A complex structural waterproofing
design for new build mews properties
Triton has supplied a range of
waterproofing systems, plus
technical support, to a West
London new build project
comprising two adjoining, high
spec mews properties. This was a
compact site requiring a complex
waterproofing design for a multilevel basement comprising lift
pits and two swimming pools
recessed into the lower basement
level. In view of the value of
the properties and the variable
water table, a combination of
Types A, B and C waterproofing
systems was specified to produce
a robust solution, conforming to
the Grade 3 basement category
as defined in BS 8102:2009, that
would inhibit any potential water
ingress.
Each property will benefit from a
two storey basement, the lower
basement in each housing a
swimming pool, media room,
gym and plant room.
Archetech - Issue 20 [Page 20]
The basements were constructed
using watertight concrete, with
an external bentonite system
installed as the first line of
defence against moisture ingress,
prior to the placement of the
concrete. A continuous and
linked internal waterproofing
system was then installed using
cavity drain membranes and
liquid/cementitous applied
materials.
Cavity drain membranes were
installed to all earth retaining
perimeter walls and the lower
basement slab. The system
is designed to drain down
from upper to lower level via
discharge outlets from the
bunded perimeter drainage
channel at the upper level. At the
lower level a recessed channel
accommodates a continuous
drainage conduit around the
perimeter of both properties
and is waterproofed with
Triton’s liquid applied TT Vapour
Membrane. Rodding eyes were
installed at 10LM intervals and
at every change of direction to
facilitate maintenance of the
drainage system. The system
drains to sumps in each property
each fitted with Triton’s mains
powered, twin Aqua Pump Pro
system.
The swimming pools, plant
rooms, service trenches and lift
pits are recessed into the lower
basement level forming in effect
a third basement level. Both
pools and all walls at this level are
waterproofed using Triton’s TT55,
a cementitious liquid applied
membrane combined with TTME
elasticiser to accommodate
changes in pressure caused by
emptying and filling the pools
and the noise and vibration from
the lifts. A cavity drained system
cannot be punctured so this
system also facilitates the resin
fixing of heavy plant to the walls
in the plant rooms and service
trenches.
Swimming pool recessed into lower basement level floor.
Perimeter drainage channel at floor level runs around top of
pool liner wall. Pool walls and floors are waterproofed with
TT55/TTME with Fillet Seal detail at wall/floor joints.
The perimeter drainage channel
at floor level of the lower
basement continues at the
same level around the top of the
swimming pool liner walls and
discharges behind the walls of
the trenches and plant rooms to
either of the two sumps recessed
in each plant room floor. Platon
P20 membrane continues the
sealed cavity drained system
across the floors of the plant
room and service trenches.
The bunded upstands at floor
wall junctions, and other wall/
floor and wall/soffit details are
sealed with Triton’s liquid applied
TT Vapour Membrane and Corner
Strip sealing material to create
a complete and continuous
internal waterproofing system
across all substrates and levels of
the basement.
Triton Systems 01322 318830
tritonsystems.co.uk
Upper basement level showing P8 membrane to walls and
bunded perimeter drainage channel.