This will work very well for protecting your furniture. Use the ram tape to connect the sheets and blue tape to secure to the table.
38" is 3.16 ft so this roll is 316 sqft
No ... it's heavy, flexible paper. You roll it out, lay it down, tape it together and keep your new floor gorgeous while you finish up the house. Sometimes, we get two uses out of it, but mostly it's a one use product.
Not sure about the 3/16" either... .046" is actually 3/64" or less than 1/16 of an inch -- which makes this closer to thick paper... which is why it doesn't work well on any kind of "thicker" carpet. It probably works great on a hard (or firmer) floors (hardwood, tile, vinyl, laminate, or even short berber carpet etc).
NO! The purpose of underlayment is to stop / minimize moisture from reaching your wood flooring. Use a product called “aqua bar” or even roofing felt
Absolutely. But you'll have to cut it to fit each stair and riser and tape it well. The roll has foldlines precreased running down the length of the roll. Cut your pieces by width (using a razor knife and straight edge) then cut the piece in half for two pieces with foldlines.
The product makes that very claim right on the package. But i would use ram board and add ¼ in sheeting on top. Ram board makes a 4x8 sheet if I'm not mistaken.
Absolutely not. Use exterior paint for outside.