particle board or plywood for underlayment?

Guest User
10/15/2007
I am planning on using 1/2" decking and 1x6" for lathes,(I've got plenty of 1x6", my father owns a woodmizer) with 30lb. felt between lath and deck. Most places now use particle board around here for decking. My main concern is which will hold a screw better? I will be screwing the metal roofing down to the lath and into the decking for strength. If a hurican or tornado takes the roof I want it to take everything. Thanks
Guest User
10/16/2007
Will, I haven't ever done any of the screw pull out tests on OSB(wafer board-- not particle board) or plywood. It takes a special tool to measure the 'pullout' force. But you can take a nail, like a 12d or 16d, drive it into waferboard and plywood, wiggle it around then try to pull it out. It comes out of the waferboard a lot easier than it does plywood. Plywood holds better. Also, the manuals I have always seen for vertical panels used to state(it may have changed) that wind uplift was only warrantied when the panel was installed over at least 1/2inch plywood and the correct number of fasteners.
Todd Miller
Classic Products, Inc.
10/18/2007
I would agree in that most manufacturers have tested their products over plywood and not OSB or dimensional lumber However, I will say that in our internal tests using either screws or some sort of ring or spiral shank nail (and NOT smooth shank nails), we have seen similar results between OSB and plywood. However, over time, I do believe that the strength of OSB will diminish faster with heat and moisture than will the strength of CDX plywood. It has also been my experience that dimensional lumber will hold better than any engineered lumber.
Guest User
10/18/2007
Thanks, I was wondering what differance if any. From what I've seen I've not been real impressed with the 1/2" plywood availible here. But I've no experiance with OSB.
Todd Miller
Classic Products, Inc.
10/19/2007
All Best.
Find a Contractor

Get Started Today

Take the first step to increasing the value of your home with a great looking, durable, fire resistant and energy efficient metal roof. Browse our list of qualified MRA Member Roofing Contractors in your area for a free consultation and estimate.