I have some pipes that I believe can use some insulating or sound
proofing. Before I start a project that I can't finish, I need to find
out the layout of the plumbing hidden inside the floor and some walls.
I'm willing to cut and patch a small number of (small) holes to evaluate
the feasibility of the project, but not more than that. What is the best
way to find out how pipes (and perhaps cables too) are run when they're