1. Start with how it will be used
Describe the intended users and the space, privacy and access they need. Confirm the proposed use with the appropriate authority or professional.
2. Identify site questions
Note access, existing services, trees, slope and relationships to the existing home. These are discussion inputs, not a determination that the site is suitable.
3. Agree the next investigation
List the documents already available and the questions that still need assessment. Confirm what your particular proposal requires before commissioning further information.
This is project preparation guidance. Site suitability, approvals and specialist requirements need project-specific assessment.