Garden Patio Volume, Materials & Cost Calculator – Updated 2026 Prices
Enter your patio dimensions, intended use, and preferred supply method to calculate the concrete volume, materials list, and estimated cost for a concrete patio or garden hardstanding in the UK. The calculator covers rectangular patios, L-shaped patios, and circular features, and compares ready-mix, volumetric, and site-mixed (bagged) options so you can choose the best value method for your project.
A concrete patio is one of the most durable, low-maintenance, and cost-effective garden surface options available to UK homeowners in 2026. When correctly specified and installed, a concrete patio will last 25–40 years with minimal maintenance — significantly longer than block paving (which requires re-sanding and re-levelling every 5–10 years) or timber decking (which requires annual treatment and replacement every 15–25 years). Concrete patios are particularly suited to the UK climate where frost, rain, and heavy foot traffic demand a robust, impermeable surface.
The key decisions when planning a concrete patio are: the correct slab thickness for the intended use (100mm is the minimum for foot traffic; 150mm for vehicle use); the correct concrete mix specification (GEN 3 / C25 for basic domestic use; C30 or C30 air-entrained in Scotland and northern England where frost is a significant concern); the need for a sub-base (100mm of compacted MOT Type 1 hardcore is essential for a patio that stays level and does not crack due to ground movement); and the surface finish (a brushed or broom finish is the standard non-slip external finish for UK patios).
For most domestic UK patios of 6–20 m², the choice of concrete supply method comes down to: ready-mix drum truck (best for pours over 3 m³ — approximately 30 m² at 100mm depth — where good vehicle access is available); volumetric / mini-mix (best for 0.5–3 m³ — 5–30 m² at 100mm — especially where access is restricted); or bagged concrete mixed on site (only economical and practical under approximately 0.3 m³ / 3 m² of patio). This calculator automatically recommends the most economical option for your dimensions and provides a cost comparison.
The most common cause of patio concrete failure in the UK is not the concrete itself — it is the absence or inadequacy of the sub-base. Concrete is strong in compression but weak in tension. If the ground beneath the slab is soft, uneven, or susceptible to movement (frost heave, tree root activity, shrinkable clay shrinkage), the slab will crack and drop unevenly even if the concrete itself is properly specified. A correctly prepared sub-base distributes the load from the surface to the underlying soil and provides a stable, uniform bearing for the concrete.
For domestic patios in the UK, the standard sub-base is 100mm of compacted MOT Type 1 crushed limestone or granite (also called hardcore or DTp1/Type 1 sub-base). This must be spread in layers, compacted with a vibrating plate compactor, and brought to a level surface before the concrete is poured. For vehicle-trafficked areas, increase the sub-base to 150mm. On soft or made ground, 200mm or more may be required. Never pour a patio slab directly on uncompacted or loose topsoil — the slab will crack within months.
The table below gives estimated all-in costs (concrete + sub-base + labour + VAT) for concrete patios of common sizes at standard 100mm thickness in South East England in 2026. Deduct approximately 10% for North England, Midlands, Wales, and Scotland.
| Patio Size | Concrete Volume (m³) | Supply Method | Concrete Cost (excl. VAT) | All-In Cost (incl. sub-base, labour, VAT) | Cost per m² (all-in) |
|---|---|---|---|---|---|
| 3m × 2m (6 m²) | 0.66 m³ | Volumetric / mini-mix | £185–£260 | £650–£950 | £108–£158/m² |
| 4m × 3m (12 m²) | 1.32 m³ | Volumetric / mini-mix | £280–£380 | £1,100–£1,600 | £92–£133/m² |
| 5m × 4m (20 m²) | 2.20 m³ | Volumetric / mini-mix | £420–£550 | £1,600–£2,400 | £80–£120/m² |
| 6m × 4m (24 m²) | 2.64 m³ | Ready-mix or volumetric | £470–£620 | £1,850–£2,750 | £77–£115/m² |
| 6m × 5m (30 m²) | 3.30 m³ | Ready-mix (above minimum) | £530–£700 | £2,200–£3,200 | £73–£107/m² |
| 8m × 5m (40 m²) | 4.40 m³ | Ready-mix | £650–£860 | £2,800–£4,000 | £70–£100/m² |
| 10m × 5m (50 m²) | 5.50 m³ | Ready-mix | £790–£1,040 | £3,400–£4,900 | £68–£98/m² |
All-in costs include: concrete supply + delivery, 100mm MOT Type 1 sub-base, timber formwork, labour to pour and brush-finish, and 20% VAT. SE England 2026. Deduct ~10% for northern England and Scotland. Exposed aggregate and pattern-imprinted finishes add £15–£40/m² to the all-in cost. Reinforcement mesh (A142) adds approximately £5–£8/m². Costs assume level or near-level ground with reasonable vehicle access.
