Void Formers / Bolt Boxes

Dinstock’s void formers reduce a lot of excess weight in a variety of structures including foundations and embankments.

cylindrical mesh wire void former

Wire Mesh Sleeves

polystyrene void former shaped as a cone

Polystyrene Cones

hollow cardboard cone void former waxed

Hollow Waxed Card Cones

POLY CONES – Product Code: Wire Mesh Sleeves
BOLT BOXES – Product Code: Polystyrene Cones
WAXED CONES – Product Code: Waxed Card Cones

When installing foundation bolting, specifically SSOX, instances arise where a pocket or void is required around the bolt, to allow for easier adjustment even after the concrete has been poured and set.

The former is simply placed over the inverted bolt, fitting flush with the plate washer or anchorage. The formers can be left in situ until the concrete has set or in the later stages of the concrete setting when the former can be rotated, breaking the bond with the concrete and removed allowing for grouting around the anchor after setting the bolts in their final position.

We offer three alternative products for this purpose in Polystyrene Tapered Cones, Hollow Waxed Card Cones, cylindrical ‘Expamet’ wire mesh sleeves.



Polystyrene Cone Void former

Polystyrene cone void formers are mostly used as a lightweight material for forming voids & openings within concrete structures. They reduce a lot of excess weight in a variety of structures which include precast flooring beams, motorway bridges, underpasses, shopping centers, foundations, and embankments. Dinstock void formers, therefore, are suitable for domestic and commercial applications.

Waxed Cardboard Cones

Manufactured from waxed cardboard, Dinstocks waxed cardboard cones are used to position Holding Down Bolts in concrete bases, fix steel or timber frame buildings or structures. to provide movement and adjustment of the bolts.

Wire Mesh Sleeves/tubes

An expanded metal mesh or tube used for positioning holding down bolts in situations where the bolt box is to remain in the concrete. Wire Mesh Sleeve/tube formers are ideal as a low-cost, lightweight, non-porous cell former within concrete bridge decks and can also be used as column formers, test caps, and bolt boxes.