Arguably the most important among space allocation considerations is a functional analysis of the space. The functional use of the space can be graphically illustrated.

Typically, homes have four zones: social zones; work zones (kitchen, utility, office); private zones (bedrooms, bathrooms); and storage zones (cupboards, closets and cabinets). There are normally functional interrelationships between zones – certain zones have an adjacency relationship to one another – a kitchen is traditionally sited close to the dining area and bedrooms are typically grouped around a shared bathroom. Other zones may overlap – the kitchen-diner or ‘great room’ is an increasingly popular feature of modern homes. The space-planning process recognises which areas and functions are to be interrelated; that is to say, in a well-designed space, activities should flow smoothly and effectively from one zoned area into another.