| Patio Surface Type | Typical Installed Cost (m², SE England, incl. VAT) | Expected Lifespan | Maintenance | Notes |
|---|---|---|---|---|
| Plain concrete (brushed finish) | £70–£120/m² | 25–40 years | Minimal (annual weed killer, pressure wash every 2–3 years) | Best whole-life value; most durable; can appear utilitarian without decorative finish |
| Pattern-imprinted / stamped concrete | £90–£160/m² | 20–35 years | Re-seal every 2–4 years | More decorative than plain; sealant adds ongoing cost; popular for driveways too |
| Block paving (clay or concrete blocks) | £85–£145/m² | 20–30 years | Re-sand and re-level every 5–10 years; weed treatment | Permeable options available (SuDS); reusable if lifted; settles unevenly over time |
| Natural stone (Indian sandstone / York stone) | £120–£250/m² | 30–50+ years | Annual sealing; occasional re-pointing; algae removal | Premium appearance; very long-lasting; higher initial cost; slippery when wet if unsealed |
| Porcelain paving | £100–£200/m² | 25–40 years | Low maintenance; easy to clean; needs anti-slip surface externally | Very popular in 2026; durable; slippery when wet if standard tile spec used |
| Timber decking (softwood) | £60–£110/m² | 10–20 years | Annual staining/treatment; periodic plank replacement; slippery when wet | Warmer underfoot; lower initial cost but higher maintenance; shorter lifespan |
| Composite decking | £110–£200/m² | 20–25 years | Low (annual wash); fade-resistant; more durable than timber | Higher upfront cost than timber; good modern aesthetic; not as long-lasting as concrete |
| Resin-bound gravel | £75–£130/m² | 15–25 years | Low; permeable; may need patch repairs | SuDS compliant (permeable); attractive appearance; requires solid concrete or tarmac base |
Patio concrete and garden landscaping resources UK 2026: Checkatrade – Find a Patio Installer | TrustATrader | Which? – Garden Paving Guide | RHS – Hard Landscaping | The Concrete Centre
| Item | Typical Cost (2026) | Notes |
|---|---|---|
| MOT Type 1 sub-base (per tonne, delivered) | £28–£45/tonne | 100mm depth at 2.0 t/m³ compacted density ≈ 0.2 m³/m² = ~0.37 tonnes/m²; 12 m² patio needs approximately 4.4 tonnes |
| Vibrating plate compactor (day hire) | £55–£90/day hire | Essential for compacting sub-base; DIY hire from HSS, Speedy, or local plant hire |
| Timber formwork (softwood boards, per metre) | £1.50–£3.50/m linear | 100mm × 38mm softwood boards around perimeter; reclaimed timber can be used |
| Formwork pegs / stakes | £0.20–£0.60 each | Every 600–900mm; knocked into ground to hold formwork; screwed or nailed to boards |
| DPM (damp-proof membrane, per m²) | £0.30–£0.80/m² | 1200-gauge polythene laid over sub-base before concrete; prevents rising damp; essential for covered patios or internal use |
| A142 mesh reinforcement (per m²) | £4–£8/m² | Optional for domestic patios; recommended for vehicle-trafficked areas; 200×200mm mesh, 6mm wire |
| Plastic spacer chairs (per pack of 50) | £5–£12 | Holds mesh 40–50mm off sub-base if reinforcement is used; prevents mesh sitting on ground |
| Expansion joint filler strips (per metre) | £1.50–£4.00/m | Bitumen-impregnated fibreboard; placed at slab edges and around obstacles; allows thermal movement |
| Angle grinder / diamond blade (joint cutting) | £20–£40/day hire | For saw-cut contraction joints; cut at least 25mm deep within 6–12 hours of pour; prevents random cracking |
| Concrete sealer (per litre) | £8–£25/litre (covers 8–15 m²) | Applied after 28-day curing; improves stain and frost resistance; optional but recommended for exposed patios |
| Skip hire (excavated material) | £220–£450 per skip | For excavated topsoil; 1 m³ removed = approximately 1.5 tonnes; check local permit requirements for roadside skip |
| Excavation labour (per m²) | £8–£18/m² | Hand or machine excavation to formation level (typically 250–300mm below finished surface level including sub-base and slab) |
The minimum practical thickness for a concrete patio used on foot is 100mm. Thinner slabs (75mm or less) are prone to cracking under normal domestic use — garden furniture, wheelbarrows, and occasional vehicle crossing all generate point loads and edge stresses that a thin slab cannot resist. For vehicle-trafficked areas, increase to 150mm minimum. It is a very common and expensive mistake to pour a thin slab to save on concrete costs — the marginal cost of an extra 25mm of thickness is small compared to the cost of breaking up and re-laying a failed slab.
