Long story short. We hired a structural engineer. He identified in the main effected area we have a 62 mm heave in our raft slab. We have excellent drainage.
What we've tested:
- Stormwater system which failed, but only during pressure testing and the failures were on top of the pipes (cracks). Not what we believe is the cause/source of water coming in as we fixed the item and are still having issues.
- Tube tested on neighbours side fence next to his pool. No water came in.
- Dye tested neighbours stormwater system next to problem area of house. No joy.
- Sewerage and hot water service tested all fine.
- When we dug boreholes along our neighbours fence the clay soil was saturated at a depth of about 300mm. The boreholes right against our slab were moist but not saturated. At a depth of 700 against the house we hit virgin dirt which is dry.
- Some further things to make life difficult, our house and our 4 neighbours along have the same issues. There is a water bore hole about 100 metres from our house. Not sure if it's been decommissioned.
- One of the neighbours approx. 4 months ago had a water main burst in there front yard.
Structural engineer can't figure it out.... I'm out of ideas. Can anyone please help?
Sorry for the short story/lack of details I'm just exhausted... Happy to provide any further info.