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Decca Tanks

GRP Housings, Cabinets & Walk-In Enclosures

Standard & bespoke equipment housings

Equipment protection
that fits your site.

Decca supplies GRP (glass reinforced plastic) housings for pumps, controls and site equipment. Choose a standard cabinet, a walk-in enclosure or a bespoke size.

Request an enclosure quotationShop housings

UK-made enclosures, with help on sizing, access and accessories.

Representative green GRP apex-roof walk-in enclosures with equipment access doors
Representative range images. The selected model, finish and accessories form part of your quotation.

Four product families

GRP cabinets and walk-in enclosures

Compare the four standard ranges below. Choose a cabinet for compact equipment or a walk-in enclosure for more space. If your layout needs a different size, we can help with a bespoke enclosure.

Bespoke sizes available

A bespoke housing for your space

Need a size outside the standard range? Send your available width, depth and height, plus an equipment layout. Decca will help you plan the enclosure, door access, ventilation and service entries.

Discuss a bespoke enclosure

Construction & finish

Weather-resistant GRP construction

Hand-laid GRP provides a weather-resistant finish and a low-maintenance enclosure body. Reinforcement, mounting points and openings are matched to the selected model and your equipment.

Support from brief to delivery

Our team helps with enclosure selection, drawing review and accessory choices. We agree the dimensions, finish, delivery and any installation work with you before the order is finalised.

GRP body
Polyester resin and E-glass with a UV-stabilised external gelcoat.
Colours
Standard green BS 4800 14C39 or grey 10A07. Alternative RAL and BS 5252 finishes can be requested.
Doors & fittings
Neoprene door seals and 304 stainless-steel fittings, with hardware matched to the chosen model.
Mounting
Integral bolt-down flanges; internal backboards available to suit the model.
Supply format
Fully assembled, or sectional where the enclosure size and site access require it.

Plan your space

Compare standard enclosure sizes

Open a range to compare width × depth × height in millimetres. Use these dimensions to shortlist a model. Decca can then check the clear internal space and door opening against your equipment.

S series — single-door cabinets
ModelWidth × depth × height (mm)
S1500 × 350 × 650
S2670 × 340 × 930
S3935 × 460 × 1140
S5750 × 400 × 1250

Single-skin models. Door and lock arrangements vary by model.

D series — double-door cabinets
ModelWidth × depth × height (mm)
D21190 × 600 × 1190
D31510 × 615 × 1470
D41750 × 745 × 1685
D52010 × 845 × 1685
D61200 × 500 × 2000
D71200 × 1000 × 2000

Single-skin models. Double doors provide wider access to the equipment space.

W1–W4 — flat-roof walk-in enclosures
ModelWidth × depth × height (mm)
W1 / W1A2000 × 500 × 2000
W2 / W2A2000 × 1000 × 2000
W3 / W3A2000 × 1500 × 2000
W4 / W4A2000 × 2000 × 2000

Single-skin and 12 mm plywood-core variants are listed in the range. We will confirm the required build in the quotation.

W5–W28 — apex-roof walk-in enclosures
ModelWidth × depth × height (mm)
W5 / W5A2500 × 2000 × 2500
W6 / W6A2500 × 2500 × 2500
W7 / W7A3000 × 3000 × 2500
W8 / W8A2500 × 1500 × 2500
W9 / W9A2500 × 3000 × 2500
W10 / W10A3000 × 1500 × 2500
W11 / W11A3000 × 2000 × 2500
W12 / W12A3000 × 2500 × 2500
W13 / W13A3500 × 1500 × 2500
W14 / W14A3500 × 2000 × 2500
W15 / W15A3500 × 2500 × 2500
W16 / W16A3500 × 3000 × 2500
W17 / W17A3500 × 3500 × 2500
W18 / W18A3500 × 4000 × 2500
W19 / W19A4000 × 1500 × 2500
W20 / W20A4000 × 2000 × 2500
W21 / W21A4000 × 2500 × 2500
W22 / W22A4000 × 3000 × 2500
W23 / W23A4000 × 3500 × 2500
W24 / W24A4000 × 4000 × 2500
W25 / W25A2500 × 3500 × 2500
W26 / W26A2500 × 4000 × 2500
W27 / W27A3000 × 3500 × 2500
W28 / W28A3000 × 4000 × 2500

Nominal height is 2500 mm across the listed apex range. Core, door and accessory arrangements are confirmed for the selected configuration.

