Free Volume, Cost & Site-Mix Calculator – Updated 2026 Ready-Mix Prices
The price of C30/37 concrete per cubic metre in the UK in 2026 ranges from approximately £112 to £155 per m³ for ready-mix delivered by truck, depending on location, order volume, supplier, and any admixtures specified. In most of England, the average ready-mix price for C30/37 sits around £115–£138/m³ (ex-VAT) for standard delivery of 4 m³ or more. Greater London commands the highest prices — typically 15–20% above the South East base — while Northern England, Scotland, Wales, and Northern Ireland are generally 8–15% below. C30/37 typically costs approximately £8–£15/m³ more than C25/30 from the same supplier, reflecting its higher cement content and lower water:cement ratio.
C30/37 concrete — also referred to as RC30 or Grade 37 under older UK designations — provides a characteristic cube strength of 37 N/mm² at 28 days. It sits above C25/30 in the concrete grade hierarchy and below the heavy-duty C32/40 grade, making it the standard specification for structural concrete elements in domestic and light commercial buildings where loads or exposure conditions exceed what C25/30 can reliably handle. In 2026, C30/37 is widely specified for reinforced suspended slabs, structural columns and beams, retaining wall panels, pile caps, heavily loaded ground-bearing slabs, and any concrete exposed to moderate chemical or frost attack.
Our C30/37 concrete price per cubic metre calculator UK 2026 allows you to calculate the volume required for any pour, estimate the ready-mix order volume (rounded to the nearest 0.25 m³), and calculate either the ready-mix delivery cost, the site-mix material quantities for an RC30-equivalent mix, or the number of 20kg pre-mixed bags — all reflecting current 2026 pricing from major UK ready-mix suppliers including Hanson, Breedon, Aggregate Industries, and CEMEX.
The C30/37 designation follows the European concrete classification in BS EN 206: "C" for concrete, "30" for the characteristic cylinder strength in N/mm², and "37" for the characteristic cube strength in N/mm² — both at 28 days. In UK practice, the cube strength of 37 N/mm² is the more commonly referenced figure. C30/37 is broadly equivalent to the RC30 prescriptive mix under BS 8500-2, and to the old Grade 37 under the superseded BS 5328 standard. It is produced by certified ready-mix batching plants to a designed mix formulation, with conformance to BS EN 206:2013+A2:2021 confirmed on the delivery ticket for every load.
The key difference between C30/37 and C25/30 lies in the mix design: C30/37 requires a higher cement content (minimum 280–320 kg/m³ depending on exposure class) and a lower maximum water:cement ratio (0.55 for XC1 down to 0.45 for XD/XS/XF classes), producing a denser, less permeable concrete with significantly better durability in aggressive environments. This makes C30/37 the appropriate choice for applications where the concrete will be exposed to frost and de-icing salts, carbonation in external environments, chloride ingress in coastal or highway structures, or chemical attack from ground sulphates.
C30/37 is specified across a broad range of structural and demanding domestic applications in the UK. Its most common uses in 2026 include:
Several factors influence the ready-mix C30/37 price per m³ quoted by UK suppliers in 2026:
Get live C30/37 ready-mix quotes 2026: Hanson Ready-Mix UK | Breedon Group UK | Aggregate Industries UK | CEMEX UK Ready-Mix
For very small pours where ready-mix delivery is impractical, C30/37 can be approximated on site using the RC30 prescriptive mix: 1 part cement : 1 part sharp sand : 2 parts 20mm gravel by volume, or approximately 3 parts all-in ballast to 1 part cement by volume. Per cubic metre of finished concrete this requires approximately 480 kg of OPC cement (about 19 × 25kg bags), 1,500 kg of all-in ballast, and approximately 215 litres of water (water:cement ratio of approximately 0.45). This is a very stiff mix that is extremely difficult to hand-mix — a power mixer is essential. For any structural application, ready-mix with a certified delivery ticket is strongly preferred over site-mixing for C30/37.
