Connecting downpipes

Importance of Connecting Downpipes

Connecting downpipes is crucial, especially in South Australia, where many homes are built on highly reactive clay soils (H1 & H2). These soils swell when wet and shrink when dry, making Adelaide’s soil some of the most reactive in the country. Controlling moisture around your home is essential to prevent soil movement. Keeping moisture levels consistent throughout the year means watering around your home during droughts and ensuring stormwater drains into the street or sumps.

Soil Movement and Moisture Control

The table below shows typical soil movement at a site, which can be minimized by controlling moisture and connecting downpipes.

Downpipes: A Standard Practice

For the past 40 years, connecting downpipes has been standard practice. However, many older homes still have downpipes discharging water near the footings. In most cases, houses without connected downpipes also show diagonal cracks, as seen in the video.

How to Connect Downpipes

Connecting downpipes to stormwater drains is a simple process. You may need to remove sections of paving to run pipes to the street. The cost is typically around $3,000. This is another reason to schedule a pre-purchase building inspection before buying.

Dealing with Leakage in Old Pipelines

Leakage is common in old earthenware pipelines, which are vulnerable to soil movement and tree roots. If you suspect leakage is causing cracking or rising damp, upgrading to a new PVC system might be necessary.

Testing for Leaks Before Replacement

Before replacing old drains, ask a plumber to block the pipe and perform a static water test to check for leaks—it may still be in good condition.