Need another size? Explore bespoke enclosure sizes. Final dimensions, construction, door handing and accessory positions are confirmed on the approved drawing.

Configure your enclosure

Enclosure options and accessories

Choose the access, ventilation and fit-out your equipment needs. Decca can help review the options against your layout.

Doors, locks & mounting

  • Single or double doors, with agreed handing and outward swing.
  • Door stays and alternative locks, including three-point locking on suitable models.
  • Plywood backboards for mounting equipment.

Ventilation & service entries

  • Louvres and high- or low-level ventilation.
  • Cable access and gland entries.
  • Lifting eyes and opening positions agreed on the drawing.

Panel cores & floors

  • Plywood-core or insulated panels.
  • 25, 50 or 75 mm insulation, subject to the build.
  • Normally open-bottomed, with an optional integrated GRP-encapsulated floor.

Optional electrical packages

  • Lighting, distribution, heating and frost control.
  • Loose components or an agreed pre-mounted package.

Electrical fit-out is optional. Site connection and certification are by a qualified electrician unless included in the quotation.

Base & access

Plan the base and installation access

Provide a flat, level and suitably designed concrete slab or plinth, with a fixing arrangement matched to the enclosure and site.

Start with at least 500 mm working clearance, then allow for the full outward door swing and the equipment manufacturer’s service access. Decca can review the layout with you.

Need a particular performance level?

Tell us about any fire, ingress, thermal or acoustic requirement when you enquire. Performance depends on the complete enclosure, including doors, vents, service entries and panels.

We will review the proposed build and confirm what supporting evidence is available.

  1. Share your brief

    Send equipment dimensions, a layout or drawing, site conditions and required access.

  2. Agree the specification

    We review the standard or bespoke size, openings, options and supply scope with you.

  3. Confirm & supply

    Approve the quotation and drawings, then agree delivery and any installation arrangements.

Technical literature

Brochures and technical specifications

Compare models in the product brochure, or check construction and installation details in the general specification.

Questions about GRP housings

What is a GRP housing?

A GRP housing is an equipment enclosure made from glass reinforced plastic. It provides a weather-resistant space for pumps, controls or other site equipment. Cabinets suit compact equipment; walk-in enclosures provide more internal space.

Can you supply bespoke enclosure sizes?

Yes. Send your available width, depth and height, plus an equipment layout or drawing. Decca will review a bespoke size and the access, ventilation and accessories it needs.

Are floors and electrics included?

Housings are normally open-bottomed. Integrated floors and electrical packages are optional. The quotation and order identify the supplied equipment and any site work.

Can the doors and openings be changed?

Door handing, locking, ventilation, cable access and other modifications can be reviewed for the chosen model. Send a marked-up layout so we can check positions and practical access before manufacture.

Can you provide a fire-rated or IP-rated enclosure?

Tell us your fire or ingress protection (IP) requirement when you enquire. Any quoted rating must cover the complete enclosure, including doors, vents and cable entries, with supporting evidence. Fire-retardant resin alone does not establish a certified fire rating for the whole enclosure.

Talk to Decca

Request a GRP enclosure quotation

Send a model number, dimensions or equipment drawing. Our team will help you choose the enclosure and confirm the supply scope.

  • Standard model or bespoke width, depth and height
  • Door access, ventilation and cable-entry positions
  • Location, finish and any performance requirement
  • Floor, electrical fit-out and delivery requirements
Send an enclosure enquiryBrowse shop housings

Need water storage and equipment space together? Explore combination units in the shop.

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