A new development of an 11 storey, 270 bed student accommodation scheme including leisure facilities at ground floor level, built on the site of the old Bristol Post newspaper printing press hall. The press hall was demolished, and the new building was to use the existing foundations and basement to extend capacity. This basement area required waterproofing to achieve a Grade 3 environment, to prevent the ingress of water, as defined in BS8102:2009.
atal were engaged at design stage to act as waterproofing experts, providing details and a specification to meet the project specific criteria. Materials were delivered to site and operatives were trained by atal staff into the installation of the systems.
After numerous visits by atal staff to monitor the waterproofing installation, answer questions and provide bespoke detailing a dry basement was achieved.
David Rees CSSW
Ian Price CSSW
To achieve a Grade 3 environment as defined in BS8102:2009 a combined waterproofing system was specified.
atal Bentofix 5000, a Type A waterproofing membrane consisting of two polypropylene geotextiles enclosing powdered Sodium Bentonite clay, was specified to the face of contiguous piles. atal Bentofix 5000 can be installed during inclement weather and requires little surface preparation. As the membrane was applied prior to the pouring of concrete a fully bonded waterproofing system was achieved.
BS8102:2009 states the need to assume defects in the waterproofing installation and the consequence of defect. The consequence of water ingress would severe as a Grade 3 environment was required. A cavity drain system was specified to lower the risk of water ingress. atal Flo Board 508iR, a Type C membrane consisting of a translucent high-density polyethylene (HDPE) sheet with molded studs, was specified internally.
‘Project architects, RDA liaised with atal to bring forward a set of waterproofing and tanking details to ensure a water tight lower ground floor level within the setting of the original Bristol Evening Post print factory basement. atal provided us with design drawings and specifications founded on their product range comprehensive industry experience, with which we were able to confidently develop our working drawing package.’ – Rich Brown – Russ Drage Architects