Which subfloor material for attic redo?
madmadscientist
| Posted in General Discussion on
For the new attic floor project I am working on I need advice on which sub-floor material to use? I don’t require water-proofness as the area is already enclosed. Weight is an issue though. I plan on using 3/4″ T&G just not sure if plywood or OSB or what I should be using. I only need 20 sheets of it so price is not that much of a consideration. I can afford to use good quality stuff.
Thanks,
Daniel Neuman
Oakland CA
Crazy Home Owner
Replies
Use plywood.
An attic? Use 3/4" OSB. Probably even the cheap stuff. I can get it right now at my building supply for $13 plus change. If you have more money than that which you need to part with, send me an E-mail and I'll give you my mailing address.
Good luck,
Matt
Well actually its a subfloor for an attic room that will start out as storage and hopefully end up as a bedroom so I'm not thinking bottom of the barrel OSB is what I want.Daniel Neuman
Oakland CA
Crazy Home Owner
Plywood or Advantech depending on price.
Either will be fine in my opinion, since you will not be leaving it exposed to the weather I'm not if Advantech has any real advantage over plywood.
I'd stay away from traditional OSB.
Am I right in that the difference between advantech plytanium and regular CDX plywood is its weather resistance? I haven't picked up a sheet lately but it seems to me that an OSB product of the same size and strength as a plywood product would have to be heavier?
Of the different flavor of plywoods which is best for this situation? The yard is reccomending 3/4" Sturdi-Floor Plywood to me. Is that overkill?
Thanks,Daniel Neuman
Oakland CA
Crazy Home Owner
To my knowledge the main advantave of Advantech is it's ability to weather well. I'm sure both Advantech and Sturdi-Floor could produce information as to which product is stronger and in what ways. Either one would suit your needs adequatly in my opinion. What is the cost difference between Advantech, Sturdi-Floor, and if they have it, 3/4" CDX T&G?
If it were me I'd go with the least expensive alternative as I think all three will perform equally well in your situation. If you were framing an addition or something that was going to be exposed to the weather for any period of time I'd suggest the Advantech.
I'm not sure what the difference between 3/4" Sturdi-Floor Plywood & standard 3/4" T&G plywood is.
Cag,You wrote, "I'm not sure what the difference between 3/4" Sturdi-Floor Plywood & standard 3/4" T&G plywood is. "I'm not sure either. All the 3/4" T&G I've ever seen was Sturd-i-floor. I do know that the ply just under the top ply is filled on Sturd-i-floor so point loads like high heels won't punch through.Bill
One advantage of OSB, be it Advantec or whatever, over plywood is that it is flatter and therefore easier to install and yields a flatter floor. Lately I've been using a product called Structurewood Edge Gold which is giving me good performance for a slightly lower price than Advantec. I've had 7 houses framed in the last month and a half, so $1.50 a sheet definitely helps as long as I can get good performance from the product I use. This Edge gold stuff (Weyerhaeuser?) hasn't shown any problems and I've been using it on on off for about 2 years. It has a pretty good warranty, although I can't remember the specifics right now. I think it is basically another manufacturer's answer to Huber's Advantec.
These houses get dried in quite quickly though. If I'm building something that I think may get a lot of weather before being dried in I use Advantec.
I do put the cheap OSB in the unfinished attics though, which I think is roughly $8 a sheet less than Advantec. This flooring is installed after the house is dried in. These areas would never be converted to finished space as these are trussed houses. The attic platforms are maybe 8'x12', built on storage trusses, and intended for light storage.
I finished up an apartment complex after another super left the company last year. These buildings got a good amount of weather. The previous super had used plywood on about 1/2 the 7 buildings since it was less expensive for a period about a year and a half ago when the lumber prices were all crazy. The plywood was an ABSOLUTE NIGHTMARE. Specifically, it was so uneven that the ridges were telegraphing through the 1/4" Multiply underlayment that was installed below the VCT floors.
Weather is not the only source of water though. Plumbers routinely spill water in houses as they fill and test their DWV and supply piping systems. Then, after move-in there could always be a plumbing or appliance leak.
Maybe things are different in other lumber markets where different products are available, but I honestly feel that I would be doing my customers a disservice by using plywood.
Thanks guys for the advice. The difference in price is only ~$1.50 so I went with the sturd-i-floor stuff. Picking it all up tomorrow so it can moisture equilibrate for a couple of weeks before I start installing it at the end of december.Daniel Neuman
Oakland CA
Crazy Home Owner
3/4" T&G plywood.