top of page


Roles, Responsibilities 

& Liability

A designer is an organisation or individual whose work involves preparing or modifying designs for construction projects, or arranging for, or instructing, others to do this.


Designers can be architects, consulting engineers and quantity surveyors, or anyone who specifies and alters designs as part of their work. They can also include others if they carry out design work, such as contractors or tradespeople eg an electrician who designs the layout and specification of an electrical installation or even commercial clients where they become actively involved in designing in relation to their project.


The Duties of a Designer include:

  • Make sure the client is aware of the client duties under CDM 2015 before starting any design work

  • When preparing or modifying designs: 

    • Take account of any pre-construction information provided by the client (and principal designer, if one is involved) 

    • Eliminate foreseeable health and safety risks to anyone affected by the project (if possible) 

    • Take steps to reduce or control any risks that cannot be eliminated

  • Provide design information to: 

    • The principal designer (if involved), for inclusion in the pre-construction information and the health and safety file

    • The client and principal contractor (or the contractor for single contractor projects) to help them comply with their duties, such as ensuring a construction phase plan is prepared 

  • Communicate, cooperate and coordinate with:

    • Any other designers (including the principal designer) so that all designs are compatible and ensure health and safety, both during the project and beyond

    • All contractors (including the principal contractor), to take account of their knowledge and experience of building designs 


Working as a designer for a domestic client is no different to working for a commercial client. However, the domestic client's legal duties are normally taken on by the contractor (or the principal contractor on projects involving more than one contractor) and the designer must work to them as 'client' under CDM 2015.


Alternatively, the domestic client can ask the principal designer to take on the client duties, although this must be confirmed in a written agreement. Where the project involves more than one contractor and the domestic client does not appoint a principal designer, the role of the principal designer must be carried out by the designer in control of the pre-construction phase.

bottom of page