GEN 3 / C25 (characteristic cube strength ~30 N/mm²) is adequate for domestic patio slabs on foot traffic only. For patios in the UK that may experience freeze-thaw cycles — particularly in northern England, Wales, Scotland, and elevated locations — C30 with air entrainment (XF1 or XF2 exposure class) provides significantly better frost resistance. The premium is typically only £8–£15/m³, making it excellent value for the durability improvement. Any patio adjacent to a road or drive that receives de-icing salt splash should be specified to C30 XF2 as a minimum.
Many concrete patio failures in the UK are caused by inadequate or absent sub-base preparation. Without a compacted sub-base, the concrete slab has no uniform bearing — soft spots in the topsoil cause differential settlement, and frost heave in winter lifts and cracks the slab from below. Always excavate to the correct depth (typically 250–300mm below finished patio level), install at least 100mm of compacted MOT Type 1 hardcore, and bring to a level surface before pouring concrete. This costs approximately £8–£14/m² but adds many years to the slab life.
Concrete shrinks as it cures and expands and contracts with temperature changes. Without contraction joints, this movement causes random, unsightly cracking across the slab surface. Contraction joints are formed by saw-cutting or tooling a groove at least 25mm deep (approximately one-quarter of the slab depth) at maximum 4m centres in both directions, within 6–12 hours of placing the concrete. The joint creates a weak line where the concrete preferentially cracks — invisible within the joint. For a 4m × 3m patio, one central joint in the long direction is usually sufficient.
A brushed or broom finish is the correct surface finish for an external patio slab. The light texture provides adequate slip resistance when wet — important for a UK climate where the patio will be wet for much of the year. A smooth or steel-trowelled finish is suitable for internal floors and covered areas but becomes extremely slippery when wet if used externally. Apply the brush finish at right angles to the direction of normal foot travel (i.e. across the slope), and while the surface is still soft enough to take the texture but firm enough not to smear.
In England, a concrete patio within the curtilage of a house generally does not require planning permission under Permitted Development rights, provided the total area of hard surfacing within the curtilage does not exceed 5 m² of impermeable surface (or uses permeable paving / provides drainage to a soakaway for larger areas). This change was introduced in 2008 to manage surface water runoff. Front garden patios and driveways exceeding 5 m² of impermeable surface require planning permission or must be drained to a soakaway or SuDS feature. Always check with your local planning authority if in doubt.
Concrete bases for hot tubs, swim spas, garden rooms, summer houses, and large sheds require more careful specification than standard patio slabs. Hot tubs typically weigh 2,000–5,000 kg when filled — comparable to a small car on the footprint of a large sofa. Specify a minimum of 150mm thick, C30 reinforced slab (A142 mesh) on 150mm compacted sub-base for hot tub bases. Garden room bases should also be reinforced and typically 125–150mm thick. Always confirm the loading with the garden room manufacturer and your structural engineer for heavy structures.
Freshly poured patio concrete must be kept moist for at least 3–5 days to allow proper hydration and achieve its design strength. In warm or windy weather, cover the slab with polythene sheeting immediately after the surface finish is applied — this traps moisture and prevents premature drying that causes surface dusting, cracking, and reduced surface strength. In cold weather (below 5°C), cover with insulating blankets to prevent frost damage. Do not walk on the slab for at least 24–48 hours and avoid placing heavy loads until 7 days. Full 28-day strength develops over the following weeks.
