Is it necessary to put screws into the sub-flooring to prevent squeaks with hardwood? If so, how many per square foot? (I seem to remember hearing about this, and I remember "noisy" areas in my parents' hardwood floors.
Answer:
Depending on the age of the house, you might have T&G pine for sub-flooring or sheet plywood. The T&G I nail down with two 2-1/2" spiral nails in every joist in every board and on the plywood I use 1-1/2" plywood nails every six inches within the field of the sheet and every three inches along the butted edges.
