FAQs
CDM, in plain English.
The simple stuff most people don't get told. If your question isn't here, email us; it'll take a minute.
What is CDM and does it apply to my house extension?
CDM is the Construction (Design and Management) Regulations 2015: the law covering health and safety on building projects. It applies to virtually all building work, including domestic extensions and loft conversions. It isn't just for big commercial sites.
What is a Principal Designer? Is that my architect?
Not automatically. The Principal Designer is a specific legal role: the person who plans and coordinates health and safety during the design stage. It can be your architect, but only if they're appointed in writing and actually set up to do it. That's the role we take.
Do I really need one? It's only a small job.
If more than one contractor will be on the job, the law requires the appointment; a builder plus an electrician counts, and subcontractors count even if they come at different times. If you don't make it, the duties don't disappear: on a home project the law hands them to your builder and your designer by default, usually without their knowing or pricing for it, and with no one checking they're done. Commercial clients carry the duties themselves.
Is this the same as the Building Regulations principal designer?
No. The Building Safety Act 2022 created a separate principal designer role under the Building Regulations, and many projects need both. ClearCDM provides the CDM 2015 role only, so you always know exactly what you are buying. Where your project needs the Building Regulations role, we say so plainly, and you appoint it separately.
Does ClearCDM stay involved once building work starts?
That depends on the route you choose at the quote. Through to completion, which suits most projects, keeps us appointed during the works: we coordinate notified design changes and contractor designed elements, and the health and safety file is completed and handed over at practical completion. To start on site ends our appointment when construction begins; it suits projects where there will be no ongoing design work while the project is under construction, or where the contractor or another principal designer will take on the role. Most projects keep designing after work starts, so most clients choose through to completion.
Isn't site safety the builder's responsibility?
Yes. Managing construction work and site safety is the principal contractor's responsibility. The principal designer's role concerns design and pre construction risk. Where our appointment continues during the works, we coordinate the design changes that arise rather than supervise the contractor's work.
Do subcontractors count as contractors under CDM?
Yes. Under CDM 2015 a contractor is anyone who manages or carries out construction work in the course of a business, and that includes subcontractors. They don't need to be on site at the same time: a builder who brings in an electrician for a week has made it a project with more than one contractor, and the Principal Designer appointment is required. HSE's guidance for contractors sets this out.
What do I actually get?
The core CDM outputs for your project: pre-construction information for your builder, the coordination of your design team's risk work, and the core CDM documents, issued before work starts, written for your site, in plain English.
How much of my time does it take?
For most projects, your initial input is one short online form and access for one pre construction site visit. Everyone else involved gets one short form too. If a project needs materially more, we tell you before the fee is confirmed. It's designed so nobody has to chase anybody.
What happens if I just don't bother?
The duties still exist; the law reassigns them. On a home project they pass by default to your builder and your designer, usually unaware and unresourced; if you're a commercial client they stay with you. If something goes wrong on site, the HSE looks at who held the duties and what they did. An unappointed, undocumented project is the worst place for everyone to be standing.
My builder sorts all that, doesn't he?
Half true, in the worst way. If you appoint nobody, the law does hand the duties to your builder by default: unpaid, usually unaware, and with no one checking they're carried. A written appointment puts the role with someone resourced to do it, and your builder gets an information pack instead of a liability.
I'm a landlord and the works are on a house. Am I a domestic client?
No. A domestic client is someone having work done on the home they live in. A buy-to-let or rental property is part of a business, so under CDM 2015 you're a commercial client: the full set of client duties stays with you, including making the appointments in writing. The quote tool prices both the same. Pick commercial client and it will show you what stays with you.
Official guidance
- HSE: domestic clients hse.gov.uk/construction/cdm/2015/domestic-clients.htm
- HSE: commercial clients hse.gov.uk/construction/cdm/2015/commercial-clients.htm
- HSE: designers hse.gov.uk/construction/cdm/2015/designers.htm
- HSE: contractors hse.gov.uk/construction/cdm/2015/contractors.htm