The difference between ‘planning’ and ‘detailed’ drawings
There are two fundamental parts to architectural drawings. ‘Planning’ and ‘Detailed design’. The concept, appearance and layout design is all undertaken en-route to producing ‘Planning’ stage drawings, named due to the usual need to apply for planning permission. The technical side of construction information is tackled in the ‘Detailed Design’ stage, usually after securing planning consent.
The planning drawings are the principle output from the briefing, sketching, designing and developing stages. These drawings are primarily used to present the proposal to the local Planning Authority to seek permission. They show external materials, window and door sizes, materials and shapes etc but don’t typically explain how the walls and such should be constructed.
On some small or simple projects the work is straightforward enough not to need any further detailed construction information. A quality and experienced builder can work from ‘Planning’ drawings only, working out all the details themselves, with some site questions answered by the clients directly. They will use their knowledge and experience to build the building to the planning drawings. It can be a sensible approach to avoid paying for unnecessary drawings or delay. The builder can appoint a structural engineer to provide sizes and calculations for enlarged openings, and can liaise with Building Control directly. However post October 2023 this will mean the contractor will default to assuming the role of ‘Principal Designer’ as well as ‘Principal Contractor’ which comes with some more stringent legally required duties that need to be discharged before a final certificate from building control can be issued..
Technical or detailed design stage (RIBA stage 4) is where construction techniques, material choices and in-depth information is worked up and illustrated. It involves researching and applying in-depth knowledge of building methods and the building regulations.
Below you can see a few sample drawings showing cut-throughs of critical building constructions at a larger scale so that the layers can be properly seen and described.
As part of the construction package it is useful also to include an outline electrical layout so decisiions on socket positions and light switching can be done before works starts on site.
Internal room elevations also allow the amount of tiling, radiator positions, heights of shelving etc all to be designed and agreed, so that a complete picture can be put to the contractors.