1. Define the usable dimensions
Record the maximum external length, width and height that the room can accept. Then define the internal bowl length, width, depth, rim width and preferred back angle. A reference image alone does not establish these relationships.
2. Review weight with the actual design
Stone type, wall thickness, bowl geometry and final dimensions all affect weight. Ask for the estimated finished-piece weight after the design is agreed, then have the project engineer or installer confirm the supporting floor and lifting plan. Include water and user loads in the site review.
3. Coordinate waste and tap positions
Confirm the waste fitting, drain opening, outlet position, overflow requirement and maintenance access. Show whether taps are wall-mounted, deck-mounted or floor-mounted, and check spout reach against the final rim and bowl.
4. Check the route before production
Measure doors, corridors, stairs, lifts and turning points. Agree who provides lifting equipment, where the bath can be set down, and how it will be protected between delivery and installation.
5. Approve the interfaces
The final drawing should record the dimensions, drain location, visible faces and any interfaces agreed with the installer. Site waterproofing, structure, plumbing connections and local compliance remain with the relevant project professionals.