CDM and Asbestos Control: What Every Contractor Needs to Know Before Setting Foot on Site
If you’re working on any building constructed before 2000, asbestos isn’t a background concern — it’s a frontline legal obligation. The Construction (Design and Management) Regulations, combined with the Control of Asbestos Regulations, create a framework that places real duties on your shoulders before a single tool is lifted. Get it wrong and the consequences range from enforcement action to prosecution — and far worse, preventable deaths.
CDM asbestos control is what every contractor needs to know before work begins. This post breaks down exactly what those duties look like in practice, from pre-construction surveys through to project completion.
What CDM Means for Asbestos Management on Site
The Construction (Design and Management) Regulations set out how health, safety and welfare must be managed throughout a construction project. Asbestos sits squarely within its scope.
Any work that could disturb asbestos-containing materials (ACMs) must be planned, resourced and executed with the same rigour as any other significant hazard. CDM applies to virtually all construction work in Great Britain — from a small domestic extension to a large commercial demolition.
The scale of the project affects who holds which duty, but it does not reduce the obligation to manage asbestos risk. For notifiable projects — those lasting more than 30 working days with more than 20 workers simultaneously on site, or exceeding 500 person-days — a Principal Contractor must be appointed.
That Principal Contractor carries specific duties around co-ordinating asbestos information, ensuring pre-construction surveys are completed, and communicating hazard information to all workers on site. Every contractor in the chain has a role to play, and ignorance of that role is not a legal defence.
The Legal Framework: CDM and the Control of Asbestos Regulations Working Together
CDM doesn’t operate in isolation. It works alongside the Control of Asbestos Regulations, which is the primary legislation governing work with asbestos in Great Britain. Together, these two sets of regulations create overlapping duties that every contractor must understand.
Under the Control of Asbestos Regulations, it is a legal requirement to carry out a suitable and sufficient assessment before any work begins that could disturb ACMs. This means obtaining an up-to-date asbestos survey and acting on its findings.
The HSE’s guidance document HSG264 sets the standard for how surveys should be conducted and what information they must contain. CDM adds a further layer by requiring that this information is shared across the entire project team.
Designers, Principal Contractors, and subcontractors all need to know where ACMs are located and what restrictions apply to working near them. Failure to share this information is a breach of CDM duties — not just poor practice.
Licensing Requirements Under the Control of Asbestos Regulations
Not all asbestos work is equal in terms of licensing requirements. The regulations divide work into three categories, and correctly identifying which applies to your project is a legal obligation — not a judgement call.
Licensed Work
High-risk activities — such as removing asbestos insulation, asbestos insulating board, or sprayed coatings — can only be carried out by a contractor holding an HSE licence. This work also requires notification to the relevant enforcing authority before it begins.
Attempting to carry out licensed work without the appropriate licence is a criminal offence. If you’re not sure whether a task falls into this category, stop and take advice from a competent asbestos professional before proceeding.
Notifiable Non-Licensed Work (NNLW)
Lower-risk tasks that don’t require a licence must still be notified to the enforcing authority. Workers carrying out NNLW must be under medical surveillance and records must be kept.
This category is frequently misunderstood. Contractors sometimes assume that because a licence isn’t required, the work is essentially unregulated — it isn’t. The notification and health surveillance requirements are legally binding.
Non-Licensed Work
The lowest-risk category still requires a risk assessment and appropriate controls. No licence or formal notification is required, but that does not mean the work can be carried out without planning or protective measures.
Getting the categorisation wrong — particularly by treating licensed work as non-licensed — is a serious breach of the regulations and will not be viewed sympathetically by the HSE.
Contractor Duties Before Work Begins
The most common mistake contractors make is treating asbestos as something to deal with if it turns up. That reactive approach is both dangerous and unlawful. Your duties begin before anyone sets foot on site.
Obtain the Right Survey Before Any Intrusive Work
A management survey tells you where ACMs are located and their current condition. It’s designed for routine occupation and maintenance — not for intrusive work.
If your project involves any demolition, refurbishment, or work that will disturb the fabric of the building, you need a refurbishment survey instead. This type of survey is more intrusive by design — the surveyor accesses areas that would normally remain undisturbed, such as wall cavities, above false ceilings, and beneath floor finishes, to identify ACMs that could be disturbed during your works.
This is a legal requirement under HSG264 before any notifiable refurbishment or demolition work. Proceeding without it exposes you, your workers, and your client to serious legal and health consequences.
