Reading of Drawings and Blueprint Interpretation
This domain tests whether you can take a drawing set and extract buildable information: levels, sizes, reinforcement, schedules and revisions.
Reading workflow
Read the title block, scale and revision first; identify grid lines and column centre-lines; read the setting-out and foundation layout; then follow each element from plan to section to detail; finally read schedules and notes and check cross-references.
Schedules
Door and window schedule (mark, size, type, material), beam and column schedules, and the bar bending schedule (BBS) giving bar mark, diameter, spacing, shape, cutting length and total weight. The BBS lets steel be cut and bent without re-reading every bar on the structural drawing.
Levels and notes
GL, SSL, plinth, FFL, lintel and slab-top levels. A slab note such as "125 THK, M25, 10Ø @ 150 c/c BOTTOM BOTH WAYS, COVER 20" means 125 mm thickness, M25 concrete, 10 mm bars at 150 mm centres in the bottom mesh in both directions, with 20 mm clear cover.
Coordination
Architectural drawings show spaces and finishes; structural drawings show frame and steel; services drawings show conduits and pipes. Conflicts are settled in a coordination meeting and issued as a revision.
Worked example
The slab note above sits on a drawing marked Revision C, while the site holds Revision B. Reasoning: Revision C governs; the difference must be checked before cutting steel, and the site copy updated and旧 copies withdrawn.
Traps
Mixing bar diameter with spacing; reading "both ways" as top and bottom; scaling from a JPEG; ignoring "NTS" (not to scale) notes; building from a superseded revision.