Depends on where you live. Most use 15 now. Check with the Building Inspector in your area.
30# felt is thicker..... Better?
I doubt either is necessary on second floor. Rosin paper is cheaper than felt. I would probably use either #15 or #30 felt.
15% of 200 lbs is 30 lbs.
it depends on the shingles, regelar 3 tab shingles use 15 lb felt, archatectual requires 30 lb felt and sheet metal requires 30 lb felt. but always check on the shingle package and your local building codes for specs
15% of 200 lbs is 30 lbs.
15# typically covers 4 SQ 30# typically covers 2 SQ
15 lb. has 400 sq. ft. per roll and 30 lb. has 200.
type I is 15# felt and type II is 30# felt
60 minute building paper is used to build..
15 to 30 ft lbs
Both my dad(46 years old) and I (17 years old) do p90x. My dad uses the 15 lbs, 20 lbs, 30 lbs, and 35 lbs. I use the 8 lbs, 10 lbs, 15 lbs. It depends on the type of work out.
That is approximately 1/15 of a pound.