The Problem
Groundwater entering the lower level of the building causing dampness and mould. When we first inspected this property we were told that the owner had already spent a lot of money — over $100,000 — and the problem had not been fixed. The previous contractor had excavated right across the front of the property approximately one metre deep, installed an ag drain and then concreted over everything. This caused considerable disruption to the use of the house. A lot of wasted money and effort did nothing to stop the house from being affected by ground water.
Understanding the Water Source
To understand why the previous approach failed, it is necessary to have a brief look at Australian natural history.
Gum trees in this country do not die in drought. Anywhere from Western Australia to north Queensland, gum trees survive through even the driest conditions. They have a wide but shallow root system — as you can see if one blows over — and effectively live on the top metre of soil. If there is no moisture in the top metre of soil then the tree puts down a tap root to source some moisture. This does not have to be directly under the tree; the root can travel laterally to find the moisture.
This moisture seam is only about half a metre wide, is normally between three and five metres below natural ground, and moves on top of a rock layer. It has been there for millions of years.
Finding the Real Depth
This is the moisture the Hygro Seepage Control system deals with. We identified where the moisture seam was situated, excavated down until we located it, and then continued our excavation for another half metre to install our system.
The initial contractor installed the drain at 1 metre depth. We encountered the water at 2 metres depth. Prior to excavation we do not know exactly how deep the water is, but we believe the water does not have a tape measure so it does not know how deep it is either. We do know that if this water had been 5 metres deep, then it would pass harmlessly under the house and no one would know it was there.
The Result
In this instance we installed three systems — in 90% of cases one is sufficient — and the home has been dry ever since. What over $100,000 in conventional drainage failed to achieve, the Hygro Seepage Control system resolved by addressing the actual source of the problem at the correct depth.
"Since installing the Hygro Seepage Control system over two years ago we have had no water entering our property — even during cyclonic rain in 2025. Hearing the water being pumped out during heavy rain is joyful confirmation that our property will stay dry."
— Elizabeth S, Kenmore