CDM Regulations 2023: What Actually Changed That Year
A lot of people search for the CDM regulations 2023 assuming a new version of CDM landed that year. It did not. The Construction (Design and Management) Regulations 2015 stayed in force throughout, exactly as before. What did happen in 2023 was significant, though: October 2023 brought a new set of dutyholder and competence regulations under the Building Safety Act 2022, and that is almost certainly what people are half remembering. This guide separates the two clearly, so you know what genuinely changed in 2023 and what stayed the same.
Was there a CDM 2023?
No. There is no set of regulations called CDM 2023. The governing regulation across 2023 was, and still is, the Construction (Design and Management) Regulations 2015. CDM 2015 came into force on 6 April 2015 and has not been reissued since. When people talk about the CDM regulations in 2023, they are really talking about CDM 2015, because that is the version that applied to construction projects in Great Britain all through that year and continues to today.
What actually changed in 2023
The real change in 2023 came from a different direction. The Building Regulations etc. (Amendment) (England) Regulations 2023 came into force on 1 October 2023 and introduced a new dutyholder and competence regime under the Building Safety Act 2022. In plain terms, the same idea of named dutyholders that CDM has always used was extended into the Building Regulations, so that clients, principal designers, principal contractors, designers and contractors now carry defined competence and cooperation duties for building regulations compliance as well.
This is why 2023 felt like a year of new rules. It was, but the new rules sat in the Building Regulations, not in CDM. CDM 2015 stayed exactly where it was.
Why CDM and the 2023 changes get confused
The confusion is easy to understand. The 2023 dutyholder regulations deliberately mirror CDM language, using the same job titles and the same emphasis on competence, cooperation and information. Because they arrived hard on the heels of the Building Safety Act 2022 and the wider post-Grenfell reforms, many people assumed CDM itself had been rewritten to match. It was not. The two regimes now run in parallel: CDM 2015 governs construction health and safety, and the 2023 dutyholder regulations govern competence for building regulations compliance.
What stayed the same under CDM 2015
Everything you already know about CDM continued unchanged through 2023 and beyond.
- The duty holders. Client, principal designer, principal contractor, designers and contractors, with the same core duties CDM 2015 set out.
- The core documents. Pre-construction information, the construction phase plan, and the health and safety file where more than one contractor is involved.
- The notification threshold. A project is notifiable to the HSE if construction is scheduled to last longer than 30 working days and have more than 20 workers at any one time, or exceeds 500 person days.
What this means on site
For most ordinary projects, the practical position after 2023 is the same as before. You still work to CDM 2015: a construction phase plan before work starts, risk assessments and method statements, proper welfare, and a health and safety file at the end where the job involves more than one contractor. The 2023 dutyholder regime adds a competence and cooperation layer aimed at building regulations compliance, and it bites hardest on higher-risk buildings, but it does not remove or replace a single CDM 2015 requirement.
Common misunderstandings
The biggest myth is that a new CDM version arrived in 2023 and swept away the old rules. It did not. The second is assuming the October 2023 dutyholder regulations are part of CDM, when they are actually an amendment to the Building Regulations. The third is thinking the changes reduced the paperwork, when the whole direction of travel is towards more evidence of competence, cooperation and who was responsible for what. If anything, 2023 made record keeping more important, not less.
Frequently asked questions
Were there new CDM regulations in 2023?
No. There is no CDM 2023. The Construction (Design and Management) Regulations 2015 stayed in force throughout 2023. The new regulations that year were the Building Regulations etc. (Amendment) (England) Regulations 2023, which introduced a separate dutyholder and competence regime.
What changed in construction regulations in October 2023?
From 1 October 2023 the Building Regulations etc. (Amendment) (England) Regulations 2023 introduced dutyholder and competence requirements under the Building Safety Act 2022. These apply named roles, similar to CDM, to building regulations compliance, with a stricter regime for higher-risk buildings.
Did the 2023 changes replace CDM 2015?
No. The 2023 dutyholder regulations sit alongside CDM 2015 rather than replacing it. CDM 2015 still governs construction health and safety, with the same duty holders, documents and notification threshold as before.
The shortcut
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This article is general guidance for UK construction and is not legal advice. For requirements specific to your work, check current HSE guidance and your own duty holder obligations under CDM 2015 and the Building Safety Act 2022.