Comparing whole-life costs, concrete patios are typically 15–30% cheaper than block paving over a 25-year period. Block paving has a higher initial installation cost (more labour-intensive), requires re-sanding and re-levelling every 5–10 years (typically £12–£25/m² per treatment), and individual blocks can sink, crack, or heave. Plain concrete, by contrast, requires only periodic pressure washing and weed treatment, and a well-laid slab should need no significant maintenance for 20–30 years. The main advantage of block paving is its repairability — individual blocks can be replaced — and its aesthetic variety.
Pattern-imprinted (stamped) concrete — where the fresh slab is pressed with textured mats to create the appearance of stone, brick, or slate — is increasingly popular for UK garden patios and driveways. It costs approximately £90–£160/m² installed, compared to £70–£120/m² for plain brushed concrete. The imprinting must be done while the concrete is still plastic, typically 3–8 hours after pouring depending on weather and mix. A release agent (coloured powder) prevents the mats from sticking and provides a contrasting colour to the base colour. The surface requires sealing every 2–4 years to maintain the colour and surface protection.
All external concrete patios should be laid with a minimum 1:60 fall (approximately 17mm per metre) away from the house to prevent water collecting against the building or standing on the surface. For a 3m-wide patio, this means the outer edge is approximately 50mm lower than the edge against the house wall. The fall must be consistent across the slab and should direct water to a garden, soakaway, or drain. Never direct patio runoff to a highway drain without permission. For patios against the house, ensure the finished patio level is at least 150mm below the damp-proof course (DPC) of the house wall to prevent water bridging.
Ready-mix concrete supply for a domestic patio is subject to 20% standard rate VAT. The labour element of a professional patio installation is also VAT-rated at 20%. There is no VAT relief for domestic patio or garden works. However, for new residential dwellings (new build or conversion to residential), the supply of concrete and associated labour is zero-rated, which is a significant saving. For alterations to listed buildings, reduced rate (5%) VAT may apply in some circumstances. Always confirm the VAT position with your contractor — for large patio projects, the VAT element can be substantial.
The concrete volume for a patio is calculated as: area (m²) × thickness (metres). For example, a 4m × 3m patio (12 m²) at 100mm (0.1m) thickness requires 12 × 0.1 = 1.2 m³ of concrete. Always add a wastage allowance — typically 10% for a rectangular patio — giving an order quantity of 1.32 m³. At 100mm thickness, you need approximately 0.11 m³ per m² of patio area. Use this calculator to get the exact volume and volume-to-order for your specific dimensions and wastage allowance. For most small UK domestic patios (6–20 m²), the concrete volume will be 0.66–2.20 m³ — within the ideal range for volumetric (mini-mix) concrete.
For a domestic garden patio used only on foot (seating area, barbecue area, plant displays), 100mm is the standard and recommended minimum thickness. This provides adequate strength and durability for normal domestic use on a properly prepared 100mm compacted sub-base. For occasional vehicle crossing (e.g. a wheelbarrow or garden tractor), 100mm is still adequate. For regular car parking, increase to 150mm. For vans or heavy vehicles, use 200mm on 150mm sub-base. Thinner slabs (75mm) are only suitable for very lightly used paths and should not be used for sitting-out areas where garden furniture, BBQs, and plant pots will be placed.
For most UK domestic garden patios, GEN 4 / C28 (or C30 for better frost resistance) is the recommended mix. GEN 3 / C25 is technically adequate for foot-traffic-only areas but provides little margin for UK frost conditions. C30 — particularly C30 with air entrainment (XF1 class) — provides significantly better freeze-thaw resistance and is particularly recommended in northern England, Wales, Scotland, and anywhere with regular winter frost. In southern England where frost is mild, GEN 3 or GEN 4 is commonly used and performs well. For driveways or patios adjacent to roads where de-icing salt may be present, specify C30 XF2 (air-entrained with freeze-thaw + de-icing agent resistance).
The all-in installed cost of a concrete patio in the UK in 2026 ranges from approximately £70–£120 per m² (incl. VAT) for a plain brushed-finish slab, rising to £90–£160/m² for pattern-imprinted concrete. For a typical 12 m² (4m × 3m) patio, expect to pay approximately £1,100–£1,600 all-in including concrete, sub-base, formwork, labour, and VAT. For a larger 30 m² patio, the all-in cost is approximately £2,200–£3,200. These costs include the concrete supply, 100mm MOT Type 1 sub-base, excavation, formwork, and labour to pour and brush-finish. They exclude any decorative sealing, coloured concrete, or complex landscaping features. Always get at least three quotes from contractors.
