Construction Calculators (Page 2)
Area, materials, paint and other construction calculations.
Concrete Volume Calculator
Estimate concrete volume and weight from length, width and thickness (or cylinder diameter and height).
Staircase Calculator
Enter floor height, target rise and going to compute the number of steps, actual rise, total run, stair angle and a Hong Kong residential compliance check.
Mortar Mix Calculator
Enter the mortar volume and cement-to-sand ratio (e.g. 1:4) to instantly calculate the cement bags (50 kg), sand volume and total weight for brick, plaster and stonework quoting.
Formwork Area Calculator
Select element type (column, beam, slab), enter section size, length and count to compute the total timber formwork area for concrete works.
Soil Excavation Calculator
Enter the pit length, width, depth and slope ratio to calculate the in-situ excavation volume, the loose (swollen) volume and the backfill required — useful for site excavation, muck-away and refill estimating.
Concrete Weight Calculator
Enter concrete volume and density (normal, lightweight or heavy) to compute member self-weight (kg/tonnes); optionally add rebar ratio for total weight, for lifting, transport and floor-load estimates.
Plaster / Render Area Calculator
Enter wall length and height, deduct openings, and set coats and thickness to estimate net plaster area and mortar volume for rendering and levelling.
Grout Calculator
Enter the tile size, joint width, joint depth and tiled area to calculate the grout (joint filler) volume and weight for floor and wall tiles or stone.
Drainage Slope Calculator
Enter the drainage length and slope percentage to compute the fall (mm) and slope ratio (1:N), and check against Hong Kong's common minimum 1:80 (≈1.25%) requirement.
RC Slab Rebar Calculator
Enter slab size, main and distribution bar spacing and diameter to compute bar counts and total steel weight (kg) using the d²/162 per-metre formula for slab reinforcement takeoff.
Floor Screed Calculator
Enter floor area and screed thickness to compute the cement-sand mortar volume, then estimate cement bags and loose sand by mix ratio for home or site levelling.
Concrete Aggregate Mix Calculator
Enter concrete volume and mix ratio (e.g. 1:2:4) to work out the weight of cement, sand and gravel (aggregate) and the number of cement bags — handy for on-site mixing and delivery estimates.