Investigating Water Ingress Beneath the House
Our team attended a property in Ashfield NSW 2131 to investigate water entering beneath the house and determine whether the existing stormwater system was contributing to the problem.
A preliminary CCTV inspection of the stormwater pipework was completed to check the existing drainage and establish where the property's downpipes discharged.
Once the drainage layout was understood, a trench was excavated along the external wall from the front corner of the house through to the rear downpipe, reaching approximately the depth of the building foundations.
This provided access to address both moisture against the below-ground wall and groundwater moving through the surrounding soil.
Waterproofing the Below-Ground Wall
The exposed wall was cleaned using high-pressure water jetting before two coats of below-ground waterproofing membrane were applied from the foundation area up to ground level.
Drainage matting and geotextile fabric were then installed to protect the waterproofing during backfilling and form part of the drainage system around the wall.
This created a protective barrier between the below-ground structure and the surrounding wet soil.
Installing Subsoil Drainage Along the Foundations
A 100mm AG pipe wrapped in geotextile fabric was installed along the base of the trench at approximately foundation depth.
The perforated pipe collects groundwater moving through the surrounding soil and gives it a dedicated route away from the house.
The trench was then backfilled with blue metal drainage aggregate, creating a free-draining zone that allows water to move towards the AG pipe rather than remaining trapped against the building.
Connecting the Drainage to the Stormwater System
A new 300mm x 300mm stormwater pit was installed beside the rear downpipe and connected to the property's existing underground stormwater system.
The new AG pipe was connected into this pit, allowing groundwater collected along the foundation to discharge into the existing stormwater drainage.
Once everything was connected, the system was tested and commissioned before the excavated area was reinstated.
For this Ashfield property, combining below-ground waterproofing with subsoil drainage addressed both sides of the problem: helping prevent moisture reaching the wall while also providing groundwater with a pathway away from the house.
Related Stormwater & Drainage Services
Pure Plumbing Professionals provides Stormwater Drainage, Subsoil Drainage, CCTV Drain Inspections and Residential Plumbing services throughout Ashfield and surrounding Sydney suburbs.
This can include AG drains, stormwater pits and other drainage improvements for properties experiencing persistent groundwater, subfloor moisture or water ingress.
