Bags of non-shrink cementitious grout for baseplate and equipment grouting — from plate size, formwork extension, grout depth and anchor-bolt pockets. Transparent arithmetic, editable typical values, no code citation (none governs grout consumption).
Formwork normally stands off 75–150 mm past the plate so grout can flow; effective area = (L + 2×ext) × (W + 2×ext).
Set count to 0 to ignore pockets. Use the sleeve/bore diameter, not the bolt.
Typical 11–14 L per 25 kg — verify against your datasheet.
Materials required
bags of grout
Effective grouted area = (plate length + 2 × extension) × (plate width + 2 × extension), or your direct formwork area. Plate volume = area × grout depth. Each anchor pocket is a cylinder, π/4 × diameter² × depth, added to the plate volume. Bags = gross volume ÷ yield per bag, rounded up.
No IS code governs prebagged grout consumption — yield per bag is a manufacturer-datasheet value. The extension, wastage and yield here are editable typical site-practice values; take mixing water strictly from the datasheet, never by guess.
Given: pump bedplate 500 × 300 mm, formwork +100 mm all round, 50 mm grout depth, 4 bolt pockets of 60 mm dia × 300 mm deep, 5% wastage, 25 kg bags yielding 13 L.
Effective area = (500 + 200) × (300 + 200) mm = 0.7 × 0.5 = 0.35 m² → plate volume = 0.35 × 0.05 = 17.5 L
Pockets = 4 × π/4 × 0.06² × 0.3 = +3.39 L → net 20.9 L → with 5% wastage 21.9 L
Bags = 21.9 ÷ 13 = 1.69 → 2 bags of 25 kg
With formwork +100 mm all round: effective area 0.7 × 0.5 = 0.35 m², volume 0.35 × 0.05 = 17.5 L. With 5% wastage and a typical 13 L yield per 25 kg bag: 2 bags. Add anchor pockets if present — four 60 × 300 mm pockets add about 3.4 L.
Flowable grout must travel from the pouring side to the vent side — that needs a working margin beyond the plate. On a 500 × 300 plate, extending 100 mm all round grows the grouted area from 0.15 m² to 0.35 m², more than doubling the grout volume. Measure the actual formwork line, not the plate.
Usually yes for cementitious systems — pockets and sleeves are filled in the same pour or immediately after. Their volume is a cylinder: π/4 × diameter² × depth per pocket. Use the bore/sleeve diameter; a 24 mm bolt in a 60 mm sleeve takes the 60 mm volume.
A compliant non-shrink grout is dimensionally stable — positive expansion in the plastic state, no meaningful shrinkage to compensate for in the quantity take-off. The 5% wastage here covers surface irregularity, plate tilt and formwork leakage. If your datasheet quotes a different yield-per-bag, change it in the form — the arithmetic adapts.
Often used together with this calculator — pick the next step in your design or QA loop.
Deep dive: read the full significance guide — the code clauses, assumptions and site meaning behind these numbers.