Why there is no single standard allowance
Fees reflect professional time, overheads and expenses; changes to the brief or unexpected conditions can affect the work required. Read a fixed fee alongside its assumptions and exclusions. [1]
Ask which discoveries or instructions would require an additional fee, and how approval for that extra work would be obtained.
Request a project-specific fee and programme that explain the deliverables and the work needed to produce them.
What affects the workload?
The scope may involve straightforward calculations or a broader assessment with surveys, testing and site attendance. [2]
Temporary works need their own design consideration and planning, separate from the finished structure. [3]
Ask who provides each service and where responsibility passes between the engineer, contractor and any specialist designer.
A concealed condition can also prevent a final answer. A visual structural inspection may need to be followed by opening-up or a foundation investigation, rather than an immediate calculation based on assumed construction. [4]
For your comparison checklist, ask each engineer to identify:
- the elements and connections covered by the price;
- the surveys or information required before design starts;
- the allowance for design options and agreed revisions;
- responses to building-control comments and construction queries;
- site visits, travel, reporting and any separately priced services.
Ask for a sequence, not just a delivery date
Request dates for the initial assessment, any investigations, the coordinated design issue and answers to outstanding queries. Ask what must be supplied before each stage can proceed. This gives you a way to distinguish a waiting period from active design work without assuming that a quoted issue date also means approval.
Ask your building-control body when it needs the structural package and how queries will be resolved. Build those steps into the programme separately from the engineer's issue date, and identify who will provide any additional information requested before the affected work starts.
Keep the design stable enough to complete
Agree the main layout before asking for a final package, while leaving space for changes arising from engineering advice. Clear drawings and specifications give the builder a firmer basis for pricing than an unresolved concept. This is one reason to compare the completeness of the proposed service, not simply the headline design fee. [5]
Do not ask the team to make an unsafe programme fit an already-booked demolition date. HSE requires structural alteration to be planned around stability, including the temporary condition during the works. [6]
Confirm what happens when the brief changes
Request written approval of additional services before they are undertaken, except where urgent safety action is necessary. A useful instruction identifies the change, its reason, the additional output, the price basis and the effect on the programme. Keep this record with the original appointment so that the final invoice can be checked against work actually authorised.