Kitchen Unit Installation: Levelling Legs, Wall Cabinet Fixings into Masonry and Stud, Cornice, Pelmet and Kick Board Fitting

Quick Answer: Kitchen base units are levelled using adjustable legs (typically 100–150mm range) set to achieve a 870–900mm worktop height, then clipped together with cabinet connectors and secured to the wall. Wall cabinets are fixed to masonry with 7.5×75mm or 8×80mm frame screws at a minimum of 2 fixings per cabinet into a solid back rail or direct to the cabinet back; into timber stud, 4.5×50mm screws into studs at 400/600mm centres. Cornice, pelmet and kick board are finished to conceal gaps and complete the installation.

Summary

Kitchen unit installation is one of the most common and most technically varied jobs a general builder or carpenter undertakes. The difference between a professional result and a poor one is almost entirely in the preparation: surveying the floor level accurately before ordering, understanding the wall construction before selecting fixings, and taking time to achieve a truly level run of base units before any worktops are cut.

A poorly levelled kitchen will cause worktop joins to be uneven, appliance doors to not close properly, and integrated appliance gaps to be incorrect. These are expensive callbacks. Getting the setting-out right at the start — including accounting for out-of-square rooms, stud wall positions, and floor undulation — is the professional approach.

The British Standard for kitchen furniture installation is BS 6222 (domestic kitchen equipment), which covers worktop height, clearances, and structural requirements for wall cabinet fixing. Kitchen manufacturers also publish installation guides that must be followed to maintain warranty. Where the two conflict, the more stringent requirement applies.

Key Facts

Quick Reference Table

Spending too long on quotes? squote turns a 2-minute voice recording into a professional quote.

Try squote free →
Component Standard Dimension Adjustment Range Fix To
Base unit leg height 100mm nominal ±25mm per leg Self-contained
Worktop height 870–900mm FFL Shimmed via legs —
Plinth/kick board height 150mm Adjusts with legs Kick clips on legs
Wall unit bottom 1,370mm FFL Client preference ±50mm Wall
Wall unit top 2,050–2,150mm FFL Cabinet height Wall
Cornice 40–80mm profile Cut to fit Top of unit
Pelmet 50–80mm profile Cut to fit Underside of wall unit
Cabinet connector 5×30mm or 6×40mm N/A Adjacent cabinets

Detailed Guidance

Setting Out — Floor Survey and Reference Line

Before installing a single unit, survey the floor with a spirit level (minimum 1.2m) or laser level across the full width of the kitchen.

  1. Find the highest point in the floor. This is your datum for the front leg height.
  2. Measure the difference in level across the run — any undulation more than 20mm will require leg adjustment and may require shimming or cutting at the end panels.
  3. Strike a level horizontal line at worktop height (typically 870mm) on the walls. Use a laser or water level — a 3m tape and spirit level is not accurate enough.
  4. Check the room is square. Measure diagonals and strike a 90° line from the most prominent wall. Note any out-of-square for unit setting-out.

For an L-shaped or U-shaped kitchen, the corner unit is the datum: set it level and plumb first, then work away in both directions.

Installing Base Units

Step 1: Set and clip legs

Step 2: Connect cabinets

Step 3: Secure to wall

Wall Cabinet Installation

Wall cabinets carry significant weight — a fully loaded wall cabinet can weigh 25–40kg. The fixing must be into structural material.

Masonry (solid brick/block):

Plasterboard on stud wall:

Hollow concrete block or thermalite aerated block:

Fitting Cornice, Pelmet and Kick Board

Cornice:

Pelmet:

Kick board / plinth:

Frequently Asked Questions

The walls are badly out of plumb — should I pack the wall cabinets away from the wall?

Yes. If the wall leans more than 10mm over the cabinet height, pack with spacers at the top so the cabinets hang plumb and the doors open freely. Use flat plastic packers or cabinet-depth scribing strips. The gap at the wall can be concealed with a scribing strip or silicone if less than 15mm. For gaps over 15mm, fit a scribing panel — a full-height panel trimmed to follow the wall profile.

How do I handle a corner base unit — Lazy Susan or L-shaped?

For Lazy Susan (carousel) corners: the corner unit is always installed first; it must be level in all directions. Align the adjacent base units to the corner unit front face. The door overlay of the corner unit typically determines the setback of the adjacent unit face — follow the manufacturer's template.

For L-shaped false corner units: install the corner unit with 40mm clearance from the adjacent unit's door path. The gap is concealed by a false door/filler strip.

Can I fix wall cabinets into a chimney breast?

Only with extreme caution. Old chimney breast masonry may be:

Probe drill holes before fixing. If there is insufficient solid material, fix a 47×100mm timber batten horizontally, spanning solid masonry on each side of the chimney breast, and hang the cabinet from the batten.

What height for wall cabinets above a hob?

Approved Document J (combustion) and the hob manufacturer's installation guide specify minimum clearances above a hob. Typically:

Regulations & Standards