Compaction Guide

Glavel as a sub slab aggregate layer derives much of its load bearing strength and thermal insulation from compaction. A foam glass install’s compaction is done at a 1.3 : 1 ratio, which locks the frictional pieces to one another, creating a smooth layer upon which slab can be poured. 

The compacting of Glavel takes place with a light vibratory plate. A support layer for the foundation slab is achieved with the devices listed below. The type of vibrating plate to be used depends on the properties of the sub grade and the Glavel layer thickness. It is highly recommended that a test area is used at a suitable location to check the compaction behavior of the layer sequence.

For hard surfaces and low gravel layer thicknesses, lightweight devices tend to be suitable. For softer surfaces and large insulation Glavel layer thicknesses, heavier devices are required.

The compression ratio of the insulation ballast layer is 1.3 : 1. The compaction is to be stopped when the target value is reached. Any additional compaction will serve only to increase material consumption without increasing insulative value or compressive strength. 

A compacted Glavel layer of Glavel can be flattened to + – 1 inch over a 6 square yard area.

Notice for compaction with rollers:
Compaction of the insulation ballast with rollers of all types is not recommended, because in this compression method, the grain rearrangement is not done correctly and the bearing capacity of the insulation ballast layer can be impaired. 

The video below shows a Glavel layer compaction. Notice how stable and level the layer is after a round of compaction. For more information about Glavel compaction or technical specs, schedule a time to speak with our associates here.

Determining the base area (Ap)
The base area is the area on which Glavel foam glass gravel must be installed on. Please consider the vertical protrusion above the ground slab.

Determining the delivery quantity (L)
The necessary quantity results out of the product of base are, finished installation height, and compaction ratio.

L = Ap • Hv • v
L = Quantity delivered (m3)
Ap = Base area (m2)
Hs = Dumping height (m)
Hv = Finished installation height (m) v = Compression ratio

Calculation example: Ap =125m2
Hv =.3m
v = 1.3

L = 125 • .3 • 1.3 =49m3
The dumping height H8 is .3 • 1.3 = .39m