Figure 1: Vandex Expaseal expanding waterstop used in a newbuild concrete basement
Vandex Expaseal is used to waterproof construction joints or pipe inlets in concrete structures exposed to permenent or temporary hydrostatic water pressure (e.g. basements). When in contact with water, Vandex Expaseal expands more than 300% to form a positive seal against the concrete surrounding the construction joint which is resistant to water pressure up to 7 bar.
Figure 1 shows a typical reinforced concrete basement. Vandex Expaseal is fixed to the concrete slab before the concrete wall is poured using Vandex Uniflex adhesive. Vandex Expaseal is also used to form a seal between wall sections poured at different times.
Rain Protection Coating
When using expanding waterstops, it is essential to ensure that the waterstop does not have a chance to swell before it is covered in concrete. This can occur, for example, when the waterstop is fixed in place on a concrete slab and there is a period of rainfall before it is possible to pour the wall sections.
Vandex Expaseal gets round this problem as it is covered in a waterproof coating, protecting it from rainfall for a period of 2 – 3 days. Once Vandex Expaseal is covered in concrete, the alkalinity of the concrete dissolves the coating allowing the waterstop to function normally.
Vandex Expaseal contains crystalline-active additives similar to those found in Vandex Super which enhance its waterproofing properties.
Suggested NBS specification clause: E40-310
Visit our NBS page for further information on specifying Safeguard products using NBS.