Foam glass aggregate for building projects

It replaces heavy soil with a much lighter fill, so the ground below carries less added load. In Kelowna, the design sub-excavates 1.8 m and rebuilds with 1.2 m of foam glass aggregate and mineral aggregate above, for expected settlement under 25 mm over 50 years.^[1]

It adds thermal resistance under the slab^[4], but Enviro-Rock has not published a code evaluation for it. Moisture in service raises the conductivity of foam glass aggregate^[6], so the energy designer sets the design value, and the authority having jurisdiction decides what it accepts for a loose fill.

In confined testing by modified EN 1097-11, Enviro-Rock reaches 0.56 MPa at 10% deformation, 1.01 MPa (147 psi) at 20% and 1.67 MPa at 30%.^[5][10] These are index values for comparing aggregates, not allowable bearing pressures; the geotechnical engineer sets bearing values for the project.

Water absorption is 7.2% uncompacted.^[5] Closed cells inside each particle limit water penetration, while the spaces between particles drain freely.^[11]

Foam glass aggregate is buoyant, so specifications place it above the water table or hold it down with cover material.^[3] Where water can reach the fill, the design provides ballast or anchoring, as at Jim Lorimer Park in Burnaby.^[12]

In trailer loads from about 45 m³ up to 140 m³, or in 1.7 m³ super sacks.^[13] Enviro-Rock has been delivered from the Fraser Valley stockpile to downtown Vancouver.^[14]