Earth Tube under foundation??

Hi all!
Just curious if anyone has attempted this.  I am interested in building an earth tube when I build my straw bale house but I live in a very rocky area so don’t want to do more digging than necessary!   I’m considering attempting to construct an earth tube that is buried under the stem wall and runs the perimeter of the building.

Anyone tried this?  Any reason why it would/wouldn’t work?

The reason for the foundations is to create a stable foundation for the building.
Running a open pipe directly under the foundation may be a recipe for disaster.
Some questions;
- earth tubes usually start 50 -100M away from the building and come in to it.
- why run it around the perimeter instead of under the foundation and into the house?
- is your ground solid rock, because if it is you could pour a foundation dirctly on it with pins located between the solid rock and the concrete.

Thanks for the reply John.

I don’t think it would be a structural issue with the foundation... many people use perforated 4” pipe as a sort of French drain under their stem wall so this wouldn’t be any different than that.

 When I said run around the perimeter maybe that wasn’t clear.. I meant underneath the stem wall running basically in a circle (or rectangle..) under the wall.  This would give ample distance to allow the air to cool and wouldn’t require any additional digging.  The ground here is not solid rock, just very rocky and some veins of Caliche (a natural cemented rock conglomerate).

Thats clever to use your foundation as the trench for the earth pipe, well done!