With the intent to outline the minimum insulation requirements for suspended floors and concrete slabs on ground, J1.6 Floors introduces additional stringency in all climates and building classes.
In terms of minimum Total R-value (m².K/W) requirements, values equal to or greater than 2.0 and 3.25 are required for without in-slab heating/cooling and with in-slab heating/cooling), respectively. This includes a soil R-value factor, calculated as per Specification J1.6 or Section 3.5 of CIBSE Guide A.
If the floor has in-slab or in-screed heating or cooling system, except where used solely in a bathroom, amenity area or the like, it must be insulated around the vertical edge of its perimeter with insulation having an R-Value greater than or equal to 1.0.