United Kingdom · answered by Verika · verified against sources
When is a principal designer required under CDM?
A principal designer is required under CDM 2015 when there is more than one contractor involved in a project, or if it is reasonably foreseeable that more than one contractor will be working on a project at any time. The client must appoint a principal designer in writing as soon as practicable, and in any event before the construction phase begins [5]. For projects with an existing CDM co-ordinator appointed before 6 April 2015, the client must appoint a principal designer by 6 October 2015 unless the project ends before that date [1,3].
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