Measurement, Quality Control and Work Documentation
Core concepts
You must be able to measure your own work, prove it meets specification, and record it so the quantity surveyor and the supervisor can be paid and can defend the work.
Measurement
Units follow the item: linear work in m, walling and plaster in m2, concrete and excavation in m3, reinforcement in kg, and individual items such as lintels, doors or manholes in number. Wall thickness is described in the item description, so the measured area is the face area, and the mortar is not measured separately because it is included in the masonry rate. Decide and record how openings and returns are treated. Common practice in public-works bills is to ignore very small openings, often those under about 0.1 m2, and deduct larger ones; confirm the threshold against the project specification and preambles, because the figure varies between documents, and apply whatever rule is stated consistently.
Quality control
Inspect against the specification: joint thickness, plumb and level within tolerance (typically a few millimetres per storey, checked with a 2 m straight edge and level), bond and coursing, mortar mix, slump of concrete, cube results at 7 and 28 days, curing records, plaster thickness and finish. Test and inspect before covering up: an inspection request must be raised before work is concealed.
Documentation
Site diary (weather, labour, plant, deliveries, instructions), goods received notes and delivery challans, material requisitions, inspection checklists and snag lists, progress reports, variation orders, concrete cube and slump records, test certificates, and as-built drawings. Record every instruction from the engineer, especially verbal ones, in writing the same day.
Traps in questions
Measuring to the centre line when the item is measured to the face, double counting an item, forgetting wastage when ordering, and accepting a verbal variation without a written record.
Worked rule of thumb
A wall 12 m long, 3 m high, with one 1.2 m x 2.1 m opening: gross area = 36.00 m2, deduct 2.52 m2, net = 33.48 m2 of masonry.