In England, a rear garden patio does not require planning permission under Permitted Development rights in most cases. However, since 2008, impermeable hard surfacing in the front garden (including the side of a house if visible from the highway) requires either: keeping the total impermeable area under 5 m²; using permeable paving; or providing drainage to a soakaway. Rear garden patios are not subject to this restriction unless they exceed certain height thresholds near boundaries. In Conservation Areas or for listed buildings, additional restrictions may apply. In Wales, Northern Ireland, and Scotland, rules differ slightly. Always confirm with your local planning authority before starting work if in doubt.
For a small patio of under approximately 8–10 m² (0.8–1.0 m³ of concrete), the choice is between volumetric (mini-mix) concrete and bagged/site-mixed concrete. Bagged concrete (pre-mixed all-in-one bags) is cheapest per m³ only for very small volumes — under approximately 0.2–0.3 m³ (2–3 m² of patio). Above this, the labour cost of mixing bags and the risk of inconsistent mixing makes volumetric concrete far more practical and often cheaper in total. Volumetric (mini-mix) concrete delivers freshly mixed concrete to your site with no minimum order — you pay a call-out fee (typically £80–£160) plus a per-m³ rate — and is the best choice for most domestic UK patios. Drum ready-mix becomes economical only when volume exceeds approximately 3 m³ (30 m² at 100mm).
A concrete patio should not be walked on for at least 24–48 hours after pouring, and should not have heavy loads (furniture, BBQ, plant pots) placed on it for at least 7 days. Do not drive a car over a concrete patio slab for at least 14–21 days, and ideally wait the full 28-day curing period before any regular vehicle use. Concrete achieves approximately 70% of its 28-day strength at 7 days under normal UK conditions (15–20°C). In cold weather (below 10°C), strength gain is slower — allow additional time before loading. Keep the slab covered with polythene for the first 3–5 days to retain moisture and assist curing.
Concrete patio cracking has four main causes in UK domestic construction. Inadequate or absent sub-base: the most common cause — soft spots in the sub-grade cause differential settlement, and the slab cracks. Absence of contraction joints: concrete shrinks as it cures; without saw-cut or tooled contraction joints at maximum 4m centres, random cracking occurs across the surface. Slab too thin: a 75mm slab cannot resist normal garden loads without cracking; 100mm is the minimum. Premature loading: placing heavy loads on the slab before 7–14 days causes flexural cracking in the partially-cured concrete. If your patio has cracked significantly, repair options include epoxy injection for structural cracks, or re-laying sections with proper sub-base preparation and joint provision.
Yes — a concrete patio is one of the most achievable DIY projects for a competent home improver, particularly for a small patio (under 10 m²) where volumetric concrete can be ordered to pour in one go. The key steps are: excavate to the correct depth; compact 100mm of MOT Type 1 sub-base; construct timber formwork at the correct level with a fall of at least 1:60 away from the house; order volumetric concrete (easier for small pours than drum ready-mix); pour, screed, and brush finish the slab; cut or form contraction joints within a few hours; and keep covered and moist for 3–5 days. The main risks for DIYers are: insufficient sub-base compaction; incorrect levels and falls; working too slowly on large areas (concrete begins to stiffen within 90 minutes); and inadequate curing. For areas over 20 m² or where the specification is critical (vehicle use, extension base), professional installation is recommended.
Concrete patio sealing is optional but improves stain resistance, reduces frost damage, and enhances the surface appearance. Apply sealer after the concrete has cured for at least 28 days. Clean the surface thoroughly and ensure it is completely dry. For exterior patios, use a penetrating silane/siloxane sealer (soaks into the surface; not visible; best for plain brushed concrete) or an acrylic topcoat sealer (sits on the surface; gives a sheen; required for pattern-imprinted concrete). Apply with a roller or brush per manufacturer instructions. Re-apply every 2–4 years for acrylic sealers, or every 5–10 years for penetrating sealers. In the UK, a sealer is particularly beneficial for patios in Scotland and northern England where frost and de-icing salt are significant concerns.
Additional patio concrete resources UK 2026: Checkatrade – Find a Patio Installer | TrustATrader – Patio & Landscaping | RHS – Hard Landscaping | The Concrete Centre | Planning Portal – Permitted Development