understanding what they are handling
When fibres are released and inhaled, they can lodge permanently in lung tissue. Long-term exposure is associated with asbestosis (scarring of the lungs), mesothelioma (a cancer of the lining of the lungs or abdomen), and lung cancer. These conditions typically take decades to develop after exposure, which is why many people are only now suffering from contact with materials installed in the 1960s, 70s, and 80s.
The HSE is clear that there is no known safe threshold for asbestos fibre inhalation. If you are uncertain about the condition of a roof, commission a professional survey before anyone goes near it.
UK Regulations Governing Asbestos Cement Roofing
The primary legal framework in the UK is the Control of Asbestos Regulations, which set out duties for those who own, manage, or work on buildings containing asbestos. The duty to manage asbestos applies to non-domestic premises, requiring dutyholders to identify asbestos-containing materials, assess their condition, and put a management plan in place.
The HSE’s guidance document HSG264 sets out the standards for asbestos surveys, including the different survey types and what each involves. Choosing the right survey type for your situation is essential — the requirements differ significantly depending on whether you are managing asbestos in situ or planning refurbishment or demolition work.
Licensed vs Non-Licensed Work
Not all work involving asbestos cement automatically requires a licensed contractor. The HSE categorises asbestos work into three tiers:
- Non-licensed work: Some tasks with asbestos cement — such as carefully removing intact sheets using hand tools under strict controls — may fall into this category. The HSE publishes task sheets that provide specific guidance for common non-licensed activities.
- Notifiable non-licensed work (NNLW): Certain tasks must be notified to the relevant enforcing authority even if a licence is not required. Records of medical surveillance must also be kept.
- Licensed work: Higher-risk activities — particularly those involving friable or heavily degraded asbestos materials — must be carried out by a contractor holding a licence from the HSE.
If you are unsure which category your job falls into, the safest approach is to engage a licensed contractor. The cost of getting it wrong — in terms of health, legal liability, and remediation — far outweighs any saving from attempting to classify the work yourself.
Where demolition or significant refurbishment is planned, a demolition survey is a legal requirement before work begins. This type of survey is more intrusive than a management survey and is designed to locate all asbestos-containing materials that could be disturbed during the project.
How to Safely Remove an Asbestos Cement Roof
Whether you are engaging a professional contractor or carrying out notifiable non-licensed work under strict controls, the principles of safe removal remain the same: minimise disturbance, suppress dust, contain the material, and dispose of it legally.
Personal Protective Equipment Required
- FFP3 or P3-rated respirator (EN149 or EN1827 certified) — not a standard dust mask
- Disposable coveralls (minimum Category 5, Type 5/6) with hood
- Single-use nitrile gloves
- Eye protection where there is a risk of splashing or debris
- Rubber boots that can be decontaminated, or disposable boot covers
PPE must be donned before entering the work area and removed carefully in a designated decontamination zone. Used disposable PPE — overalls, gloves, masks — is classified as asbestos waste and must be double-bagged, sealed, and labelled accordingly. Do not take contaminated clothing home to wash.
Step-by-Step Removal Process
- Survey first: Commission a refurbishment or demolition survey before any removal work begins. This confirms what is present and informs the method statement.
- Prepare the area: Erect warning signs and barrier tape around the work zone. Lay 1000-gauge polythene sheeting on the ground below the roof to catch any debris.
- Dampen the sheets: Lightly mist sheets with water or a PVA-based wetting agent before and during work. This suppresses dust without making surfaces dangerously slippery.
- Use hand tools only: Remove fixings carefully using hand tools. Never use power tools — angle grinders, drills, circular saws — on asbestos cement. These generate enormous quantities of fine dust.
- Lift sheets whole: Do not snap, bend, or drop sheets. Carry each one flat and intact to minimise fibre release.
- Double wrap immediately: Wrap each sheet in 1000-gauge polythene, seal with duct tape, and label as hazardous asbestos waste before moving it from the immediate work area.
- Decontaminate: After work, wipe all surfaces with damp rags. Do not dry sweep or use compressed air. Bag all used rags as asbestos waste.
- Clearance inspection: For notifiable or licensed work, a clearance inspection by an independent UKAS-accredited analyst is required before the area is reoccupied.
For professional asbestos removal that meets all regulatory requirements, engaging a specialist contractor is strongly recommended. The risks of DIY removal — to your health and your legal standing — are simply not worth it.
Disposing of Asbestos Cement Waste Legally
Asbestos waste is classified as hazardous waste under UK law. The rules governing its packaging, transport, and disposal are strict, and the penalties for non-compliance — including fly-tipping charges — are severe.
Packaging Requirements
- All asbestos waste must be double-wrapped in heavy-duty polythene (minimum 1000 gauge)
- Each package must be sealed with duct tape and clearly labelled with the asbestos hazard symbol
- Rigid sheets should be wrapped individually and secured to prevent movement during transport
- Smaller debris and PPE should be placed in sealed, labelled asbestos waste bags
Transport and Disposal
Asbestos waste must be transported to a licensed hazardous waste disposal facility. You cannot take asbestos cement sheets to a standard household recycling centre or general skip. The carrier must hold appropriate waste carrier registration, and a waste transfer note must accompany every load.