The table below shows typical C30/37 ready-mix concrete prices per cubic metre across UK regions in 2026, for standard delivery on weekdays, no admixtures, and orders of 4 m³ or more. All prices are exclusive of VAT.
| Region | Low (£/m³) | Mid (£/m³) | High (£/m³) | Notes |
|---|---|---|---|---|
| North East England | £104 | £115 | £128 | Lowest prices in England |
| North West England | £106 | £117 | £130 | Manchester area slightly higher within region |
| Yorkshire & Humber | £106 | £117 | £130 | Competitive market with multiple plant operators |
| East Midlands | £108 | £120 | £134 | Good batching plant coverage |
| West Midlands | £109 | £121 | £135 | Birmingham area commands a premium |
| East of England | £112 | £124 | £140 | Rural areas incur delivery surcharges |
| South West England | £112 | £125 | £142 | Remote Devon/Cornwall can be significantly higher |
| South East England (excl. London) | £115 | £128 | £145 | Base reference region for this table |
| Greater London (Outer) | £128 | £142 | £160 | Higher labour, logistics, and ULEZ/LEZ compliance costs |
| Greater London (Inner) | £136 | £152 | £172 | Restricted access, congestion, ULEZ; highest prices in UK |
| Scotland | £106 | £118 | £134 | Edinburgh and Glasgow higher than national average |
| Wales | £104 | £116 | £132 | Rural Wales delivery surcharges apply |
| Northern Ireland | £100 | £112 | £126 | Lowest average ready-mix prices in the UK |
All prices exclude VAT, short-load surcharges (add £50–£150 for under 4 m³), admixture charges, pump hire, and Saturday/out-of-hours premiums. Always obtain at least two or three live quotes from local ready-mix suppliers before ordering — prices vary between plants even in the same area.
The table below places C30/37 in context with the full range of standard concrete grades used in UK construction, with equivalent designations, typical applications, and current 2026 ready-mix pricing for South East England.
| Grade (BS EN 206) | Cube Strength | BS 8500 Equiv. | Old Grade (BS 5328) | Typical UK Application | SE England £/m³ 2026 |
|---|---|---|---|---|---|
| C8/10 | 10 N/mm² | GEN 1 | Grade 10 | Blinding, non-structural fill | £85–£108 |
| C16/20 | 20 N/mm² | GEN 3 | Grade 20 | Light foundations, paths | £92–£115 |
| C20/25 | 25 N/mm² | GEN 3 / ST3 | Grade 25 | Domestic foundations, basic slabs | £100–£128 |
| C25/30 | 30 N/mm² | RC25 / ST4 | Grade 30 | Reinforced slabs, driveways, garage floors | £108–£136 |
| C30/37 | 37 N/mm² | RC30 | Grade 37 | Suspended slabs, columns, retaining walls, structural RC | £115–£145 |
| C32/40 | 40 N/mm² | RC32 | Grade 40 | Industrial floors, HGV hardstandings, concrete roads | £120–£152 |
| C35/45 | 45 N/mm² | RC35 | Grade 45 | Heavily loaded structural, ports, airport aprons | £130–£165 |
| C40/50 | 50 N/mm² | RC40 | Grade 50 | High-rise, transfer slabs, specialist structural | £144–£182 |
| C45/55 | 55 N/mm² | — | — | Prestressed elements, high-performance structures | £158–£200 |
The full technical specification for C30/37 concrete under BS EN 206:2013+A2:2021 and BS 8500-1:2015+A2:2019 as applicable in the UK in 2026:
| Property | C30/37 Value | Notes |
|---|---|---|
| Characteristic cylinder strength (fck) | 30 N/mm² | At 28 days; 5th percentile |
| Characteristic cube strength (fck,cube) | 37 N/mm² | At 28 days; 150mm cubes; principal UK reference value |
| Mean cylinder strength (fcm) | 38 N/mm² | fck + 8 per EN 1992-1-1 |
| Design compressive strength (fcd) | ~17 N/mm² | fck / γc; γc = 1.5 per Eurocode 2 (persistent/transient) |
| Modulus of elasticity (Ecm) | ~32 GPa | Secant modulus at 28 days per EN 1992-1-1 Table 3.1 |
| Tensile strength (fctm) | ~2.90 N/mm² | Mean axial tensile strength; used in crack width calculations |
| Density (normal weight) | ~2,370 kg/m³ | Fresh concrete; varies slightly with aggregate type |
| Max free water:cement ratio | 0.55 (XC1–XC2) / 0.50 (XC3–XC4) / 0.45 (XD/XS/XF) | Per BS 8500 Table A.3 by exposure class |
| Min cement content | 280 kg/m³ (XC1) / 300 kg/m³ (XC2–XC4) / 320 kg/m³ (XD/XF) | Per BS 8500 Table A.3 |
