Project Details
Fiona Brooke of Architects Fiona Brooke & Partners contacted John Newton & Company regarding the waterproofing of the earth retained elements of a sizeable extension to The Old Vicarage in Hughenden, Buckinghamshire.

During initial discussions, where various waterproofing systems where considered, it was decided that a combination of Newton 301 AquaProof waterbar and Newton 403 HydroBond external membrane would be ideal, as it would create a combined Type A & Type B waterproofing solution.

Methodology
Newton 301 AquaProof is a metal waterbar that is fixed to the reinforcing steel prior to concrete pour and so becomes fully embedded within both concrete elements of the construction joint to form a physical barrier to water. Newton 301 AquaProof forms a fully waterproof barrier at construction and does not require water to seal the joint as is the case with conventional hydrophilic waterbars.

Newton 403 HydroBond was applied above the blinding and fixed to the shuttering prior to the concrete being placed. The fleece surface of the membrane engages into the wet concrete and becomes homogenous with the concrete structure preventing water, if it were to enter via a small defect, from moving to the construction joints.

Additionally, 403 HydroBond has a self-healing coating that re-seals any holes that may occur to the membrane and so provides a very robust external membrane.

Result
Both the 301 AquaProof and the 403 HydroBond are pre-applied allowing for normal construction techniques to be used by the site personnel, resulting in a fully watertight construction that required no further waterproofing after the placing of the concrete.

The installing contractors, RK Construction, Buckinghamshire, having previously used a Bentonite derived system commented on how light and easy to handle the Hydrobond was, making installation and detailing at corners and pipe penetrations a breeze in comparison. It was also noted that when rained on, the material did not become heavier and slippery to walk on which was cited as a real benefit compared to the previous system.