Storm Related Water Entry Mitigation Assessments

Water entry through roof fabric, over topping from gutters, flooding from external flow paths, surcharge from stormwater drains or uncontrolled transfer into lower lying areas such as carparks, impact the health and amenity of building occupants and causes long term damage to property.

The correct and ongoing operation of stormwater systems is integral to the sustained effectiveness of a buildings weatherproofing systems to resist the transfer of water internally. The diagnosis of contributing factors to water entry and recommendations for effective measures to mitigate or minimise further occurrences, is one of Watermark Services Group primary speciality field of expertise.

Our integrated knowledge in the specialist fields of hydraulics, external waterproofing & building construction, enables forensic assessment of the weatherproofing requirements of a buildings exterior; in conjunction with the performance capabilities of the stormwater management systems, to determine the modes of failure in the properties storm related water management systems that have contributed to the adverse water related impact to the property.

• Roof drainage – being eaves gutters, box gutters, valley gutters, downpipes and overflow provisions. When incorrectly installed or inadequately sized it may result in overtopping. Overtopping is where the drainage system fills to capacity, failing to transfer rainfall water to a designed point of outfall, with excessive water inflow entering internal areas that should otherwise be protected by the external weatherproofing system.

• Roof cladding and flashings – being the coverings for roof areas, and the flashings that transition between different roofing members, roofing pitches or at transitions to integrated building surfaces. These are the buildings front line to weather proofing. These front-line weather proofing systems are subject to extensive environmental effects, with varying rainfall intensities and cyclic wind pressure effects specific to a properties location or elevation, and exposes any material or installation deficiencies to water transfer, being a compromise in the exterior weatherproofing.

• Surface drainage systems collect and convey rainwater that has fallen on a surface to a suitable point of outfall. The conveyance of stormwater to a point of outfall, prevents water ponding, water flooding and substrate saturation, that will compromise freeboard provisions or waterproofing terminations, resulting in internal water entry. Surface drainage systems are impacted by unsuitably sized systems, inadequately designed systems, systems that incorporate unsuitable materials or systems that have not been correctly maintained.

• Subsurface drainage systems collect and convey rainfall that has infiltrated into substrate surrounding buildings. The removal of subsurface water relieves hydrostatic pressure imposed on below ground building elements minimising impact to structures whilst facilitating the collection of flows to minimise nuisance or health impact. Subsurface drainage systems are impacted by unsuitably sized pump systems, inadequately designed piping systems, holding tanks or wet wells that are not effectively sealed, systems that incorporate unsuitable materials or systems that have not been correctly maintained.