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Phase 1: Garage Kitchen Budget Estimate

This document provides a rough cost estimate for converting half of a standard garage into an EHO-compliant prep kitchen. This budget assumes a 3m x 3m (9m²) working space. It includes various options depending on your budget and how much DIY you are comfortable with.

Note: Prices are estimates (in GBP £) and can vary wildly depending on how much DIY you are willing to do versus hiring tradespeople.

1. Structural & Room Prep

Assuming you need to partition a 3m x 3m section of the garage, insulate, and make it weatherproof.

ItemDIY EstimateTradesperson EstimateNotes
Stud Wall Partition & Insulation£300£800 - £1,200Timber, Celotex/Kingspan, plasterboard (for a 3m partition wall + lining existing walls).
Subtotal£300£800 - £1,200

2. EHO-Compliant Surfaces (Walls & Ceilings)

Environmental Health requires all surfaces to be smooth, impervious, and easy to clean. Here are two main approaches for a 3x3m space (approx 36m² of wall/ceiling surface).

Option A: Plaster & Hygienic Paint (Professional Finish Only)While materials are cheaper, achieving a smooth, EHO-compliant finish with plaster is not a DIY job. You must hire a pro to skim the walls.

ItemDIY EstimateTradesperson EstimateNotes
Plastering / SkimmingN/A£400 - £700Skimming plasterboard smooth (Pro only).
Hygienic/Epoxy Wall Paint£100£200 - £300Washable, anti-bacterial paint (can be painted yourself).
Option A Subtotal£100 (Paint only)£600 - £1,000

Option B: PVC Hygiene Cladding (More Expensive / Easier DIY)More expensive materials, but much easier to DIY a perfect finish by gluing directly to raw plasterboard.

ItemDIY EstimateTradesperson EstimateNotes
Wall & Ceiling Cladding£500 - £750£1,000 - £1,500~14-16 standard 2.5mm PVC sheets + trims + adhesive.
Option B Subtotal£500 - £750£1,000 - £1,500

Flooring (Required for both options)

ItemDIY EstimateTradesperson EstimateNotes
Vinyl or Epoxy Flooring (9m²)£200£400 - £700Non-slip commercial vinyl (like Altro) or painted epoxy floor paint.

3. Plumbing & Water Supply

Bypassing the cost of trenching the driveway by using a self-contained mobile-style system vs running mains water.

Option A: The Water Tank Route (Budget / Self-Contained)Avoids driveway trenching. Easy DIY.

ItemEstimated Cost (DIY)Notes
2x 25L-50L Water Tanks (Fresh & Waste)£60 - £100Jerry can style or larger baffled tanks.
12v/240v On-Demand Water Pump£60 - £150e.g., Seaflo or Flojet system.
Under-sink Electric Water Heater£100 - £150e.g., Ariston 10L (plugs into a standard socket).
Hoses, connectors, waste traps£50 - £80Standard plumbing fittings.
Option A Subtotal£270 - £480Cannot easily be done by trade as it's a mobile setup.

Option B: Mains Plumbing & Waste (Premium / Tradesperson recommended)Connecting to the house mains (approx 20m away). Requires trenching driveway/garden.

ItemDIY EstimateTradesperson EstimateNotes
Trenching (20m) & Making Good£200 (Hire mini-digger/wacker)£1,000 - £2,000Digging 20m channel, laying pipes, refilling/repairing surface.
Mains Water & Waste Pipework£150£500 - £800MDPE water pipe and 110mm soil pipe.
Macerator Pump (If uphill to sewer)£300£400 - £600e.g., Saniflo if waste needs to be pumped up to existing drains.
Internal Plumbing & Hot Water Heater£200£400 - £600Connecting sinks, installing local water heater.
Option B Subtotal£850£2,300 - £4,000

4. Kitchen Equipment & Fit-Out

Look for second-hand commercial stainless steel (Nisbets clearance or eBay) to save money.