Fly-tipping asbestos waste is a criminal offence. Local authorities and the Environment Agency have powers to issue significant fines and pursue prosecution. Using a licensed contractor for removal and disposal removes this liability from you entirely.
Should You Replace or Encapsulate an Asbestos Cement Roof?
Not every asbestos cement roof needs immediate removal. If the sheets are in good condition — no significant cracking, no friable edges, no biological growth penetrating the surface — encapsulation or management in place may be the most appropriate short-term strategy.
Encapsulation involves applying a specialist sealant to the surface of the sheets, binding any loose fibres and slowing further deterioration. This is not a permanent solution, but it can extend the safe life of the material while you plan a full replacement programme.
The decision should always be based on a professional condition assessment, not a visual guess from ground level. Factors that typically tip the balance towards full removal include:
- Sheets that are heavily weathered, cracked, or showing significant surface erosion
- Planned refurbishment or change of use that would require disturbing the roof
- Difficulty maintaining safe access for ongoing condition monitoring
- Insurance or mortgage requirements that specify removal
- Planned sale of the property where the presence of asbestos is a material fact
A qualified surveyor can assess the condition of your roof, advise on the most cost-effective approach, and provide the documentation you need for insurance, compliance, and property transactions.
What to Do If You Suspect You Have an Asbestos Cement Roof
If you suspect your roof contains asbestos cement, the steps are straightforward:
- Do not disturb it. Do not attempt to take samples yourself, carry out repairs, or pressure-wash the surface. Any of these actions can release fibres.
- Commission a survey. Contact a UKAS-accredited asbestos surveying company to carry out a management survey. This will confirm whether asbestos is present, identify the type and condition, and recommend a management approach.
- Follow the recommendations. If the surveyor recommends management in place, put a monitoring schedule in place. If removal is recommended, engage a licensed contractor.
- Keep records. Maintain a written asbestos register and ensure anyone who might disturb the material — tradespeople, maintenance staff, tenants — is informed of its presence and location.
For non-domestic premises, these steps are not optional — they are legal obligations under the Control of Asbestos Regulations. For domestic properties, while the duty to manage does not formally apply, the health risks are identical, and the same practical steps apply.
Frequently Asked Questions
How do I know if my garage roof is asbestos cement?
If your garage was built before 2000 and has corrugated or flat cement sheets on the roof, you should treat it as potentially containing asbestos until a professional survey confirms otherwise. Visual characteristics such as a dull grey or brown colour, surface crazing, moss growth, and a corrugated profile are common indicators, but only laboratory analysis of a sample taken by a trained surveyor can give you a definitive answer.
Can I remove an asbestos cement roof myself?
Some limited tasks involving intact asbestos cement sheets may fall into the non-licensed category under HSE guidance, but this does not mean they are low-risk or straightforward. Strict controls on PPE, wetting, waste handling, and disposal still apply. For most property owners, engaging a licensed contractor is the safest and most practical option. Attempting DIY removal without the correct training, equipment, and waste disposal arrangements puts your health and your legal standing at serious risk.
Is an asbestos cement roof dangerous if it is not damaged?
An intact, undisturbed asbestos cement roof in good condition poses a relatively low risk to people in and around the building. The fibres are bound within the cement matrix and are not being released into the air. The risk rises sharply when sheets are cracked, crumbling, or being disturbed by repair or removal work. Regular professional condition assessments are the best way to monitor the situation and act before deterioration reaches a dangerous level.
What does it cost to have an asbestos cement roof removed?
Costs vary depending on the size of the roof, the accessibility of the site, the type and condition of the asbestos cement, and the disposal requirements. A professional surveyor can give you an accurate assessment once the scope of work is confirmed. It is worth getting multiple quotes from licensed contractors, but do not let price alone drive the decision — compliance with regulatory requirements and proper waste disposal are non-negotiable.
Do I need a survey before replacing an asbestos cement roof?
Yes. Before any refurbishment or replacement work begins, a refurbishment or demolition survey is required under HSE guidance and the Control of Asbestos Regulations. This survey is more intrusive than a standard management survey and is designed to locate all asbestos-containing materials that could be disturbed during the project. Starting work without this survey exposes you and your contractors to significant legal and health risks.
Get Expert Help With Your Asbestos Cement Roof
Supernova Asbestos Surveys has completed over 50,000 surveys across the UK, helping property owners, landlords, and facilities managers understand exactly what they are dealing with and what to do about it. Whether you need a management survey to assess the condition of an existing asbestos cement roof, a demolition survey ahead of a replacement project, or guidance on arranging safe removal, our team of qualified surveyors is ready to help.
Call us on 020 4586 0680 or visit asbestos-surveys.org.uk to book your survey or speak to a member of our team. We cover the whole of the UK, with local surveyors available to respond quickly wherever your property is located.