| Max aggregate size (standard) | 20mm | Reduce to 10mm where bar spacing < 50mm |
| Slump class (typical structural) | S3 (100–150mm) or S4 (160–210mm) with plasticiser | S4 preferred for congested reinforcement |
| Exposure class suitability | XC1–XC4, XD1–XD3, XF1–XF2, XA1 (with appropriate w/c) | Verify with BS 8500 Table A.3 for specific applications |
| Equivalent prescriptive mix | RC30 (1:1:2 cement:sand:gravel) | Per BS 8500-2 |
| Standard | BS EN 206:2013+A2:2021 / BS 8500-1:2015+A2:2019 | Conformance confirmed on delivery ticket (DS/1) |
Concrete specification standards: BSI Group – BS EN 206 / BS 8500 | The Concrete Centre UK | Institution of Structural Engineers
The table below compares site-mixed RC30 material quantities and costs against ready-mix C30/37 delivery pricing in 2026. The stiff RC30 mix (1:1:2 ratio) demands a power mixer and careful water control — it is not suitable for hand-mixing and is only practical for pours under approximately 0.5 m³.
| Material / Method | Quantity per m³ | Unit Size | 2026 Unit Cost (ex-VAT) | Cost per m³ |
|---|---|---|---|---|
| OPC Cement (25kg bags) | ~480 kg (~19 bags) | 25kg bag | £8.50/bag | ~£162 |
| All-in Ballast (bulk bag ~850kg) | ~1,500 kg (~2 bulk bags) | Bulk bag (850kg) | £58/bag | ~£102 |
| Water | ~215 litres | — | Negligible | ~£0 |
| Total Site-Mix Materials Cost | — | — | — | ~£264/m³ |
| Ready-Mix C30/37 (SE England avg. delivered) | — | — | — | £115–£145/m³ |
| Bagged pre-mix C30 (20kg bags) | ~111 bags | 20kg bag | £5.20/bag | ~£577/m³ |
Ready-mix C30/37 is clearly the most economical and consistent option for any pour above approximately 0.5 m³. The site-mix materials cost alone (£264/m³) is nearly double the ready-mix price, and that figure excludes the significant labour cost of mixing. Bagged pre-mix is even more expensive and is only justifiable for very small repairs or isolated post holes where the convenience outweighs cost.
The table below provides specification guidance for the most common UK structural and demanding domestic applications of C30/37 concrete, including minimum depths, reinforcement, and suitability notes.
| Application | C30/37 Suitable? | Min Depth | Reinforcement | Notes |
|---|---|---|---|---|
| Reinforced suspended floor slab (domestic) | Yes ✓ | 175–200mm | A252 / A393 + SE design | Structural engineer mandatory; preferred over C25/30 |
| Structural column (RC frame, domestic/light commercial) | Yes ✓ | As designed | Loose bar; links; SE design | Standard minimum for RC columns per most SE specifications |
| Pile cap / ground beam | Yes ✓ | As engineered | SE-designed bar arrangement | Common spec for piled foundations; higher cover required |
| Retaining wall panel (cantilever) | Yes ✓ | 200–400mm | SE-designed; two-layer mesh or bar | Geotechnical engineer and SE both required |
| Basement wall and floor slab | Yes ✓ | 250–350mm wall; 300–500mm slab | SE-designed, two-layer | Specify waterproofing admixture or WR grade; BS 8102 |
| External slab (frost-exposed, XF1) | Yes ✓ (with AEA) | 150mm | A193 or A252 | Specify air-entraining admixture for XF1 exposure class |
| Heavily loaded commercial ground-bearing slab | Yes ✓ | 150–175mm | A252 or A393 | Light FLT loading; heavier loading requires C32/40 |
| Agricultural yard / feed passage | Yes ✓ | 150mm | A252 | Specify sulphate-resisting cement if aggressive slurry present |
| Precast structural stair / landing | Yes ✓ | As designed | SE-designed loose bar | Standard precast structural spec; factory QA preferred |
| Standard domestic driveway (cars) | Yes (C25/30 adequate) | 125–150mm | A142 or A193 | C30/37 gives extra durability; marginal cost increase |
| HGV hardstanding / road pavement | Marginal ⚠ | 200–250mm | A393 | C32/40 preferred for regular HGV loading |
| Blinding / non-structural fill | Overspecified | 50–75mm | None | Use C8/10 or C16/20 – cheaper and adequate |
Ready-mix C30/37 costs approximately £115–£145/m³ (ex-VAT) in South East England in 2026. Northern England and Northern Ireland average £104–£128/m³; inner London up to £136–£172/m³.
