The basic Utilihab flooring structure is a Secondary frame profile grid of long 50mm thick joists 100-200mm deep depending on span and 50-100mm spacers. They are arrayed in a grid 1025mm on center, creating 1m square spaces. The basic drop panel form is a 20-25cm thick panel in some composite of materials. In some cases the floor grid may employ slot-less edge profiles for the sake of a finished look with simplified construction -assuming no later changes to intermediate partitions. This is particularly suited to smaller structures. But in most cases conventional profiles are used and are covered either by cosmetic finishing strips, the edges of fitted panel, a continuous floor surface, or carpeting.
Many floor panels will be equipped with fittings for electrical and communications outlets and have junction boxes attached to their undersides. They may also integrate HVAC vents and up-lighting fixtures and may even be employed whole as a lighting element using a resilient translucent panel material -as we will discuss in detail in the Lighting section.
Certain floor coverings -in particular tatami flooring which is based on special woven mats- require the floor grid to be sunken relative to the edge of the Primary framing. With the exception of very small structures, this may be limited to buildings using the Medium and Heavy framing.