Design - Sublime Insulating Limecrete Floor vs Slab and Screed

The conventional approach to a ground bearing slab is to use a structural slab of concrete as the base and then install insulation and a screed containing the underfloor heating above. We used to follow a similar pattern with a limecrete slab on top of the Glapor, followed by the underfloor heating pipework and an additional screed, but we have refined the system to be more efficient and cost effective. 

Using a single Limecrete slab has several benefits, using a 100mm slab incorporating the underfloor heating uses less material, requires less labour for mixing and laying the limecrete and reduces the overall drying time before the floor can be finished. Installing the pipework requires a little more care as the pipes / clip rails have to be installed on the geogrid rather than the solid slab surface, however this it not generally an issue. Occasionally customers are concerned the response time of the system may be slightly slower due to the pipework being lower in the floor structure, overall there is less mass for the pipework to heat up so while they are not as close to the surface the response time is very similar. 

There may still be instances where a slab and screed as desirable for scheduling reasons, for example if the floor of a building needs to be laid in several phases so the UFH pipework cannot be carried throughout. In these instances and initial slab can be installed as the phases progress and once ready for the UFH all of the pipework can be laid altogether and covered with a limecrete screed.