Required and chosen roles
| Category | Characteristic |
|---|---|
| Required role | involvement is compulsory, only the holder is chosen |
| Chosen role | involvement itself follows from a decision |
On a required role the question is not whether to appoint but who will fill it. On a chosen role the question comes first: the client decides whether to have one at all.
That distinction structures the whole fee budget. Required roles are an irreducible cost; the others are a judgment call.
What is required
At least four involvements are not open to discussion, depending on the nature of the project. They follow from the applicable act or regulation.
The architect, whose involvement is mandatory for preparing the drawings and supervising the execution of works requiring consent. This is developed in the article on the architect and mandatory involvement.
Safety and health coordination, where site conditions make it compulsory.
The energy performance officer, appointed under arrangements specific to each region.
Inspection bodies, in fields where third-party inspection is required, covered in the guide on building regulations.
None of those involvements can be set aside by agreement between the parties. They derive from mandatory provisions, as does the Breyne Act within its scope.
What is chosen
Three involvements follow from a decision, and they often make the difference. They are chosen when the project is set up.
The structural engineer and specialist consultants, whose necessity depends on the brief but whose absence shifts the studies onto the architect or the contractor.
The quantity surveyor, whose involvement governs the quality of the bill and hence the comparability of tenders, covered in the guide on measurement and specification.
Voluntary technical inspection, often required by the insurer rather than by law.
A role not entrusted to anyone does not disappear. It is taken on by someone else, often without a corresponding contract, which is the leading cause of uncertainty when a defect arises.
Where the boundaries fall
Three overlap zones produce most disputes. They stem from poorly drawn boundaries between roles.
Between design and execution. The architect designs and supervises, the contractor executes. A defect may stem from either, and the distinction is not always clear-cut.
Between general and construction-stage design. Depending on the contracts, construction drawings are prepared by the designer or by the contractor, and omitting that clause leaves a gap.
Between technical coordination and site management. Two distinct functions that everyday language conflates, and whose allocation must be written.
Those boundaries are set by contract, not by custom. They are covered in the branch on contracts.
What the client retains
A point often neglected, and yet decisive in a separate-trades arrangement. It concerns coordination between the trades.
Whatever is entrusted to no one remains with the client. Coordinating the firms, sequencing the works and arbitrating between trades fall to them if not delegated.
That is precisely what appointing a main contractor changes, and it is also what triggers or removes the protection of the Breyne Act, covered in the article on the single contractor test.
What this means for a professional
Four rules.
List the required roles from the brief stage, since they govern the fee budget.
Allocate the chosen roles explicitly, including to state that they are not being appointed.
Write the boundaries rather than assume them, particularly between general and construction-stage design.
Tell the client what remains with them in separate trades, since they usually do not know.
The articles in this branch
The article on the architect and mandatory involvement covers the monopoly and the incompatibility. The scope of the obligation is set out there.
The article on contractor and main contractor covers the structural choice and its effects. The two arrangements are compared there.
The article on other required participants covers the regulatory roles. Their respective roles are described there.
This article reflects the position of the rules at the date of checking and serves professional orientation. It does not constitute legal advice and does not replace assessment of the individual case.