Anyone Build A Shed Before?

[66ChargerHI-PO]

I'm asking because this is my first time doing this. I'm building an 8x15 plastic shed to store my old garden tractors and whatever else in, and for the flooring my stepdad says to get pressure treated plywood because the floor is gonna extend out from where my shed is gonna be, if that makes sense and rot out. BUT my mom's friend says to get 1/2 inch OSB Board. I got the OSB Board, was that a mistake?

Thanks everybody in advance

 

[69 Sleeper Bee]

You better paint the OSB or cover it with aluminum siding or custom bent aluminum to go around the edges in far enough for the shed to sit on it and seal it good.
Bottom line you should have listened to you dad !

 

[ruffcut]

Large mistake! Go with 3/4 inch treated. You won't be sorry. That 1/2 inch OSB won't hold the weight and will rot fast. JMO ruffcut

 

[Big Bad Dad]

OSB is NOT rated for wet or weather exposure. It will start coming apart very quickly after a couple of rains. And the Building Codes specify that ANY wood left exposed outdoors shall be treated.

 

[66ChargerHI-PO]

Oh boy, sob . Now what would I treat it with IF i keep it?

 

[DeltaV]

Place an ad on Craigslist and sell it for more than you paid.

 

[Big Bad Dad]

You cannot treat OSB. It is a sheathing product only in 1/2". MUST be kept dry.

 

[gkent]

You mom's friend is an idiot.

 

[gkent]

Presumably you're building a full frame with pressure treated 2/6's or 2x8's under the plywood, right ?!?!?

 

[66ChargerHI-PO]

It will be sitting on a pressure treated foundation. Mom's friend used to be a carpenter for 50 years, he recommended that if we use this OSB to put plastic or a tarp over it if it's gonna be sticking out like I mentioned in my first post

 

[69 Sleeper Bee]

Oh boy, sob . Now what would I treat it with IF i keep it?

You really can’t as it is meant to be a wall sheathing or roof decking to be covered in something waterproof like house wrap with siding or roof underlayment with shingles.
You can paint it all you want but it won’t last. That’s why I said to cover it with something waterproof.
For floors we always used 3/4” tongue & groove sturdy floor decking

 

[66ChargerHI-PO]

Presumably you're building a full frame with pressure treated 2/6's or 2x8's under the plywood, right ?!?!?

I forgot which ones exactly either 2/6 or 2x8s, but yes they are pressure treated and I just bought some pressure treated 2x4's today

 

[66ChargerHI-PO]

You really can’t as it is meant to be a wall sheathing or roof decking to be covered in something waterproof like house wrap with siding or roof underlayment with shingles.
You can paint it all you want but it won’t last. That’s why I said to cover it with something waterproof

So plastic or a tarp like my mom's friend said would work, maybe paint it then put the tarp or plastic on it for extra protection if there is such a thing?

 

[Kern Dog]

OSB is available in a variety of thicknesses. It is merely chips and chunks of shredded wood that is heated and glued together. Yes, it attracts water like a sponge. A tarp or plastic laying over it will not stop condensation.
Even grain plywood is susceptible to rotting away. Water gets in and delaminates the layers. You'll get bubbling in between the layers eventually. It does last much longer than untreated OSB. Ultimately, the best that I see is the treated grain plywood and some type of linoleum sheeting to let the water roll off. A slope built into the framing will allow water to escape.

 

[Thrashingcows]

Or ditch the plywood flooring and go with simple pine 1x4's. I bought one of those shed packages years ago from...Home Depot?...wanted a custom size so ordered a 10'x20' and modified it to a 12'x16' shed. Anyway the kit came with 1x4's for the flooring and they worked well, might need to add a couple floor joists, or customize the spacing to work with the 1x4's, but nothing that would cause issues with it just been a simple outdoor shed.

 

[69 Sleeper Bee]

So plastic or a tarp like my mom's friend said would work, maybe paint it then put the tarp or plastic on it for extra protection if there is such a thing?

I would get something that will last longer than plastic or a tarp. If you have a metal roofing company around you they can make you something to cover the exposed area pretty inexpensive or maybe they misbent something for another job you could get cheap.
How much is going to be exposed around the shed ? Why not make the floor the same size as the shed and flash around that to protect the edges.

 

[R413]

It is just a mistake to use OSB, the condensation, humidity and weight it will be crumbling to pieces in short order. It’s not the right material for a floor in the driest place on earth.

how many times do you want to do this floor?

 

[VANDAN]

Why not cut the osb off, where exposed, and pour a small concrete slab, or dig it out, stone it, and put down some pavers, or 12×12 's ?

 

[gkent]

go with simple pine 1x4's

Pine ... only slightly less absorbent than OSB !!!

The problem is exacerbated by the fact you have a plastic floor in the shed. Moisture will get under that and it won't dry out - so the floor will rot out underneath the shed even faster than the exposed edges. You're screwed unless you ditch the OSB. Ny the time you invest in any sort of covering (that won't work anyway) you'll have spent more than the cost PT plywood - not to mention the time wasted. The only stuff that "might" save your bacon is something like a good soak of Thompson's Water Seal - over the whole thing.

And 1/2" OSB ... you may as well have cheaped out completely and used 1/4" !!

 

[69 Sleeper Bee]

Why not just put down concrete pavers and set the plastic shed on that. Why do you need a wood floor anyway ?