Insulated concrete slabs are popular with some garden room designers. They offer extra headroom within the garden room which can be useful when designing a 2.5m high building.
A concrete slab is the traditional option for the foundation of a garden room. They take skill to get right and are made up from a series of layers.
Most garden rooms come complete with the foundation system included in the package, but a few dont and you will need to organise a concrete slab
Garden rooms need to be built on solid foundations, and there are many different types of foundation on offer such as concrete slabs and plinths and stilted foundations.