Externally Applied Waterproofing Systems
Delta Membrane Systems
Geo-Drain Quattro – Drainage & Protection Membrane
Geo-Drain Quattro is a unique drainage protection system/external waterproofing membrane that works in conjunction with Type A External Waterproofing or can simply be used in civil engineering situations. Geo-Drain Quattro is a compact 4-layer membrane which can be used vertically and/or horizontally.
It offers maximum safety for thick viscoelastic coatings and a multitude of alternate Type A systems. Even when driving rain can penetrate through an imperfectly installed upper edge trim.
In a watertight system, rainwater would exert hydrostatic pressure on the waterproof coating. However, the micro-perforated slip film which together with the additional filter cloth, acts as a backup drainage layer behind the dimpled sheet ensures that any water is drained off safely. The slip film prevents the transmission of movement to the waterproof coating.
NP Drain Geocomposite Membrane
NP Drain is an external waterproofing membrane that drains groundwater away from your property reducing the hydrostatic pressure (water pressure). A compact two-layer geocomposite membrane which offers high drainage capacity through specially-configured dimples.
Offers dependable vertical and horizontal drainage in civil engineering, buildings, tunnels and retaining walls. NP Drain protects garden roofs over underground structures, basements and green roof parking decks from moisture. The dimpled sheet prevents water logging and offers great protection from root penetration, whilst the geotextile layer filters out fine particles thus ensuring constant flow of water to drains and discharge point.
With its high compressive strength (150 kN/m2), this drainage and waterproofing system solves every problem.
Terraxx – Protection and Drainage System for Horizontal Application
Terraxx is a dimpled sheet with a geotextile layer which acts as a surface layer. Usually used as a green roof external drainage layer which also protects the primary waterproofing applied to substrate prior.
Laminated on to the dimpled sheet, a layer of compression-resistant permanent filtration geotextile prevents the dimple structure from being clogged up by sludge, guaranteeing optimum drainage in the long run.
Terraxx is an external membrane that can be used vertically and horizontally. The membrane has an adhesive tape manufactured on one side to overlap and join to the next part of membrane.
Floraxx Top – External Drainage Membrane suitable for Green Roofs
Floraxx Top is a water-retaining drainage sheet with an integrated geotextile for perfect green roofs. It has innovative octagonal dimples for compressive strength. There is one sheet for drainage, water storage, and filtration, making it easy and quick to lay out straight from the roll.
Its octagonal dimples additionally reinforced by ribs make it unusually compression-resistant, so that it will sustain even heavy loads safely. It provides an extremely serviceable and economical foundation for green roofs.
Type A Protection Barrier Protection
Barrier protection is materials which offer a barrier to the passage of water with the aim of keeping the target environment within a defined level of ‘dryness’.
BS8102:2009 code of practice for the protection of below ground structures against water from the ground provides guidance on methods which can be adopted to deal with and prevent the entry of water from the ground into a structure that is below ground level. It is wide referred to and used in basement waterproofing, reference should be given to the adoption of a design team, water table classification and defects and remedial measures.
Type A systems can be utilised for several applications:
• New build basements
• Basement refurbishment
• Semi basements
• Storage or plant rooms
• Car parks
• Retaining walls
• Swimming pools
• Lift pits
• Service ducts or similar that are connected to the below ground structure
• Podium decks
• External walls where the lowest finished floor level is generally less than 150mm higher than the external ground level.
Type A waterproofing tightness relies on the effectiveness of the waterproofing system, the preparation, the application and the structure. If a structure is likely to be within a high-water table any defects in the waterproofing barrier could allow water to penetrate causing free water to enter. If this water is not removed, the structure will fill to the level of the water table.
In all cases, manufacturer’s guidance and recommendations should be followed, unless any bespoke details have been confirmed with all relevant parties.
Barrier systems may be applied on either the positive side or negative side of the structure, sometimes also sandwiched within the structure.