Donaldson R F Concrete & Mortar Mix Calculator
Calculate the volume of concrete needed for a slab, footing, or column — plus cement and sand quantities for a mortar mix.
Bag estimate assumes roughly 1 m³ needs about 20 bags of 50kg pre-mixed concrete — actual yield varies by product.
Mortar mix calculator
Mix ratios are common UK bricklaying trade ratios (by volume, cement:sand) — not a single British Standard figure, and real jobs vary by brick type, exposure and mortar additives; always confirm with a structural engineer or the mortar/cement manufacturer for load-bearing or below-ground work. Quantities assume a loose cement bulk density of about 1,440 kg/m³ and a sand bulk density of about 1,600 kg/m³ (Engineering ToolBox), so they are estimates, not exact material orders.
Source: ratio ranges cross-checked against two independently read UK bricklaying trade guides — Beesley & Fildes, "A Guide to Mortar Mix Ratios & Cement Mixing" and MyJobQuote, "Best mortar mix for brickwork" (both last verified 2026-10-08).