Storage shed roof underlayment

Is it necessary to use felt paper under my shingles for a new storage shed? It is a good sized shed, 12' X 16', fairly steep (10/12 pitch) with 2x6 rafters, 7/16ths OSB sheathing and laminated shingles. Ive been building it using examples from a few shed and barn books and most of them lay the shingles directly over the sheathing with no felt paper.

Any advice?

Thanks much!

 

IMO, it is ALWAYS advantageous to use felt paper under your shingles. Necessary? Maybe not, provided your shingles never leak. But if one shingle blows off and you don't notice it right away, do you really want to risk leaving out $15 worth of tarpaper if it means you develop a rotton hole in your OSB sheathing?

As an additional note, you'll find that most shingle manufacturers require felt underlayment in the instructions on their packaging. Failure to do so voids their warranty.

 

Thanks xsleeper... What would you use to apply the felt paper... Roofing nails? or Staples?

 

I'd use my cap nailer... but what you use would depend on how soon the shed will be shingled. And I wouldn't use roofing nails. If you'll be felting and then immediately laying the shingles, a hammer tacker stapler will work just fine. If not, or if you expect high winds anytime soon, you'd want to use cap nails, and hand nail them. 16" OC along the bottom, 32" OC along the middle.

You would probably want to felt the first 6 ft, then shingle the first 6 ft... move your roof jacks... felt another 6 ft, shingle another 6 ft... so that you aren't wasting time by moving all around the roof. Felt can wrinkle if left in the elements too long, so that's another reason you'd want to shingle soon after applying it.