Selecting the wrong design or size oven can result in a misfit and a return of product, possibly at a cost. Both single (one compartment) and double (two compartment) ovens can fit into both categories (built-in or built under), but each category has different installation features, size requirements, pricing and unit housing designs. Compartments are sometimes referred to as cavities.
The maximum height a built under oven can be manufactured to is 720mm (according to United Kingdom standards), because this is the same height as a standard kitchen base unit. Built-in ovens can be manufactured larger, to heights of 1200mm, because they can be part of a larder-style cupboard or unit.
Built under appliances are designed to sit on the kitchen floor, whereas built-in appliances are designed to fit fully in a specially-made housing. Built-in ovens can be raised to chest height for easy opening and closing and would be fully encased in a housing to support them and make them safe to use.
Because built under ovens are shorter than built-in ovens they provide less space inside each compartment. In the case of double ovens, one or both compartments will be smaller in terms of capacity. Built under ovens are typically 75 per cent the capacity of built-in ovens.
Because built-in ovens are hidden behind a unit and fascia; they are more discreet and stay cleaner in most cases.
A built-in oven is installed inside a specially prepared unit and is typically anything other than a free-standing appliance.
Because of the generally greater number of plus points of built-in ovens, they are more popular and more households purchase them than their built under counterparts. The majority of single compartment built-in ovens are electric. Only a small proportion are gas. The majority now have energy ratings.