Mapei solutions have been used to waterproof and protect fire control and ventilation systems at HS2’s Westgate Headhouse in West London. The works on the Northolt Tunnel route were delivered by Byrne Bros for SCS JV. All Mapei products were supplied by BlueBay Building Products Ltd.
Situated adjacent to Hanger Lane roundabout, the Westgate Headhouse is sited at the top of a ventilation shaft which regulates air quality and temperature within the tunnel – 35 meters below – and, in the event of fire, allows extraction of smoke. Above ground, the rectangular headhouse contains fire control and ventilation systems for the railway tunnels below. A green roof and landscaping along the line help the new structure blend into its surroundings.
Four Mapei products were used to waterproof and protect the headhouse and its contents. Before pouring concrete, Mapeproof AL AP pre-applied, fully bonded, self-adhering HDPE waterproofing membrane was applied; upon contact with concrete, the robust membrane forms a monolithic bond. Mapeproof AL 1200 AP – a HDPE self-adhesive waterproof membrane - was then post applied, followed by the application of waterproofing Mapeproof Liquid Membrane – a polyurethane elastomeric, thixotropic membrane used to seal, fill and detail. All of the concrete construction joints were made fully watertight with Idrostop 10 hydrophilic expanding rubber profiles.
Following the Westgate Headhouse installation, Mapei systems have also been specified by SCS across various HS2 sites in London.
For more information, please contact: info@mapei.co.uk or visit www.mapei.co.uk