Built-in appliances: what to measure first

Why the order matters

A built-in appliance is not a piece of furniture but an almost finished block with requirements of its own: its own niche width and height, its own clearance for heat, its own place for a socket, its own side for the cable or hose. A furniture maker does not invent these figures, they copy them out of the appliance data sheet into the carcase drawing.

That sets the whole sequence of work. First the owners choose the appliances, then the surveyor takes their dimensions, and only then does the board go to the saw. The reverse order costs more than any amount of haste: an oven housing built "to a standard" will not accept every oven, and a hob cut-out cannot be made smaller once it has been cut too large.

There is one honest exception. If the appliances are being bought later, the specification records exact niche dimensions rather than a model, and the owners then look for a unit that fits those figures. That works, but the choice of appliances is narrower, and it is better to know that in advance rather than in the shop.

What you need to know about each appliance

What matters is not the size of the box but the niche dimensions and the practical details nobody asks about in a showroom.

What to do before the survey

1. 1

   List the appliances

   Write down everything that will be built in: oven, hob, extractor, dishwasher, microwave, fridge, waste disposer. Even something you intend to buy later belongs on the list, because space is left for it.

2. 2

   Find the niche dimensions

   What is needed is the manual page with the niche drawing. For appliances already bought that is the data sheet in the box; for ones not yet bought, the model page in the shop where the installation diagram is shown. Photographs of those diagrams are entirely enough.

3. 3

   Check the services in the room

   Where the sockets, water, waste, gas and extraction duct currently are. An appliance has to sit so that neither cable nor hose runs behind the carcase; if a service is badly placed, it is moved before the furniture goes in, not after.

4. 4

   Give the figures to the surveyor

   The surveyor transfers the niches into the drawing and shows what goes where. At this stage a model can still be changed; once the board is cut, it cannot.

5. 5

   Look for the niches in the specification

   Before signing, make sure the niche and cut-out dimensions appear in the document as figures, not as the phrase "for the client's own appliances". That way the figures are part of the agreement rather than somebody's memory.

Where it goes wrong most often

The first and commonest mistake is treating "60 centimetres" as a single dimension. Appliances 60 cm wide take niches from 56 to 60 cm and vary in depth, and ovens of the same width differ in niche height. That is exactly why the model data sheet goes into the drawing rather than a round number heard in passing.

The second is a socket behind the appliance. It is put where it suits the electrician, and then the appliance will not go the last two centimetres into its niche, or the plug cannot be reached. Socket positions are agreed together with the furniture drawing, in one pass.

The third is an extractor chosen at the very end. The extractor sets the height of the wall unit above the hob and where the duct will run; added to a finished design, the duct starts running across door fronts. So the extractor is discussed alongside the hob, not separately.

The fourth is an appliance bought by eye for a kitchen that already exists, which happens when something breaks mid-renovation. Then the order is reversed and that is the only correct way round: measure the niche you already have and look for a model that fits it.