Concrete Wall Calculator — m, cm to m³, bags, cost
How to use this calculator
Pick a wall layout, type length/height/thickness in metres, centimetres, or millimetres, and deduct openings. The output sizes the ready-mix delivery or bag count, the formwork panels and ties for the contact area, and the rebar grid before you call the supplier.
Cost — pick ready-mix delivery per m³, 50 kg bags, or 25 kg bags. Select your currency (EUR, PLN, CZK, SEK, etc.) in the settings below.
Reinforcement — horizontal and vertical rebar diameters 8-20 mm with spacing 100-300 mm per EN 1992-1-1 (Eurocode 2), including lap splices.
Labor — rate per m² of formwork (contact area), per m³, or flat price. Grand total sums all active sections.
Saved Calculations
| Time | Config | Length | Vol m³ | Concrete | Rebar | Rebar cost | Labor | Total |
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How to Calculate Concrete for a Poured Wall
Pick the wall layout that matches your pour — a single wall, an L-shape (two walls at a corner), a U-shape (back plus two returns), or a closed rectangle. Enter length, height, and thickness in metres, centimetres, or millimetres, then deduct door and window openings so the volume reflects the concrete actually placed. Thickness drives both volume and structural capacity: 20 cm is typical for single-storey foundation walls, 25–30 cm for two-storey or retaining walls. For plain volume without formwork and rebar, the simpler concrete volume calculator covers slabs, footings, and rectangular pours.
Wall Volume Formula
Volume = Total Wall Length × Height × Thickness − (Openings × Avg Width × Avg Height × Thickness), in m³. Concrete density is about 2 400 kg/m³, so a tonne is roughly 0.42 m³. Formwork (contact) area is both faces of the wall, 2 × Length × Height — that figure sizes formwork panels, ties, and most of the labor. Add 5–10% extra for spillage, over-excavation, and form deflection. For bagged pours, cross-check bag counts against the dedicated concrete bag calculator.
Reinforcement per Eurocode 2 (EN 1992-1-1)
Walls carry both horizontal and vertical steel. EN 1992-1-1 clause 9.6 sets minimum vertical reinforcement of 0.002 A_c (split between faces) and horizontal reinforcement of at least 25% of the vertical area or 0.001 A_c. Ø10–Ø12 at 200 mm each way is the common residential grid. This tool counts rows and bars, adds lap splices at 40 d_b, applies cutting waste, and converts to standard 6 m bar lengths. For isolated members use the concrete beam calculator or the concrete column calculator.
On pour day
Three things wall estimators forget. Minimum truck load — most ready-mix plants charge a small-load fee under ~3–4 m³, so a 6 m × 2.4 m × 20 cm single wall (≈3 m³) is right at the breakpoint where ready-mix beats bags. Formwork is the budget — concrete itself runs €100–130/m³ delivered in most EU markets in 2025, but forming, pouring, and stripping adds €25–50/m² of contact area; on a 2.4 m basement wall that's roughly €120–240 per linear metre before rebar. Mix class and exposure — basement and retaining walls in exposure XC2/XF1 need C25/30 minimum with air entrainment per EN 1992-1-1 Table 4.1, which adds ~€10/m³ vs. an interior C16/20 mix; agree the class with the supplier before the truck arrives, not after. Pump trucks (€500–900/day) are usually required when the chute can't reach the form. Curbs and stairs along the wall can be priced with the curb & gutter calculator and the concrete stairs calculator.
FAQ
How thick should a concrete wall be? Foundation walls: 20 cm minimum for single-storey; 25 cm for two-storey buildings; 30 cm for retaining walls over ~2.5 m retained height, per Eurocode 2 and local building codes.
How much concrete do I need for a basement wall? A 10 m × 6 m basement with 2.4 m high, 20 cm thick walls is ~32 m of perimeter × 2.4 m × 0.2 m ≈ 15.4 m³ before waste — about 16.9 m³ at 10% waste.
Does the calculator subtract openings? Yes. Enter the count and average opening size; the deducted volume is count × width × height × wall thickness, which also reduces the net formwork shown.
