Interpretation of Drawings, Plans and Specifications
This domain tests reading a set of drawings well enough to set out and tile without guessing: floor plans, elevations, sections, the finish schedule and the written specification.
What to extract
- Title block and revision cloud: always work from the latest revision; a superseded sheet is a defect waiting to happen.
- Scale and the 'do not scale' note: dimensions written on the drawing override a scaled measurement.
- Finish schedule: tile type, size, reference, joint width, adhesive class, skirting and feature details.
- Setting-out and datum: grid lines, centre lines, expansion joint positions, finished floor level, falls to drains.
- Sections and elevations: build-ups, substrate type, niche and window reveals, movement joints.
Worked example
A plan at 1:50 measures 84 mm between two wall faces. 84 × 50 = 4,200 mm, so the room is 4.2 m clear. The finish schedule calls for 600×600 tiles with 3 mm joints. Check the module: 7 tiles give 7 × 600 + 6 × 3 = 4,218 mm - 18 mm too long. So either the edge tiles are cut to about 591 mm each side, or you use 6 full tiles centred with two 292.5 mm cuts. The reasoning matters: joints consume length, and an exact multiple on the drawing is never exact on site.
Traps that cost marks
- Scaling a PDF and ignoring a stated dimension.
- Reading the plan but not the finish schedule.
- Using structural dimensions as finished dimensions, forgetting plaster or screed thickness.
- Missing the expansion joint locations marked on the drawing.