Dry Waterproofing Ltd was contracted by Simon Knox, the principle architect of Knox Bhavan Architects LLP based in South East London to undertake waterproofing works within the basement at Mill Lane.
The Victorian property had been unoccupied for several years and was being refurbished. This included lowering and extending the existing basement to give more headroom and space for new bedrooms also a bathroom and storage facility.
To start, the basement was excavated to the required depth. Then new reinforced concrete support walls and a basement floor slab were constructed. The existing brick walls were also underpinned by the main contractor.
The property is situated on a sloping site and therefore the effect of lowering the basement meant that ground water began seeping through the horizontal seam between the new under pinning and existing brickwork, also through sections of several vertical construction joints and at the wall/floor junctions.
To deal with this problem, we first used Newton Waterplug Compound to initially ‘plug’ the weeping fissures and joints, and then applied Newton 101F cementitious slurry to stop the water ingress. A more sympathetic approach and long term control measure was then introduced using the Newton 508 studded cavity membrane to the walls and floor, incorporating Newton perimeter drainage channels (BaseDrain) with jetting ports, and the Newton sump and pump drainage with battery back-up facility.