Addition on piers
I am building a ground floor 8X10 laundry room addition on piers, so the underneath will be open to the outside. How do I prevent the water pipes I run from freezing in Winter (I am in MA). How best to insulate this floor, cut up styrofoam for between the joists, fiberglass with plastic cover facing the soil, other? Any other issues? Thanks.
You can use fiberglass but keep the plastic or vapor barrier facing toward the living space (up on the floor) not toward the ground. You can use wire or nylon mesh underneath to keep critters out of the insulation, or a woven nylon fabric, but whatever you use facing the ground should be able to breath.
Use electric heat tape and pipe insulation to wrap any pipes that are below the floor insulation to keep them from freezing.