Originally Posted by Dilton Doiley,Philosopher King
Assuming that a) I own my house b) I don't hit any water, sewage, or power lines and c) digging under my house won't affect the structural integrity of my house or its foundation, how far down can I dig, from a legal perspective? Can I build a five story house under my own two story home?
I am imagining something like... digging a stairwell out in my basement floor, and then digging out rooms and whatnot, farther and farther down.
Additionally, if I am able to dig down to a certain depth, can I start to dig out, essentially under all the houses in the neighborhood, but so far down they would never know (unless they also dug under their houses) with no legal repercussions?
In most jurisdictions of the U.S., from a legal perspective, you own the land within your property boundaries all the way down to the center of the Earth. The exception are properties where the mineral rights are severed from the remainder of the real estate rights (generally only an issue in western states).
Any water, sewer, or power lines on your property (not owned by you) should have an easement.
You cannot dig under someone's house or anywhere else on their property without an easement.
With respect to this last question, I am actually involved in a project that will involve tunneling under people's houses, businesses, a railroad line, etc. We are installing several deep sewage tunnels that will run between 30 feet below grade to as deep as 150 feet below grade. Some of the tunnels are being bored in soil, and some are being bored in bedrock, and they will be several miles long. Anyway, we have to get easements from every property owner on whose property we tunnel under, regardless of the depth of our tunnel.