Duty holders & appointments
What is a designer?
A designer under CDM is anyone who prepares or modifies a design, or arranges for someone to. It is a wider category than architects and engineers, and it is frequently held unknowingly.
Use this diagram+
Free to use on your own site, in training material or in a handout, as long as the credit link stays on it. Paste this where you want the diagram to appear.
<figure>
<img src="https://buildoptix.co.uk/glossary/designer/diagram.svg" alt="designer — diagram from BuildOptix" width="880" height="620" loading="lazy">
<figcaption>
<a href="https://buildoptix.co.uk/glossary/designer">What is a designer?</a> — diagram by
<a href="https://buildoptix.co.uk">BuildOptix</a>
</figcaption>
</figure>A contractor who decides how something will be built, a specialist who details a connection, and a supplier who specifies a product all fall within it. The test is whether they are making design decisions, not what their job is called.
The duty is to eliminate foreseeable risks so far as is reasonably practicable, and to reduce and inform about what remains. It runs through construction, use, maintenance and demolition, not just the build.
Design-and-build is where this bites hardest: the contractor holds designer duties for the parts it designs, which is frequently most of the detail.
What goes wrong in practice
- Design-and-build contractors overlooking their designer duties.
- Risks noted on a drawing rather than designed out where they could have been.
- Maintenance and cleaning access not considered at design stage.