So cute on how the ONE spot you don't want the dog to be has to be the spot the dog decided to plant his/her but down ... leaning on the solar panel ... so cute ... lol :)
We're in a very specific situation here. We've only got four to six inches of soil on top of a solid rock base where we are. But yes, usually you go below the frost line for any building that matters. Technically there's nothing wrong with digging down to untouched Earth only whether it's below the frost line or not but it will shift slightly over time because of the frost. But there again that's where a dry stack foundation really shines unlike other foundations some amount of movement won't hurt these.