If the building already has an asbestos register from a previous survey, do not assume it covers your scope of work. Check whether the survey type was appropriate, whether the areas you’re working in were included, and whether the register is still current. Older surveys may not reflect changes to the building or may have used now-outdated methodology.
Review and Act on the Asbestos Register
Once you have a current survey, you must review the asbestos register and incorporate its findings into your Construction Phase Plan. Every worker who could encounter ACMs must be made aware of their location, condition, and the controls in place.
This isn’t a box-ticking exercise. If the register identifies ACMs in areas where you’ll be working, you need a written plan for how those materials will be managed or removed before work proceeds. That plan must be realistic, properly resourced, and communicated to the whole team.
Arrange Removal Before Works Start Where Necessary
Where ACMs are identified in areas that will be disturbed, the safest approach is asbestos removal before the main works begin. This requires engaging a licensed removal contractor for licensed materials, and ensuring that clearance certificates are obtained before other trades move into the area.
Clearance certificates are issued following a four-stage clearance process that includes a thorough visual inspection and air testing by an independent analyst. Without this certificate, you cannot confirm the area is safe for re-occupation or further work.
Managing Asbestos Risk During Construction
Even with the best pre-construction planning, asbestos risk doesn’t disappear once work begins. Contractors must maintain active management throughout the project.
What to Do if Asbestos is Discovered During Work
Unexpected discovery of suspected ACMs is one of the most common asbestos-related incidents on construction sites. Your response must be immediate and controlled:
- Stop all work in the affected area immediately.
- Clear the area and prevent re-entry until the material has been assessed.
- Do not attempt to sample or disturb the material yourself unless you are trained and equipped to do so.
- Notify the Principal Contractor (if you are a subcontractor) and arrange for a competent surveyor to attend and assess the material.
- If sampling confirms asbestos, follow the appropriate removal or management procedure before work resumes.
If you are unsure whether a material contains asbestos, treat it as if it does. A testing kit can be used to collect a sample safely for laboratory analysis, but this should only be done by someone who has received the appropriate training in safe sampling procedures.
Worker Training and Competency
Every worker on a construction site must receive asbestos awareness training if there is any possibility they could disturb ACMs. This is a legal requirement under the Control of Asbestos Regulations — not optional guidance.
Asbestos awareness training covers what asbestos is, where it is likely to be found, the health risks associated with exposure, and what to do if suspected ACMs are encountered. Annual refresher training is considered good practice and is expected by the HSE.
Workers carrying out notifiable non-licensed or licensed work require additional, task-specific training on top of awareness training. Contractors must verify that workers hold the appropriate training certificates before assigning them to asbestos-related tasks — and keep records of those certificates.
Ongoing Re-Inspection of Known ACMs
Where ACMs are being managed in place rather than removed — for example, materials in good condition that are not being disturbed — they must be subject to periodic re-inspection. A re-inspection survey checks the condition of known ACMs and updates the asbestos register accordingly.
This is particularly important on long-running projects where conditions may change over time. A material that was in acceptable condition at the start of a project may deteriorate or become vulnerable to disturbance as work progresses around it.
The Principal Contractor’s Specific Duties
On notifiable projects, the Principal Contractor carries additional asbestos-related responsibilities that go beyond those of individual contractors.
The Principal Contractor must ensure that pre-construction asbestos information is included in the Construction Phase Plan. This includes survey reports, the asbestos register, and any management or removal plans. The Construction Phase Plan must be kept up to date throughout the project and must be readily available to all workers and the HSE if requested.
The Principal Contractor is also responsible for co-ordinating the activities of all contractors on site to ensure that asbestos work does not create risk for other trades working nearby. This requires clear communication, physical segregation where necessary, and documented handover procedures after asbestos removal.
At the end of the project, the Principal Contractor must contribute asbestos information to the Health and Safety File, which is handed to the client. This file must include details of any ACMs that remain in the building, their location, condition, and any management requirements. Future owners, occupiers, and contractors will rely on this information — it is not an administrative afterthought.
Fire Safety and Asbestos: An Overlooked Interaction
One area that contractors frequently overlook is the interaction between asbestos management and fire safety. Asbestos-containing materials were historically used in fire protection roles — sprayed coatings on structural steelwork, fire doors with asbestos cores, and lagging on heating systems.
Disturbing these materials in the course of fire safety upgrades or remediation work can create asbestos exposure risk if not properly managed. If your project involves fire safety works, ensure that a fire risk assessment is carried out in conjunction with your asbestos management plan.
The two must be considered together to avoid creating one hazard whilst managing another. A competent assessor should be able to identify where these overlaps exist and advise on how to sequence the work safely.
