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Vertical Garden / Living Wall Calculator

Size a living wall or green facade: choose a system, check the saturated structural load, get planting density, automated irrigation sizing, an itemised bill of materials, an indicative budget and a multi-year cost of ownership.

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Inputs

Horizontal span of the wall to be greened.

Vertical height of the planted area.

Drives planting density, weight, water demand and cost.

Indoor walls need supplementary grow-lighting and recirculating irrigation.

Drives plant choice and outdoor water demand.

8 advanced inputs hidden. Switch to Advanced to fine-tune.

Confidencelow· 45Complexitylow· 10

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Wall area (m²)
10
Plants needed
300
Saturated load (kg/m²)
75m²
Total saturated load (kg)
750kg
Water demand (L/day)
15
Indicative total (£)
5,568
Indicative cost (£/m²)
557m²
Living wall specification — Modular hydroponic panels

10 m² exterior wall (4 × 2.5 m). All figures are indicative UK trade benchmarks — confirm against a structural survey and supplier quotes.

Plants

300

30 plants/m²

Saturated load

75

kg/m²

Water

15

L/day

Indicative

£557

per m²

Saturated load ≈ 75 kg/m² (750 kg total). Commission a structural survey of the host wall and fixing design before proceeding.

Automated irrigation is essential for this system — hand-watering leads to plant failure and voids most supplier warranties.

Frost risk — winterise the irrigation (drain down / trace heating, Oct–Nov) and specify frost-hardy species only.

Structure

  • Saturated dead load75 kg/m²
  • Total saturated load750 kg
  • Growing medium150 L (3 × 50 L bags)
  • Modules / cassettes40

Irrigation

  • Daily water demand15 L/day
  • Peak (summer)24 L/day
  • Annual consumption≈ 3,750 L/yr
  • Reservoir tank100 L
  • Pump dutySmall submersible (~500 L/hr)
  • Drip line≈ 39 m

Bill of materials

  • Waterproof membrane (EPDM) · 10 m²£120
  • Ventilation battens (25–50 mm gap) · 10 m²£60
  • Cement particle backing board (12 mm, A2) · 10 m²£220
  • HDPE root barrier · 10 m²£40
  • Galvanised subframe rails (600 mm centres) · 10 m²£350
  • Planting modules / cassettes · 40 modules£1,680
  • Growing medium (50 L) · 3 bags£27
  • Plug plants (P9–P12) · 300 plants£1,200
  • Concealed drainage gutter · 4 m£112
  • Powder-coated edge trim · 13 m£117
  • Irrigation header + drip line · 39 m£47
  • Pump & digital controller · 1 set£320
  • Reservoir tank · 100 L£140
  • Fittings, valves & fertigation dosing · 1 set£180
  • Sealed chemical anchor fixings · 10 m²£80

Indicative budget

  • Materials£4,693
  • Labour (~25 hrs @ £35/hr)£875
  • Estimated install total£5,568

Indicative UK supply + labour; excludes access equipment, delivery and VAT. Refine against real quotes.

Cost of ownership

  • Maintenance visits4/year
  • Annual maintenance£450/yr
  • Plant replacement≈ 7% of plants/yr
  • Expected lifespan15+ years
  • Maintenance over 10 yrs£5,340

Why a living wall

A dense evergreen wall improves the host wall's U-value by up to ~25%, buffers heat and noise (~5–10 dB), filters PM2.5–PM10 and NO₂, intercepts rainfall to ease surface-water runoff (SuDS), and counts towards Biodiversity Net Gain and BREEAM ecology credits when maintained under contract.

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Essentials for this job

Quantities include a ~10% waste allowance. Guide prices are indicative UK ranges (materials only, inc. VAT) — always confirm with the supplier before ordering.

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This app provides general UK guidance and material estimates only. It is not legal, planning, engineering or building-control advice. Always confirm requirements with your local planning authority, building control, utility providers, manufacturers or qualified professionals.