C30/37 has a characteristic cube strength of 37 N/mm² at 28 days — 23% stronger than C25/30 (30 N/mm²) and the standard grade for structural reinforced concrete elements in UK domestic and light commercial buildings.
C30/37 typically costs £8–£15/m³ more than C25/30 from the same supplier. On a 5 m³ structural slab pour, that is only £40–£75 additional — a marginal cost for the improvement in structural performance and durability.
The RC30 prescriptive mix (1:1:2 cement:sand:gravel) requires approximately 480 kg cement and 1,500 kg all-in ballast per m³. This stiff mix demands a power mixer and is only practical for pours under ~0.5 m³.
Orders below the minimum load (typically 4–6 m³) attract a surcharge of £50–£150. For structural pours under 2 m³, the effective cost per m³ can double once the surcharge is included.
Replacing 30–50% of OPC with GGBS or PFA in C30/37 reduces cost by £5–£12/m³, lowers early heat of hydration (useful for thick sections), and improves long-term durability — a common structural specification in the UK.
Normal-weight C30/37 concrete weighs approximately 2,370 kg/m³ (2.37 t/m³). A full 8 m³ truck load weighs approximately 19 tonnes of concrete plus 15–22 tonnes tare weight = up to 41 tonnes gross.
Always retain the delivery ticket (DS/1) for every C30/37 load. It confirms grade, batch reference, BS EN 206 conformance, and volume. Building control officers and structural engineers require these for the project file.
Structural pours into tight formwork (columns, retaining walls, basement slabs) typically require a concrete pump. Pump hire costs £300–£700/day depending on pump size — budget this separately.
C30/37 is not inherently frost-resistant for fully exposed external applications. For XF1–XF2 exposure, specify air-entrained C30/37 (PAV1/PAV2 under BS 8500) with a target air content of 3.5–5.5%.
C30/37 achieves approximately 70–75% of its 28-day strength at 7 days. Do not remove formwork from structural members (columns, beams, suspended slabs) until adequate strength has been confirmed — typically 7–14 days minimum.
Ready-mix concrete is subject to VAT at 20% for most applications. New build residential construction is zero-rated — the contractor does not charge VAT on concrete for qualifying new dwellings.
Structural concrete elements using C30/37 are governed by the Building Regulations 2010 (as amended) and the relevant Eurocodes and British Standards. Because C30/37 is predominantly used for structural applications, regulatory compliance requirements are more demanding than for basic domestic GEN 3 / C20/25 work.
Any structural element constructed in C30/37 concrete — including suspended slabs, columns, pile caps, retaining walls, and basement slabs — requires a formal structural design to Eurocode 2 (BS EN 1992-1-1) by a suitably qualified structural engineer. The structural engineer's design will specify concrete grade, cover to reinforcement, lap lengths, joint locations, formwork striking times, and construction sequence. Building Control must be notified before structural concrete is placed, and an inspection at each key stage (foundations, reinforcement fixing, concrete placement) is required. Delivery tickets confirming C30/37 conformance with BS EN 206 / BS 8500 must be retained for the health and safety file.
