The design programme
The order of dependencies
Section titled “The order of dependencies”Design is not a set of parallel tasks: there are steps that can only start when the previous one is done.
The typical chain:
- Site data and design brief → without them there is no meaningful concept.
- Architectural concept → the structure and the services start from it.
- Structural concept and spans → they bound the service routes.
- Services concept → it gives the structural penetrations and the demands on the build-up.
- Finalising the build-ups → this needs the fire and energy requirements.
- Detailed design in every discipline.
- Shop drawings.
If any step is incomplete, the next either stops or is built on an assumption.
Where the delay arises
Section titled “Where the delay arises”Waiting for a decision
Section titled “Waiting for a decision”The designer asks and gets no answer. The most common cause, and the one least within the designer’s control.
Missing data
Section titled “Missing data”Ground investigation, utility data, survey. Obtaining these takes lead time.
Late change
Section titled “Late change”Amending a stage already closed affects several disciplines.
Authority lead times
Section titled “Authority lead times”Permitting, specialist authority input.
How it can be managed
Section titled “How it can be managed”Signal the decision points
Section titled “Signal the decision points”The designer should flag in advance when a decision will be needed and what it is. That gives the client time.
Start data gathering early
Section titled “Start data gathering early”Ground investigation, utility data: they can be started in the first week and take weeks.
Close each stage
Section titled “Close each stage”A stage has to be closed before the next starts. The “it’ll sort itself out as we go” attitude is particularly expensive with a prefabricated structure.
A buffer before manufacture
Section titled “A buffer before manufacture”Leave time for the last check before manufacture.
The realistic expectation
Section titled “The realistic expectation”A design cannot be sped up indefinitely, because the steps build on one another. What can be sped up is the decision time and the data gathering — in other words the client’s side.
The point
Section titled “The point”The programme is an order of dependencies, not a list of deadlines. Delay generally arises where the design is waiting for something.