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How Void Forming Works?

Discover how our innovative honeycomb board creates a technically sound void former.


Analysis of the site

When building on soil foundations, analysis will be undertaken to determine the suitability of the site and whether or not the foundations will need protecting. Shrinkable soils are classified by a plasticity index, which can be continually affected by even the smallest of things. Removing a single tree will add as much as 150L of water a day to the surrounding soil, which is likely to cause ground movement.

Choosing the protection

Depending on the level of heave indicated by the plasticity index, an architect or specifier will need a void former that will protect the foundations of the structure from ground movement. Our void former system is made from 100% recyclable honeycomb. It is delivered to site on a weather proof pallet to ensure the boards are protected from the elements during storage.

Forming the Void

They’re then laid at the necessary thickness, and a concrete foundation is then poured on top. It has a high load bearing ability and is 30% slimmer than competitor products, saving clients money on soil excavation and removal costs.

Saving you Money

Water is then introduced to the honeycomb, creating very little compression and virtually no uplift, and its compressive strength is effectively switched off. As our boards create very little compression and virtually no uplift, there’s no need for clients to calculate fail and safe loads with our void formers. This means that less rebar steel is required across the whole foundation site, which can be a significant further saving.


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