Who do you need on your project, and when?

What this map is doing

It works through the roles in the order a project meets them, then places them on the stages of a project, as the RIBA Plan of Work 2020 names them.

1. Design comes first. Every project needs a designer, or a lead designer where there are several, because it needs drawings to gain approvals and to be priced, whoever produces them.
2. Existing buildings are measured before they are redesigned, so every project except a new house is marked likely to need a measured survey, an accurate drawing of the building as it is now. A new house starts from a survey of the site.
3. Structure: a second storey, a loft floor, a basement, a new house, or a new opening in a load-bearing wall needs its structure designed by a structural engineer, which building control will ask to see.
4. Permissions: whether planning permission is needed depends on the work and on what can be built without a planning application, which the law calls permitted development and which is narrower in a conservation area. A listed building needs listed building consent for any work that would affect its character (Planning (Listed Buildings and Conservation Areas) Act 1990, section 7). Anything that counts as building work needs building control, the council or a registered building control approver, which checks the work against the Building Regulations (Building Regulations 2010, regulation 3(1)).
5. Neighbours: a new wall at the line of junction, the boundary line, work to a party wall, or an excavation within 3 or 6 metres of a neighbour's building needs notice (Party Wall etc. Act 1996, sections 1, 3 and 6). Party wall surveyors are appointed only where a dispute arises, or is deemed to arise (section 10).
6. More than one contractor: the client must appoint in writing a principal designer and a principal contractor under the CDM Regulations 2015, the health and safety rules for building work (regulation 5(1)), and again under the Building Regulations (Building Regulations 2010, regulation 11D(1)). The principal designer (CDM 2015) plans, manages and monitors health and safety in the pre-construction phase; the principal designer (Building Regulations) plans, manages and monitors design work for compliance with the Building Regulations. They are separate appointments. One person can hold both if appointed to both and competent for both, and the client can certify in writing that the CDM principal designer holds the Building Regulations role (regulation 11D(2)). For the CDM 2015 role, ClearCDM's principal designer checker works through the detail.
7. Cost and contract: a quantity surveyor, who advises on cost, and a contract administrator, who administers the building contract, are choices, not legal requirements. The map marks them likely as the construction budget rises, when a funder wants stages certified, or when you want a contract administrator.
8. Stages: each role is placed on the eight stages of a project, from deciding whether to build (stage 0, Strategic Definition) to using the building (stage 7, Use), as the RIBA Plan of Work 2020 names them. The stage map is our own summary of a common pattern for small projects; yours may differ.
9. Time: the map lists only periods set by law. The council has 8 weeks to decide a planning application or a listed building consent application (DMPO 2015, article 34(2); Listed Buildings Regulations 1990, regulation 3(4)), 8 weeks for a lawful development certificate, its written confirmation that the work is allowed without a planning application (article 39(10)), and 42 days for its approval of a larger single-storey rear extension built without a planning application, called prior approval (GPDO 2015, Schedule 2, Part 1, paragraph A.4(10)(c)). A council has 5 weeks to decide an application for building control approval with full drawings, called a full plans application, or a longer period agreed in writing (Building Regulations 2010, regulation 14A(6)). gov.uk still gives a two-month limit, which came from a section of the Building Act 1984 that stopped applying in England on 1 October 2023 (section 16). Whichever way you deal with building control, work may start once two days have passed after the day notice is given, not counting weekends and bank or public holidays (regulations 16(1) and 2). How long design, getting prices from builders and building take varies with each project, so it is not shown. Parallel will publish typical durations from its own projects.