Originally Posted by Neil_K
I have a couple of ponderances that maybe you can tell me why:
1. Why are dimensional boards about an inch longer than they say? Example, my 2"x8"x16' joists were 16'1".
2. OSB for roof decking is staggered and perpendicular to the roof trusses. Why, then, does everyone put OSB on the outside parallel (the 8' side goes UP)?
Just curious. :confused:
I'm not really sure but my guess would be that the boards are made and cut by machine. Most boards are cut to fit for it's installation. The same question would be why did they change all the measurements of would I.E. a 2x4 is actually 1-1/2x3-1/2. When in hte old days they were actually 2x4. I guess it's easier to say even numbers then 1/2" increments. But, again I think it would have something to do with the factory cuts they get.
as for the roof installs. I would also think it would be easier to make a 4'cut then an 8'cut and easier to stagger the joints to break the seems up for a better and more secure fit.
as for the walls I've always installed and seen them installed with the 4'side up. I would think it would be harder to install with the 8' side up especially working on the second story and up.