Retail Unit in Liverpool
Overview
NJSR consulted RIW regarding a new retail development complete with basement in the heart of Liverpool city centre.
Architect: NJSR Chartered Architects LLP
Client: National Retailer
Contractor: Wates Retail
Applicator: Lainton Services
Principle Application: Internal Tanking
Products Used: RIW Cavity Drain, RIW Aqua Channel, RIW Cementseal
The Challenge
This city centre location provided a difficult waterproofing challenge. The site was surrounded on two sides by Grade II listed buildings, with a pedestrian plaza on the two remaining sides. The proximity of the buildings and adjacent pedestrianized areas meant that an externally applied membrane and external drainage solution was not possible. Added to this, contiguous concrete piles and a single leaf of blockwork internally meant internal tanking solutions were limited. The depth of the basement also provided a challenge as the floor level of the basement was below the level of existing drains.
The Solution
RIW’s design strategy applied RIW Cavity Drain R20 directly to the contiguous piles. As the product is manufactured from HDPE, it is therefore able to follow the irregular surface and curvature of concrete piles. RIW Aqua Channel along with RIW battery backed Sumps and Pumps were used to collect and pump away ground water to higher level drains, with RIW Cementseal being applied to capping beams and linked to the RIW Cavity Drain using RIW Overtape.
RIW Sheetseal 226 was also used internally to protect the floor and was linked to the vertical application of the RIW Cavity Drain. The initial application of the Cavity Drain and commissioning of the Sumps and Pumps early in the construction programme meant that the basement was kept dry during the remaining construction programme. This also meant that the internal application of the Sheetseal 226 was carried out in a drier controlled environment.
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Last Updated: 2026-03-22
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