PerLite Construction-Grade exfoliated perlite is used as a versatile aggregate in plaster, floor screeds and roof screeds for slopes-to-fall and concrete. It offers excellent lightweight, thermal insulation, sound dampening and fire-protection properties. Perlite is chemically inert, non-combustible, odourless and durable, PH-neutral and has a very low carbon footprint. Perlite i s a non-toxic, naturally occurring siliceous volcanic rock. Perlite is formed by the rapid cooling of viscous magma or lava.