Many of our insulating underlay have excellent thermal insulation values which when applicable we express this as a tog rating.
The higher the star rating on our thermal underlay the better the heat insulation properties of the underlay. E.g. 5 star very good, 1 star probably suitable for under floor heating, provided the product is described as "suitable to be used with under floor heating"
We appreciate that you may need further help and advice when choosing Thermal Underlay for Under Floor heating so please give our friendly and knowledgeable team a call...