Perlite concrete aggregate combined with portland cement and water produces a lightweight insulating concrete used for lightweight roof decks, floor fills, lightweight structural decks, insulation for steam and coolant lines, bases of cryogenic storage tanks, oven insulation, interstitial spaces in reconditioned water and sewer lines, interstitial floors in hospitals, lightweight pre-cast forms and blocks, statuary, basic fills, and many other applications where a lightweight permanent concrete is desired.
Although many uses could be described in greater detail, the most common and well-established use has been for insulating flat roof decks.
Physical properties of perlite concrete vary according to mix designs. Perlite concrete can be made with a dry density of 320 kg/m3 or with the addition of sand or other aggregates up to 1440 kg/m3.
Perlite light weight insulating concrete applicationThe lower the density, the higher the insulating value.
For most uses to maintain a proper balance between insulation value and compressive strength, a 1:6 (one part Portland cement by volume to 6 parts perlite by volume) mix is chosen with a density between 384 and 480 kg/m3. This provides a k factor range of 0.085 to 0.095 W/m-k and a compressive strength of 125 to 200 psi (986 to 1378 Pa).