UK Standard

BS 8500 — Concrete Specification

BS 8500 — Concrete. Complementary British Standard to BS EN 206

In short: BS 8500 is the UK national standard for concrete specification and production, governing the strength grades (such as C20, C25, C30) and durability mixes used for foundations and slabs.

What BS 8500 covers

It translates the European concrete standard (BS EN 206) for UK use, defining structural strength and durability requirements for exposure to moisture, freeze-thaw, and chemical ground conditions.

Standard domestic grades include C20 (general slab, patio base), C25 (standard foundations/strip footings), and C30 (reinforced driveways under vehicle load).

The standard specifies maximum water-to-cement ratios, minimum cement contents, and permitted cement replacements like GGBS (ground slag) to reduce carbon emissions.

Common BS 8500 domestic concrete grades
Grade Compressive strength Best domestic use
C20 20 N/mm² General slabs, patio bases, shed bases
C25 25 N/mm² Foundations, trench footings, retaining walls
C30 30 N/mm² Driveways, highly trafficked / reinforced slabs

Apply this standard

Calculators that use BS 8500

Concrete Volume Calculator
Slabs, footings, columns and steps. Ready-mix vs bagged, reinforcement mesh, embodied carbon and adjustable waste.
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Official source: BSI Knowledge — BS 8500 series. Figures on this page are a plain-English summary for estimating purposes — always refer to the published standard for compliance.