CDM: whose job is it anyway — and does it even apply to you?
Let’s be honest: say “CDM” to most clients and they picture a major new-build, cranes, hard hats, a site manager with a clipboard. Not the office refurb. Not the warehouse mezzanine. Not the shop fit finishing next month. It feels like “someone else’s regulation,” right?
Here’s the catch: the Construction (Design and Management) Regulations 2015 apply to every construction project in Great Britain — whatever the size, whoever the client, notifiable to the HSE or not. The moment you commission construction, refurbishment, maintenance or demolition work, you’ve got duties under CDM. Realising that on day one, rather than week six, is where most of our clients trip up.
A quick thought
If your project started on site tomorrow, could you say with confidence, not assumptions:
• You know who your Principal Designer is?
• You know whether you need a Principal Contractor?
• A Construction Phase Plan actually exists?
• Competent people were involved before the design was finalised, not after the contractor turned up?
• You could show the “suitable arrangements” you’ve made, if HSE asked?
Confidence beats crossed fingers. Every time.
“We’re not notifying the HSE, so it doesn’t apply…”
This is the myth that catches out so many organisations. A project only needs to be notified to the HSE if it will last more than 30 working days with more than 20 workers on site at once, or add up to more than 500 person-days. Surely, below that, CDM doesn’t apply?
Not quite. Notification is just a paperwork trigger for the HSE — it has nothing to do with whether the regulations apply. They already do. Every construction project has a client with duties. Any project with more than one contractor needs a Principal Designer and a Principal Contractor. Small and short doesn’t mean exempt. It usually just means the risk is easier to miss.
It’s not the big stuff , it’s the gaps
When it goes wrong, it’s rarely dramatic. It’s the small things nobody pinned down:
No one’s been formally appointed Principal Designer.
Client duties are assumed to sit with “whoever’s doing the work.”
A consultant is brought in once the Contractor’s already mobilised.
Pre-construction information was never pulled together.
Domestic clients assume none of this touches them.
Individually, none of these looks huge. Together, they leave the project and the client exposed.
Who’s who under CDM
This doesn’t need to be complicated. It just needs clarity on five roles:
Client: Commissions the work. Must ensure suitable time and resources are allowed, the right duty holders are appointed, and welfare facilities are provided.
Principal Designer: Required whenever more than one contractor is involved. Plans, manages and monitors the pre-construction phase, and coordinates health and safety through design decisions before anyone breaks ground.
Principal Contractor: Runs the construction phase, coordinates every contractor on site, and prepares the Construction Phase Plan.
Designers: Architects, engineers, anyone specifying how something is built. Responsible for eliminating or reducing risk at the design stage, not leaving it for site to solve.
Contractors and workers: Carry out the work safely, following the plans and information put in place above them
In other words: someone always holds the client’s duties, even when the client hasn’t realised it yet.
Domestic clients aren’t off the hook either
Homeowners having an extension or loft conversion built rarely think of themselves as a “CDM client.” Legally, they’re usually not expected to carry those duties personally they pass automatically to the Contractor, or to the Principal Contractor and Principal Designer where there’s more than one Contractor. But the regulations still apply to the project itself. Someone still has to hold those duties. Assuming otherwise doesn’t remove the risk it just leaves it unmanaged.
Five questions to chew on with your project team
Do we know, project by project, who our client duties actually sit with?
Has a Principal Designer been appointed before design work started?
Will there be more than one contractor on site at any point?
Where’s our pre-construction information and has it actually been shared?
If HSE walked onto site tomorrow, could we show our arrangements?
These conversations tend to uncover easy wins long before anything goes wrong.
Five practical actions to start this week
Map your projects: which ones involve construction work, and who the client is on each.
Appoint early: bring your Principal Designer in at feasibility stage, not after planning permission is granted.
Check the headcount: work out whether you’ll have more than one Contractor on site, that’s your trigger for a Principal Designer and Principal Contractor.
Pull together pre-construction information before you ask anyone to quote, not after.
Talk to us before the tender goes out, not after the Contractor’s already booked in.
None of this is hard. Together, it builds real assurance and a much stronger starting position.
The bottom line
CDM was never really about paperwork or project size. It’s about making sure the right people make the right decisions at the right time, ideally before the design is finished, not after the diggers arrive. The best clients don’t ask “is this notifiable?” They ask “who’s holding these duties, and have we appointed them yet?”
We can help you get this right from day one!
Please do not hesitate to contact Colin on 07799 656303. Alternatively, you can drop us a message at hello@influentialmg.com.
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