Downpipes Not Connected to Storm Water
One or more downpipes discharge directly onto the ground at the building perimeter rather than into a stormwater system. Water concentrates against footings, raising the risk of footing movement, rising damp, and termite conducive conditions - we find this in 22.1% of all Perth inspection reports.
Severity rationale
The modal score is 3, accounting for 69.7% of the 1,718 observations. Score 4 represents 23.8% of findings - typically where discharge is occurring directly against footings or where rising damp and termite-conducive conditions are already visible. Score 2 covers 6.5% and score 1 is essentially absent (0.06%). The absence of any score 5 reflects that damage potential is real but unfolds over seasons rather than immediately.
Causes
- Original installation never included a stormwater connection - common on older suburban builds
- Downpipe disconnected from underground drain during landscaping or paving works
- Improper or incomplete connection left at the time of construction
- Underground drain collapsed or blocked, prompting the downpipe to be capped off at ground level
- Additions or pergolas fitted with gutters that were never plumbed to the stormwater network
Symptoms to look for
- Downpipe terminating above ground with no visible connection to an underground drain or soakwell
- Saturated or eroded soil immediately below a downpipe outlet
- Ponding water near external footings during and after rainfall
- Efflorescence or moisture staining on external masonry near footing level
- Elevated termite risk where discharged water contacts timber wall plates or slab edge
Remedies
- Engage a roof plumber to scope and price connection of all unconnected downpipes to the stormwater system
- Where underground drains are absent, engage a landscaper to install soakwells or a perimeter drain to direct water away from footings
- Check existing stormwater drains for blockages before investing in new pipework
- Re-grade any soft landscaping around discharge points so surface water flows away from the building
Where we see this most
These suburbs show the highest concentration of downpipes not connected to storm water in our inspection data (minimum five observations). Click a suburb to see its full defect profile.
Worth asking our inspector about this specifically.
This is a contributing factor rather than an emergency, but the longer water discharges against footings the higher the cumulative risk of footing movement and termite conducive conditions. Rectify before the next wet season where possible.