reusing wood?

[Mia]

we have salvaged some wood for our house to be - 3/4"  plywood sheets for the roof.  (previously part of another roof.)   any problems with reusing the plywood, as long as it is sound?  it's about 15 to 20 years old.
do we need to remove all the nails from the plywood before using it for roofing?  some pieces have over 100 nails in them.  the building was in a high-wind area.  we were thinking of just pounding over the nails that are too hard to pull.  (you know, there are always some that don't want to let go.)
thank you for any words of wisdom you may have about reusing building materials.    

[Jochen]

As long as it is sound, use it. When the nails do not interfere with your rafter location, plywood laying flat on to the rafter, I can't see a problem with that either. But 3/4" plywood seems to be a little over killed for roof sheeting? And hard to handle due to its weight.

Jochen

[JRR]

Rather than pounding the nails. and the plywood, you may want to use a small grinder.  The most popular grinders are made by Dremel,  ... after having worn out a couple of Dremels, I now prefer the Black & Decker.  

Use the mandrel-mounted 1 1/8" dia flat grinding discs ... and you will zip through those protruding nails ... doing little/no damage to the wood.

[Mia]

I know that 3/4 inch plywood is overkill, but it was free, except for the labor of getting it & grinding off nails.  to buy it we would pay at least $35 a sheet.
multiply by 36 sheets = $1260.00.
thanks for the feedback!  

[williet]

I would pull the nails, or at lease grind off the heads. Over time, the nails have a tendency to back out and this will create leaks.

[Guest]

Consider using a nail puller which pulls nails straight out without damaging material--especially used when wanting to reuse roof shingles (versus a prybar or claw hammer).  Learned about this at ShelterInstitute.com.

http://www.shelterinstitute.com/catalog/product_info.php?cPath=2_60&products_id=234