ItemEstimated CostNotes
Commercial Oven (Electric)£400 - £800Standard 13-amp plug-in convection oven (e.g., Lincat/Blue Seal). Keeps electrical costs down.
Countertop Induction Hob£50 - £150Much easier for EHO sign-off than gas. Portable 13-amp units are cheap and effective.
Extractor Hood (Above Hob)£100 - £250High-power domestic hood. EHO will allow this since prep is restricted to light cooking/sauces (no heavy grease/frying). Must be vented externally.
Stainless Steel Double Sink£150 - £300Essential for washing equipment separately from food prep.
Handwash Basin (Knee-operated)£80 - £150EHOs love knee-operated or sensor taps for hygiene.
Stainless Steel Prep Tables (x2)£150 - £300Must be stainless steel, not wood.
General Room Extractor Fan£50 - £150Core drilled through the wall to reduce ambient humidity.
Subtotal£980 - £2,100

5. Electricals (Lighting & New Circuits)

For a 3x3m kitchen running multiple heating elements (oven, water heater) and heavy appliances, a dedicated supply is crucial. You will need a qualified electrician to sign this off, even if you run the cables.

ItemDIY EstimateTradesperson EstimateNotes
IP65 Lighting & Ample Sockets£100 - £150£200 - £3502x LED waterproof battens (plenty for 9m²), 4-6 double sockets, conduit/cabling.
Dedicated Circuit / Sub-board£150 (Materials)£400 - £800To manage multiple high-draw appliances safely (Oven, Water Heater, Fridges).
Electrical Spec Check / Upgrade£50 - £150£300 - £600Garage has power, but an electrician must confirm if the existing feed can handle the load or if an upgraded cable from the house is needed.
Electrician Final Connections & Sign-offN/A£300 - £600Mandatory professional requirement.
Subtotal£300 - £450£1,200 - £2,350Assumes you buy materials/run cables (DIY) vs them doing all labour.

What to DIY vs What to Hire a Pro For

To get the best balance of cost-savings and professional finish, here is the recommended approach:

🟢 Easily DIY'd (High Cost Savings)

  • Stud Walls & Insulation: Very forgiving work. Mistakes are hidden behind cladding.
  • PVC Hygiene Cladding (Option B): Gluing sheets to the wall is straightforward and much easier than learning to plaster.
  • Equipment Installation: Assembling stainless tables, positioning the oven, mounting the sinks.
  • Water Tank System (Option A): Just basic hoses and 12v/plug-in electrics. Very low risk.
  • Cable & Conduit Routing: You can physically run the electrical cables and mount the surface conduit yourself to save the electrician's time, leaving the final connections to them.

🟡 DIY With Caution (Moderate Skill Required)

  • Trenching for Mains Water (Option B): Hiring a mini-digger is cheap, but hitting existing services (gas/electric) or improperly laying the 110mm waste pipe with the wrong fall/gradient can be disastrous.
  • Epoxy Floor Painting: Needs meticulous concrete cleaning and prep, otherwise it peels quickly.
  • Core Drilling for Extractor: Renting a core drill is easy, but drilling through double-brick requires care.

🔴 Hire a Professional (Safety / Compliance / Skill)

  • Electrical Final Connections & Sign-off: Mandatory. Do not wire the sub-board or connect to the mains yourself. It must be certified.
  • Plastering (Option A): Plastering is an art form. If it's lumpy, the EHO won't like it because it's hard to clean. Hire a pro if you want painted plaster walls.
  • Mains Plumbing Connections (Option B): Ensuring watertight, compliant connections to the main sewer lines.

Estimated Totals (Examples)

  • The "Bootstrapper" (Max DIY, Tank Water, PVC Cladding): ~£2,700 - £4,330
  • The "Hybrid" (DIY Prep, Pro Plaster & Sparky, Mains Water Trenching by you): ~£3,980 - £6,450
  • The "Turnkey Pro" (Trades do everything, Mains Water, PVC Cladding): ~£7,450 - £11,950+

Next Steps

  1. Check Electrical Spec: Have an electrician (or knowledgeable person) check the breaker size feeding the garage. A standard 13-amp oven + water heater + fridges running simultaneously could trip a basic domestic spur.
  2. Floor Plan Sketch: Map out a rough 3x3m floor plan to ensure sinks, oven, and tables fit efficiently without crossing clean/dirty prep areas.