For below-ground C30/37 elements (basement slabs, retaining wall bases, pile caps), Approved Document C requires protection against ground moisture and potentially against ground gases and contaminants. A DPM must be incorporated in ground-bearing elements of heated buildings. For basement structures, a formal waterproofing system to BS 8102:2022 must be specified by a specialist waterproofing engineer, independent of the concrete grade used. The higher density and lower permeability of C30/37 compared to C25/30 contributes to the water resistance of the concrete itself, but does not substitute for a properly designed waterproofing system.
Regulatory resources: GOV.UK Approved Documents A & C | IStructE | NHBC Standards 2026 | The Concrete Centre UK | CIRIA Publications
Ready-mix C30/37 concrete costs approximately £115–£145 per m³ (ex-VAT) in South East England in 2026, with the mid-market price around £128/m³. Regional variation is significant: Northern Ireland and North East England average £100–£128/m³, while inner London typically reaches £136–£172/m³. These prices assume standard weekday delivery of 4 m³ or more with no admixtures. For smaller orders, add a short-load surcharge of £50–£150. Plasticiser costs an additional £3–£8/m³; air-entraining admixture £4–£10/m³; waterproofing admixture £15–£35/m³. Always request at least two or three live quotes from local plants before ordering.
C30/37 is the standard structural concrete grade for reinforced concrete elements in UK domestic and light commercial buildings. Its principal applications are reinforced suspended floor slabs, RC columns and beams, pile caps and ground beams, retaining wall panels, basement walls and slabs, and external hardstandings requiring frost resistance. It is also used for precast structural elements (staircases, landing slabs, wall panels) and for agricultural hardstandings where C25/30 is insufficient for the specified loading or durability requirements. It is not normally specified for non-structural domestic applications where C20/25 or C25/30 is adequate and less expensive.
C30/37 has a characteristic cube strength of 37 N/mm² versus 30 N/mm² for C25/30 — approximately 23% stronger. C30/37 also requires a higher minimum cement content (280–320 kg/m³ depending on exposure class versus 260–300 kg/m³ for C25/30) and a lower maximum water:cement ratio (0.55 versus 0.65 for XC1 exposure), producing a denser and less permeable concrete matrix that provides superior durability in aggressive environments. C30/37 is appropriate when structural calculations require greater strength, or when the exposure class demands a more durable concrete. The ready-mix price premium is typically only £8–£15/m³, making the upgrade very cost-effective for structural applications.
Yes — virtually always. C30/37 is used predominantly for structural elements — suspended slabs, columns, pile caps, retaining walls, basement structures — all of which require formal structural design to Eurocode 2 by a suitably qualified and indemnified structural engineer. The structural engineer will specify the concrete grade, reinforcement arrangement, cover requirements, lap lengths, formwork striking criteria, and any special curing requirements. Attempting to construct structural concrete without a structural engineer's design carries a serious risk of structural failure, particularly for suspended slabs and retaining structures where the consequences of under-design are potentially life-threatening.
The site-mix equivalent of C30/37 is the RC30 prescriptive mix: 1 part cement : 1 part sharp sand : 2 parts 20mm gravel by volume, or approximately 3 parts all-in ballast to 1 part cement. Per cubic metre, this requires approximately 480 kg cement (19 × 25kg bags), 1,500 kg all-in ballast, and 215 litres of water at a water:cement ratio of 0.45. This is a very stiff, difficult mix that cannot be hand-mixed — a power mixer is essential. The total materials cost of approximately £264/m³ makes site-mixing considerably more expensive than ready-mix (£115–£145/m³), and the quality is less consistent. Site-mixing RC30 is only justified for pours under 0.5 m³ where ready-mix is impractical.
C30/37 without air entrainment is not fully frost-resistant for external applications exposed to repeated freeze/thaw cycles and de-icing salts (XF1–XF4 exposure). For frost-exposed external slabs, paths, and hardstandings in the UK, specify air-entrained C30/37 with a target air content of 3.5–5.5%, or use the PAV1 or PAV2 designations under BS 8500 for pavement concrete. The air-entraining admixture adds £4–£10/m³ to the ready-mix price. Air-entrained concrete should not be power-floated to a smooth finish as this reduces the air content at the surface — a brushed or exposed aggregate finish is more appropriate for external frost-exposed slabs.
