Platon cavity drain membranes were used to waterproof the 150m2 basement of a substantial four storey new build property in Nottingham.
The basement has two levels, with the higher level leading out to a terrace. The space will be used for a gymnasium, plant room, playroom, store and bath/wet room.
The basement was built from two skins of blockwork, the outer skin being backfilled against with mass concrete, the inner leaf was the load bearing wall for the ground floor and first floor of the property. Tritons technical team assisted the contractor with the specification for the internal cavity drain system, ensuring the design conformed to BS 8102 (2009) Type C drained protection.
When the outer block wall had been constructed on to the newly cast concrete slab, both wall and slab were treated with a single application of Triton TT Vapour membrane. This acted as an anti-lime coating to minimise the risk of free lime build up behind the cavity drain system which could block the pumps. The Platon membrane was then installed to the outer block wall fixed by proprietary fixing plugs and seals and linked in to Aqua Channel drainage conduit installed at the base of the wall. The Aqua Channel will enable any water ingress in the upper basement level to drain in to one of the three sumps created in the lower basement level. The Aqua Channel incorporated inspection ports at changes in direction to provide a maintainable system.
Each sump was fitted with a twin Aqua Pump system, high level alarm and Aqua Pump Pro Battery Back Up Pump. At the top of the outer perimeter wall, the Platon Multi was left extending beyond the full height, enabling it to be trimmed and sealed to the DPM and cavity trays to the ground floor walls.
Platon P20 floor membrane was then installed to a 1m strip around the perimeter and sealed to the Aqua Channel and the Multi membrane on the walls. An inner leaf of block work was then built on to this strip to form a cavity. Once the inner leaf was complete the remainder of the floor was eventually covered with P20 membrane which was then screeded over.
A key advantage of using a cavity drain system is that prior to the installation of the wall and floor finishes, the membrane and drainage system can be fully tested.