Osb longevity

[Rio_Grande]

I am going to build a few 8x8 deer blinds this year and in an effort to keep the prices down I was thinking about using 7/16 osb which is about 1/3 the price of standard sheeting. Just wondering if we paint the osb how long could we expect it to last?

 

[OZisKTB]

Lots of literature showing OSB is as good or better than plywood. My experience is OSB fails quickly through swelling edges if not protected from water exposure. If your OSB will have the edges, even painted, exposed I'd think of different sheathing.

 

[tcartwri]

About a year.

 

[Gary Fowler]

At about 15 to 30 bucks a gallon for paint, it doesn't take much to make up the price difference to a marine grade of plywood that will last years and years without any paint. I never liked OSB as I always found that small pieces always de-laminate and turn into large splinters ready to injure you.

 

[MacLawn]

I wouldn't use the mess for outdoor. All the work, gone sooner than ye think, the ye have to do job again. Like they say, pay now or pay later.

 

[/pine]

[off topic]
When OSB first came out as a sheathing alternative to plywood the fact that it could be laid either across or with the framing members made it somewhat desirable because it saved some waste...however it was very slick on both sides and made it unsafe to walk on on roof rakes of much pitch at all...it was not long before they started putting a texture on one side...

 

[MH8675309]

Paint edges and all - I've seen it last ten years and still have nail holding ability

 

[BKBrown]

If it can dry out and the paint is good, it will last a long time. If it stays wet, or the paint holds water, it will swell and begin to fall apart.

 

[deerseeker001]

I have to agree with Gary the Marine plywood is the way to go.

At about 15 to 30 bucks a gallon for paint, it doesn't take much to make up the price difference to a marine grade of plywood that will last years and years without any paint. I never liked OSB as I always found that small pieces always de-laminate and turn into large splinters ready to injure you.

 

[s219]

I've seen OSB scrap get ruined by rain in a few weeks. On the other hand, I have had regular old 15/32" plywood side boards on my trailer for 7 years now. It turned gray, but is still holding up OK and functioning fine. It was scrap, so I figured no big deal if it only lasted a little while, but it's far exceeded my expectations.

By the time you paint/treat OSB, you may as well have gone with plywood to save time/money.

 

[dclynch]

I build all my sheds with OSB. I pait both sides and I currently have one going on 8 years with no signs of needing to be replaced.

 

[like2wheel]

"I bought some on a humid day, & by the time I got home all that was left was sawdust in the back of the truck"
:laughing:

Seriously, for vertical surfaces, it'll be fine. Paint or use a penetrating stain/sealer.

If you overbuild it, you're sure to find a better hunting place next year...

 

[Oliver1655]

My vote is for marine plywood. Not to be confused with treated plywood.

Another possibility would be to use steel/tin. I have re-used old tin on vertical surfaces rarely have noticed a leaking problem.

 

[newbury]

At about 15 to 30 bucks a gallon for paint, it doesn't take much to make up the price difference to a marine grade of plywood that will last years and years without any paint. I never liked OSB as I always found that small pieces always de-laminate and turn into large splinters ready to injure you.

Home Depot - Marine plywood 3/4" $70 ON THEIR WEB SITE
OSB - $15

BUT TRY TO FIND MARINE PLYWOOD!!

I wanted to use marine plywood for building some boxes that I plan to use to haul stuff for decades. In Northern Virginia NONE of the regular lumber yards OR the HD's or Lowes would order it. And I called several marinas. I found one "specialty" shop, referred by a marina, that sold it - $110/sheet! And that was if I ordered 5 sheets.

I have to agree with Gary the Marine plywood is the way to go.

IF you can find it!

I've seen OSB scrap get ruined by rain in a few weeks. On the other hand, I have had regular old 15/32" plywood side boards on my trailer for 7 years now. It turned gray, but is still holding up OK and functioning fine. It was scrap, so I figured no big deal if it only lasted a little while, but it's far exceeded my expectations.

By the time you paint/treat OSB, you may as well have gone with plywood to save time/money.

PT plywood will last for years with a little paint.


I've built a lot of stuff with PT plywood that lived outside with minimal protection, 2 layers of WHOOPS paint, seal the edges, lasts for years. I tried OSB with the same treatment. But with OSB if you get a break in the paint ANYWHERE it just sucks in moisture and delaminates. Nail, screw holes are the worst. With a little normal flexing you get a hole.

I'd say use marine plywood IF you can get it at a reasonable price. PT with a little maintenance is good, OSB requires a lot more careful maintenance.

Now if ANYBODY knows where I can get a good marine plywood near Alexandria Va. for <$70/sheet of 3/4" x 4' x 8' I'd like to know.

Until then I'm stuck with PT at ~$40/sheet.

* WHOOPS paint is the stuff you find at the hardware store for $3 to $5/gallon because someone returned a tinted can

 

[Walkin Horse]

Have you tried Plywood and Plastic in Richmond. I know it's not near you but close.

 

[dave1949]

A frame made of pressure treated lumber covered with roofing/siding metal might be an alternative to wood sheathing of any kind.

 

[BKBrown]

Now if ANYBODY knows where I can get a good marine plywood near Alexandria Va. for <$70/sheet of 3/4" x 4' x 8' I'd like to know.

Right now - 3/4" 4'x8' PT is $51.19 at MWP Supply in Madison, VA - it is a ways from Alexandria, but if you have a trailer to haul it with --- https://store.mwpsupply.com/departments/plywood-treated-untreated-|PW|PLY|PWPLY.html?top=0
and MWP treats their own Plywood here in Madison.

Give them a call and they may be able to get Marine Plywood for you.

 

[newbury]

Right now - 3/4" 4'x8' PT is $51.19 at MWP Supply in Madison, VA - it is a ways from Alexandria, but if you have a trailer to haul it with --- https://store.mwpsupply.com/departments/plywood-treated-untreated-|PW|PLY|PWPLY.html?top=0
and MWP treats their own Plywood here in Madison.

Give them a call and they may be able to get Marine Plywood for you.

Thanks
BUT
That's about 170 miles round trip for me when I'm in Virginia.
I only need three to five sheets
They DON'T list marine plywood https://store.mwpsupply.com/departments/plywood-treated-untreated-%7CPW%7CPLY%7CPWPLY.html?top=0
The $51/sheet PT is about $10, 25% more than what I paid from the local to me in Virginia lumber company and $20 more than what I pay down in Fulton, MS, where I'm at now (I just called - they didn't carry marine plywood either).

I still think the best bang for the $ is PT plywood with WHOOPS paint.

 

[rd_macgregor]

Are engineered wood siding panels (like those often used on backyard sheds) more expensive than marine plywood?

 

[newbury]

Which brings up another possibility.
Concrete. Hardiboard type panels. I built a shed on a 2x4 stick frame. Stuff lasts forever if you don't break it. No paint needed, but I installed it by drilling screws in.