Key Duties at a Glance: A Practical Checklist for Contractors
Whether you’re a Principal Contractor on a major project or a sole trader carrying out maintenance work, the following checklist covers the core obligations you must meet:
- Obtain the correct survey type — management survey for routine work, refurbishment survey for any intrusive or demolition work.
- Review the asbestos register before work starts and incorporate findings into your planning documents.
- Identify the licensing category for any asbestos work and ensure the right contractor or worker is assigned.
- Notify the enforcing authority for licensed and notifiable non-licensed work before it begins.
- Ensure all workers have appropriate asbestos awareness training and that records are kept.
- Arrange medical surveillance for workers carrying out NNLW.
- Have a written emergency procedure for unexpected discovery of ACMs.
- Obtain clearance certificates before other trades enter areas where asbestos has been removed.
- Schedule re-inspection surveys for ACMs being managed in place on longer projects.
- Update the Health and Safety File with asbestos information at project completion.
Asbestos Surveys Across the UK: Where We Work
Supernova Asbestos Surveys operates across Great Britain, providing surveys that meet HSG264 standards and give contractors the accurate, actionable information they need to comply with CDM and the Control of Asbestos Regulations.
If you’re planning construction or refurbishment work in the capital, our asbestos survey London service covers the full range of survey types across all London boroughs. For projects in the North West, our asbestos survey Manchester team provides rapid turnaround on both management and refurbishment surveys. In the Midlands, our asbestos survey Birmingham service supports contractors across the region with compliant, UKAS-accredited surveys.
With over 50,000 surveys completed nationwide, we understand what contractors need — clear reports, fast turnaround, and surveyors who know how to communicate findings in a way that supports practical decision-making on site.
Frequently Asked Questions
Do CDM regulations apply to small construction projects involving asbestos?
Yes. CDM applies to virtually all construction work in Great Britain, regardless of scale. The size of the project determines which specific roles must be formally appointed — such as a Principal Designer or Principal Contractor — but the fundamental duty to manage asbestos risk applies to every project where ACMs could be disturbed. Even a small domestic renovation can trigger obligations under both CDM and the Control of Asbestos Regulations.
What type of asbestos survey do I need before starting refurbishment work?
You need a refurbishment survey before any work that will disturb the fabric of a building. A management survey is not sufficient for this purpose — it is designed for routine maintenance and does not involve the intrusive access needed to identify ACMs in concealed areas. HSG264 makes this distinction clear, and proceeding with intrusive work based solely on a management survey is a breach of the regulations.
Who is responsible for asbestos management on a notifiable CDM project?
On a notifiable project, the Principal Contractor holds overall responsibility for co-ordinating asbestos information and ensuring it is communicated to all workers and subcontractors. However, individual contractors and subcontractors also carry their own duties — particularly around worker training, risk assessment, and compliance with licensing requirements. Responsibility is not transferred entirely to the Principal Contractor; every duty holder must fulfil their own obligations.
What should I do if asbestos is found unexpectedly during construction work?
Stop work in the affected area immediately and prevent re-entry. Do not disturb the material. Notify the Principal Contractor if you are a subcontractor, and arrange for a competent surveyor to attend and assess the material. If the material is confirmed to contain asbestos, follow the appropriate removal or encapsulation procedure before work resumes. Treat any unknown material as asbestos until proven otherwise.
Is asbestos awareness training legally required for construction workers?
Yes. The Control of Asbestos Regulations require that any worker who could foreseeably disturb ACMs receives asbestos awareness training. This is a legal requirement, not a recommendation. Workers carrying out notifiable non-licensed or licensed asbestos work require additional task-specific training beyond basic awareness. Contractors must keep records of training certificates and verify competency before assigning workers to asbestos-related tasks.
Work With a Survey Partner Who Understands CDM Obligations
Getting your asbestos surveys right at the start of a project is the single most effective step you can take to manage CDM compliance and protect your workers. Supernova Asbestos Surveys has completed over 50,000 surveys across the UK, working with contractors, principal contractors, and clients on projects of every scale.
Our UKAS-accredited surveyors produce reports that meet HSG264 standards and are written to support practical decision-making — not just to satisfy a regulatory checkbox. Whether you need a management survey, a refurbishment survey ahead of demolition work, or re-inspection of existing ACMs, we can turn surveys around quickly to keep your project on schedule.
Call us on 020 4586 0680 or visit asbestos-surveys.org.uk to discuss your project requirements and get a quote.