Formwork striking times for C30/37 depend on the structural element, concrete temperature, and strength development. As a general guide at 15–20°C: vertical formwork to walls and columns can be struck after 12–24 hours once the concrete has hardened sufficiently to resist damage; soffit formwork to beams and slabs should not be struck until the concrete has achieved at least 70% of its characteristic cylinder strength — typically 7 days at 20°C, longer at lower temperatures. For critical structural elements, strength testing using cube test results or maturity-based methods (COMA-meter or wireless sensor logging) should be used to confirm adequate strength before striking. Never strike formwork based solely on elapsed time — always confirm with your structural engineer.
Yes — Ground Granulated Blast Furnace Slag (GGBS) and Pulverised Fuel Ash (PFA) are widely used as partial cement replacements in C30/37 structural concrete in the UK. GGBS is typically used at 30–50% replacement of OPC; PFA at 25–35%. Benefits include: lower heat of hydration (reducing thermal cracking risk in large pours), improved long-term durability and sulphate resistance, and reduced cost (GGBS and PFA are cheaper than OPC). The trade-off is slower early strength gain, which must be accounted for in formwork striking decisions and cold-weather working. GGBS and PFA concrete require longer curing periods than pure OPC mixes. Specify GGBS or PFA replacement level when ordering and confirm the mix design achieves C30/37 at 28 days.
When ordering C30/37 ready-mix, provide the following information to your supplier: concrete designation C30/37; maximum aggregate size (typically 20mm); slump class (S3 for standard structural work, S4 with plasticiser for congested reinforcement); any admixtures required (plasticiser, air-entraining agent, waterproofer, retarder); cement type if GGBS or PFA blend is specified; volume required in m³ (rounded to nearest 0.25 m³ including wastage); delivery address and required access route; preferred delivery date and time; and confirmation that BS EN 206 / BS 8500 conformance certificates will be provided with each load. Retain every delivery ticket (DS/1) received — building control and structural engineers require these documents for the project file.
Concrete cover to reinforcement in C30/37 structures is specified in accordance with Eurocode 2 (BS EN 1992-1-1) and BS 8500. The required nominal cover depends on the exposure class of the element. Typical values are: 35mm nominal for internal elements (XC1 exposure, dry environment); 40mm nominal for elements exposed to external weather or ground contact (XC3–XC4 exposure); 45–50mm nominal for elements in aggressive environments such as ground sulphates, coastal chloride exposure, or de-icing salt splash (XD/XS/XF classes). The nominal cover includes a tolerance of 10mm over the minimum cover. Cover must be maintained using correctly specified and positioned bar spacers and chairs — inadequate cover is one of the most common causes of reinforcement corrosion and structural durability failure.
Normal-weight C30/37 concrete has a density of approximately 2,370 kg per cubic metre (2.37 tonnes/m³). This is used in structural dead load calculations and for assessing delivery vehicle access. A standard 6 m³ ready-mix truck load of C30/37 weighs approximately 14.2 tonnes of concrete plus the truck's tare weight of 15–22 tonnes — giving a gross vehicle weight of approximately 30–36 tonnes. Ensure your site access road and any bridges on the delivery route can safely support this weight before booking a concrete delivery. If access is tight, request a smaller 4 m³ drum truck, or arrange for a concrete pump to reach the pour location from a safe standing position for the truck.
For a suspended floor slab measuring 8m × 6m × 0.2m (200mm deep): volume = 8 × 6 × 0.2 = 9.6 m³. Adding 10% wastage gives 10.56 m³ — round up to 10.75 m³ to order. At approximately £128/m³ (SE England mid-price), the concrete cost would be approximately £1,376 ex-VAT — a full load, so no short-load surcharge applies. If a concrete pump is needed to reach the slab formwork, add pump hire at approximately £350–£500/day. Always have your structural engineer confirm the slab depth and grade before ordering — suspended slab design is highly specific to the span, loading, and reinforcement arrangement and should never be estimated from generic benchmarks alone.
Additional Resources 2026: Ready-mix at Hanson UK | Breedon Group | Aggregate Industries | CEMEX UK | Structural guidance at The Concrete Centre | Find a structural engineer at IStructE | Regs at GOV.UK