Good Morning all... DD .vs. OSB/drywall... Does that tiny extra bit of density that 5/8 drywall has really out weight the perks of a 3/4 OSB first layer?
I have spent the last couple of hours searching here on AVS and using the modern miracle that is google. Trying to determine why I would want to build my HT internal walls with 5/8" DD, over a combo of 3/4" (23/32) OSB and 5/8 drywall. (for sake of discussion lets assume both utilize GG
Seeing as the vast majority of builds posted here that use a multi-layered leaf, also use drywall exclusively. I thought I'd pose the question as it's own thread so many can throw their two cents in without cluttering up individual members builds.Here's my logic for giving OSB the nod:
In my particular room, I have loosely calculated that all four walls and ceiling will take 36 4x8 sheets to cover.
So a single layer of 5/8 drywall will cost roughly: $330cdn (w/o tax)
A single layer of 3/4 OSB will be in the ball park of: $442cdn (w/o tax)
Now sure, there's an additional $112 to the budget that doesn't need to be there. However, for all of those who hung their own drywall. Would it be worth $100 to you if you never needed to worry about hitting that stud while doing that second layer..? Or not needing to buy a box of extra long screws to reach those studs..?
I'm also weighing in the possible savings of going to 24" centers as compared to 16" for the wall construction. That in itself cuts the OSB's added expense by 50%. I'm also hoping (feel free to comment), that the use of OSB as a first layer, will give my true room in room build enough added structural strength as to eliminate the need of any ties/clips (eg: flanking paths) to surrounding structure for support.
As far as the density of each material. The best I could find for OSB was this:
Found here: http://www.cwc.ca/NR/rdonlyres/F6074...559E/0/OSB.pdf
...and for drywall:
Found here: http://pabcogypsum.paccoast.com/pabc...GA-235-01b.pdf
So we have a hard number for OSB, at 40lbs/cu.ft. Using those tables, drywall only has about a 2lb advantage in weight per 4x8 sheet. However it is 1/8 thinner in dimension. Which makes me believe it does have more density. Unfortunately I don't possess the math skills to determine how much. Although, I can't really see it being all that much.
So after all my digging, the only positive I can come up with for the exclusive use of drywall is what I believe to be a slightly extra bit of density. How much of a benefit is that extra bit...? That's what I want to know.
If anyone in the know has some information as to why DD is the more supported construction methodology, please comment. I just can't believe that 1/8 difference in thickness trumps all the advantages a first layer of OSB provides.
Any, and all comments welcome.
Thanks in advance...