Kitchen Unit Installation - Excluding Appliances

The fitter handles the carpentry side of the kitchen. The goal is a kitchen that stands level and solid, with every door and drawer opening and closing properly. The work usually includes:

• Assembling the unit carcasses according to the manufacturer's plan
• Setting and levelling the base units on their adjustable legs
• Hanging the wall units and fixing them securely to the wall
• Joining the units together into one solid run
• Measuring, cutting and fitting the worktop, including cut-outs for the sink and hob
• Fitting plinths, cover trims, end panels and wall trims
• Adjusting hinges, doors and drawers

Some work is left out: connecting the oven, hob, dishwasher and cooker hood, fitting the sink and tap, connecting water and waste, moving sockets, new wiring and under-cabinet lighting. Electrical connections must be done by a qualified electrician. If the kitchen has gas, only a qualified, registered gas engineer may connect or disconnect a gas cooker or hob. If you ever smell gas, turn off the supply at the valve, open the windows, do not touch light switches and call the gas emergency line or 112.

An experienced fitter starts by checking the room. They measure it, check how flat the walls and floor are and compare everything with the kitchen design. They find the highest point of the floor, because the height of the whole kitchen is set from there. Only then do they mark a level line on the wall for the base units and for the hanging rail of the wall units.

Why start with the base units? They form the foundation for the worktop, and the whole line of the kitchen is checked against them. The units are set up, levelled in both directions with a spirit level and screwed together. Then come the wall units. Their height depends on the cooker hood and on who will be cooking in the kitchen. The gap between the worktop and the wall units is usually around 50 to 60 cm.

Next comes the worktop. It needs careful cutting, because walls rarely meet at a perfect right angle. Cut-outs for the sink and hob follow the template or the dimensions from the appliance manufacturer. On better worktops, corner joints are made with a machined joint and worktop connector bolts. This joint is almost invisible and resists moisture better than a simple butt joint with a trim. Finally, the plinths, trims and panels go on, and every door and drawer is adjusted.

A kitchen is one of the last things to go in. Before the fitter arrives, these should be finished:

• The final floor, so the kitchen does not have to be lifted or taken apart later
• Plastering and painting, plus tiling if it runs behind the units
• Water, waste, electrical points and the hood extraction outlet, in the right places according to the kitchen design

The services do not need to be connected, but their positions must be clear. Otherwise a socket can end up behind the side of a unit, or a waste pipe directly under a partition. Clear the room and the route from the front door. A long worktop needs space to be moved around, and the units need somewhere to be unpacked and checked for damage before installation begins.

The condition of the room matters most. In a new build with straight walls and a new floor, installation goes smoothly. In older flats and period houses, walls are often out of plumb and floors uneven. The fitter then has to level out bigger differences, adjust trims and scribe the worktop to follow a crooked wall. All of that takes longer.

The size and shape of the kitchen also play a part. A straight run is simpler than an L-shaped or U-shaped kitchen with corner units, tall larder units or an island. The worktop material matters too:

• Laminate is the usual choice, is cut on site and its cut edges must be sealed
• Solid wood needs room to move naturally and has to be treated with oil
• Stone and quartz composite are usually measured once the units are in place, and the supplier makes the cut-outs

The wall itself can complicate things. Brick and concrete take standard wall plugs, aerated concrete blocks need special fixings, and plasterboard needs cavity fixings or, ideally, timber or metal reinforcement built into the partition.

In practice, a kitchen often looks fine on installation day and the problems appear a few months later. The usual causes are:

• Units not levelled properly, so doors swing open on their own and drawers rub
• Wall units hung on unsuitable fixings that slowly work loose
• Unsealed cut edges on a laminate worktop near the sink, which then swell
• A worktop fixed tight against the wall, which warps or cracks as humidity changes
• A kitchen fitted before the floor or tiling is finished, which then has to be taken apart

The simplest protection is to stick to the right order of work and not to skimp on fixings.

A handy DIYer with a spirit level, a drill and a helper can assemble and fit a simple straight kitchen. Leave electrics, water and gas to the professionals. Never hang wall units on your own, always work in pairs.

1. Check the delivery against the parts list and unpack the units.
2. Find the highest point of the floor and mark a level line for the base units from there.
3. Use a detector to find cables and pipes in the wall.
4. Assemble the carcasses following the manufacturer's instructions, without doors for now.
5. Set up the base units, level them with the legs and screw them together.
6. Fix the hanging rail with fixings suitable for your type of wall.
7. Hang the wall units with a helper and tighten the hanging brackets.
8. Measure and cut the worktop, then seal the cut edges.
9. Fix the worktop to the units from below and fit the wall trim.
10. Fit the doors, drawers and plinths and adjust everything.

At handover, walk through the kitchen calmly with a spirit level in your hand. Check that:

• The worktop is level along its length and from front to back
• The gaps between doors are even and the doors line up
• Doors stay put in any position and do not swing open by themselves
• Drawers run smoothly and close fully
• Wall units do not move when you pull on them
• Worktop joints are smooth and cut edges are sealed
• The sink and hob cut-outs match the appliance dimensions
• Water and electrical points can be reached through openings in the units
• Plinths and trims fit properly and nothing is scratched