Briefing the Builder: How Restaurants Get Gas, Water and Drainage Right for New Kitchen Gear
Buying new kitchen equipment is the easy part. Getting it to actually work once it lands is where projects stall, budgets blow out and opening dates slip. The gap is rarely the gear itself — it is the brief. Builders, hydraulic consultants and licensed plumbers can only design and rough-in what they have been told, and if the gas load, water pressure or waste route for a new combi oven, fryer bank or dishwashing station is discovered after the slab is poured, someone is paying for it. A clear, written services brief given to the builder before setout is one of the cheapest risk controls available to any café, restaurant, pub, club, bakery or catering kitchen.
Build the Brief From the Equipment Schedule, Not the Floor Plan
Most projects start with a floor plan and a wish list. That is the wrong order. The brief should be built from an equipment schedule — a line-by-line list of every item going into the kitchen, from the range and chargrill through to refrigeration, servery, beverage gear and dishwashing — with the manufacturer’s specification sheet attached to each line. Spec sheets carry the numbers builders need: gas input in MJ/h or kW, inlet and outlet connection sizes, required water pressure and flow, waste outlet diameter and height, condensate requirements, flue type and clearance to combustibles, plus physical dimensions and weight.
From that schedule, create a simple services matrix that shows, for each item, what it needs and where. Four columns cover most of it: gas, cold water, hot water and drainage. Add notes for anything unusual — a pumped waste, a floor waste, a tempering valve, a water filter, a grease arrestor connection, a flue penetration through a wall or roof, or a condensate drain running to a tundish. Anything that leaves the building’s existing services needs to appear here, not in a conversation on site.
Timing matters as much as content. The brief needs to reach the builder and hydraulic consultant before pipe sizes, floor falls and slab penetrations are locked in. On a refurbishment, that means before demolition exposes what is actually there. On a new build, it means before the first rough-in inspection. Hand over the schedule, the spec sheets and a marked-up plan showing connection points, and nominate who is responsible for what: the builder for coordination, the plumber for water and waste, the gasfitter for gas, the equipment supplier for dimensions and delivery, and you for sign-off on the final layout. Ambiguity about responsibility is where most disputes begin.
Build in spare capacity too. Kitchens rarely stay as designed, and a brief that allows for an extra connection point or a slightly larger waste line is far cheaper than cutting into finished walls twelve months later.
Translate Specs Into Builder Language: Gas Loads, Water Quality and Waste Routes
Builders and plumbers do not think in menu items — they think in loads, sizes, gradients and clearances. Translating equipment specs into that language is where a good brief earns its keep.
Gas. Total up the MJ/h rating of every gas appliance at full fire, and note whether the design assumes diversity. A kitchen with six gas items rarely runs everything flat out at once, but the gasfitter still needs the figures to size the meter, pipework and regulator. Flag each appliance’s connection size, whether it needs a specific regulator, and where isolation valves should sit so a technician can service the unit without shutting down the line. If a new appliance needs a flue or a canopy hood above it, say so early — clearance to combustibles, hood overlap and interlock with the fire system all affect framing and services rough-in.
Water. Cold and hot supply needs are not interchangeable. A Commercial dishwasher may call for a hot supply at a specific temperature, a minimum pressure and flow rate, plus a dedicated trapped waste — while a combi oven or steamer may need filtered water to protect it from scale. Note each outlet’s required pressure in kPa, the flow rate, and whether a tempering valve, backflow prevention device or water treatment unit belongs on that line. Handwash basins and staff facilities need their own compliant supply, and those are frequently forgotten when the brief focuses only on cooking gear.
Drainage. Waste is the most common source of rework. Specify which items drain by gravity and which need a pump, what diameter each outlet is, how high off the floor it sits, and where the waste must run. Grease-bearing waste from sinks and pre-rinse stations typically needs to reach a grease arrestor sized for the load, and the local water authority may require a trade waste agreement before anything connects. Floor wastes, tundishes, condensate drains and rodding access all need a place in the plan, along with adequate fall. Get the waste route wrong and you will be looking at a raised plinth, a pump you did not budget for, or a floor that never quite drains.
Walk the Site, Confirm the Numbers and Lock It In Before Rough-In
Paper only gets you so far. The brief should be walked on site with the builder, plumber, gasfitter and — ideally — whoever is supplying the equipment, before rough-in begins. Tape the appliance footprints on the floor. Check that the setout dimensions match the actual equipment dimensions, not the catalogue sketch, and allow for door swings, drawer pull-outs, service access and the space needed to clean behind and beside each unit.
Use the walk to test the practical questions that drawings hide. Can the new range get through the door, around the corner and into position, or does a frame need to come out? Is the delivery path clear of steps, tight lifts and low clearances? Do floor levels and falls work with the equipment’s leg height and plinth? Where does the flue terminate, and does it clash with a neighbouring window or air intake? On an operating venue, can the work be staged so the kitchen keeps trading — and if so, which circuits, gas lines and drains need to stay live?
Get approvals sorted in parallel. Landlords and strata committees often need to see the services brief before approving penetrations, flue locations or trade waste connections, and shopping centre management may impose their own conditions on grease arrestors and grease trap access. Confirm who will issue the gas compliance certificate and the plumbing certificate of compliance, and make sure those documents, plus as-built drawings and commissioning records, land in your file before final payment.
Finally, agree the change process. Picture a site where the client swaps a single-tank dishwasher for a larger model after rough-in — suddenly the hot water demand, the waste size and the bench cut-out all move. A brief that states who approves changes, in writing, and how they flow to the trades prevents that small decision from becoming a three-week delay. Lock the numbers, record the sign-offs, and keep the schedule live as a working document rather than a file that gets archived the day the builder starts.
Born in Kochi, now roaming Dubai’s start-up scene, Hari is an ex-supply-chain analyst who writes with equal zest about blockchain logistics, Kerala folk percussion, and slow-carb cooking. He keeps a Rubik’s Cube on his desk for writer’s block and can recite every line from “The Office” (US) on demand.