The ground floor of a building has to achieve a variety of performance requirements, some of which may be more obvious than others. It often has a role to play in the thermal performance of the building fabric, and must also be capable of bearing the loads imposed by the use of the building.

The type of ground on which the floor is constructed also determines how the floor build-up should be specified to perform. The construction must prevent water from the ground getting inside the building, and may also need to resist the passage of radon gas. This is covered in a separate blog post “How do building regulations impact on ground floor design?”.

What are the structural requirements of a ground floor?

Most of us probably take for granted the ability to move around inside a building, but it requires the correct specification of a floor build-up to make sure we can do so safely and comfortably. The ground floor has to provide a sound, level base for the intended use of the building.

Beyond that, however, the floor can also lend structural stability to the building. Much depends on the type of floor construction, of course. A suspended floor is typically used on sites with unstable ground or excessive slopes.

While the ground floor helps with the transfer of load into the ground and the building’s foundation, it does not act as a foundation in its own right. The exception is a raft slab, which combines the floor slab and foundation in one. It is a shallow foundation that compensates for poor ground, and is best suited to low-rise buildings.

Specifying thermal insulation for ground floor performance requirements

Thermal insulation manufacturers, particularly those offering rigid foam boards, often like to promote their solutions on the basis of being the thinnest and most efficient. The range of performance requirements for a ground floor construction, however, demand different qualities from an insulation product used in the build-up.

It is like comparing athletes in different sports. Usain Bolt, for example, dominated headlines for being the fastest sprinter in the world. A champion in multi-event sports, such as the decathlon, has to be good at a wider range of disciplines. Their results in an individual discipline do not generate the same attention, but they are an impressive all-round performer.

Extruded polystyrene (XPS) insulation is like the multi-event champion, providing the qualities necessary to meet all of the requirements of a ground floor. Read our separate blog post on different types of ground floor insulation, or contact us to book our new CPD seminar on the benefits of XPS as floor insulation, and find out more about how Polyfoam XPS can help with your ground floor specifications.