[rockytriton]

I know this sounds weird, but does anyone know anything about digging an expansion room onto your basement? I'm trying to find out any laws that I would have to go through in order to do this...

[Turtle]

___I have only done theoretical work on this, but I have enough deep digging experience to know that above all it is highly dangerous. No doubt codes apply one way or the other, & likely stricter in cities. It may also depend on how you define the room's function as some laws may regard the use, eg bomb shelter vs rumpus room, vs secret room.
___Whatever you do, use caution. That said, digging is way fun! I used to mine &I still treasure hunt with a metal detector. Well, any turtle worth their salt knows how to dig.

[C1ay]

Originally Posted by rockytriton

I know this sounds weird, but does anyone know anything about digging an expansion room onto your basement? I'm trying to find out any laws that I would have to go through in order to do this...

Have you tried asking your local building inspector? Any laws regarding this will be local ordinances.

[rockytriton]

No I haven't asked any building inspectors. I tried searching for info on the web but, surprisingly came up with nothing. I doubt anyone would actually allow it, but who knows if they could find out about a small secret room.

[Buffy]

Below-grade construction is highly non-trivial. The house I grew up in had a "owner-constructed" downstairs (it was on a hillside, so the downstairs was outside on one end and mostly underground on the other). It was properly constructed physically with retaining walls and such, but it became an indoor pool whenever it rained. Of course since it never rains in Southern California, this was a problem only a few times a year, but I got good at moving everything out of the room every time it rained.... You need major sealing *under* the foundation in order to avoid this problem and its really best done by experts....

Cheers,
Buffy

[C1ay]

Originally Posted by rockytriton

No I haven't asked any building inspectors. I tried searching for info on the web but, surprisingly came up with nothing. I doubt anyone would actually allow it, but who knows if they could find out about a small secret room.

I think it would be allowed if it didn't weaken the existing structure. It's just one of those things that depend on many variables that only a local building person can answer for you, especially if you are digging a passage under a load bearing wall.