Another weekend has finally arrived... back to work on coop

[Panhandler80]

I don't know what you are comparing OSB prices to, but here is what I have to pay locally for 4X8 siding boards:

7/16" OSB is $10.36
1/2" Plywood is $26.99
LP SmartSide is $35.99

So, where I live, OSB is by far the least expensive option if you have to buy siding boards. But, I am curious if you have found a less expensive option than OSB for siding because I plan on building another shed this summer and would like to know if I could get siding boards for less money. Thanks.

Yeah, so I'm not sure what I meant by that post. Looks like some fat fingers on the cell phone to me. Same thing here, and I imagine everywhere.

 

[gtaus]

Yeah, so I'm not sure what I meant by that post. Looks like some fat fingers on the cell phone to me. Same thing here, and I imagine everywhere.

Too bad. I was hoping you had a line on something less expensive. Anyway, the least expensive siding board I can find where I live is 7/16 inch OSB.

 

[ColoradoPip]

Doesn't OSB absorb water particles, even through the air? I thought it was a big no for roofing but then see videos and recommendations to use it.

**Edit: Since no one else has replied yet I'll just edit this post. Did some reading on the topic and came across this which I thought was the best description (with a link to a doctoral dissertation on the topic!). It seems like in low humidity areas it's a great material, but in high humidity I would not use it. Interesting stuff!!

https://www.energyvanguard.com/blog/76574/Moisture-and-the-Quirkiness-of-OSB
Sorry for the side topic panhandler, you already have plywood anyways

 

[gtaus]

Doesn't OSB absorb water particles, even through the air? I thought it was a big no for roofing but then see videos and recommendations to use it.

According to the guys at the "Pro Desk" at our local big box lumber stores, OSB is supposed to be actually better than plywood when it comes to not falling apart with high humidity and/or getting wet. They told me that is has something to do with the adhesive used in the OSB which is better than the adhesive in the plywood. I really don't know. But since OSB is cheaper than plywood, and they tell me it's better for what I was building, it was a no brainer for me to go with OSB.

Having said that, the OSB on the siding of the coop is vertical, and therefore there should never be any standing water on it to absorb. Also, I primed and painted the OSB and that should also protect the wood. I also used OSB on the roof, but that is covered with felt paper and then the asphalt shingles. Again, in theory, the underlining OSB should never get wet.

I should also mention that we have a huge OSB particle board manufacturing plant about 20 miles down the road. So our "Pro Desk" guys mostly have lots of knowledge of the products coming out of that plant.

I always thought plywood was better than OSB, but I am told that the OSB today is the better building material in both cost and performance, at least for what I was building.

 

[Panhandler80]

Doesn't OSB absorb water particles, even through the air? I thought it was a big no for roofing but then see videos and recommendations to use it.

**Edit: Since no one else has replied yet I'll just edit this post. Did some reading on the topic and came across this which I thought was the best description (with a link to a doctoral dissertation on the topic!). It seems like in low humidity areas it's a great material, but in high humidity I would not use it. Interesting stuff!!

https://www.energyvanguard.com/blog/76574/Moisture-and-the-Quirkiness-of-OSB
Sorry for the side topic panhandler, you already have plywood anyways

No sweat! Good read.

 

[K0k0shka]

I used OSB on my coop, too, for everything - walls, floor, roof. Mostly because of the cost, but also because I, too, read a lot of encouraging things about it being better nowadays than it used to be, and doing well in high humidity because of the glue they use. The weak point of OSB is the edges. They are sort of sealed when sold, but any new cuts you make expose fresh edges that absorb water way more easily than the pressed flat surfaces. So you have to make sure to seal and protect the edges really well. I painted every surface of my coop with waterproofing stain sealer, and put felt + shingles on the roof. It has gone through its first cycle of summer/fall/winter and so far has held up just fine.

 

[perkolator]

^this. In my experience, OSB's weakness is definitely the cut edges. Holds up surprisingly well even untreated, I've got two potting tables that are at least 10yrs old with OSB tops - sat 8yrs half-protected under an awning but three years out in the full elements and they're still in decent shape; with paint/coating they'd hold up even better.

We use a lot of 3/4" AC-grade plywood in ceramics studio and everything gets exposed to moisture - it does hold up if you take care of it, but once you start getting it wet it tends to want to delaminate, the adhesive just doesn't hold. I used OSB on my coop.

 

[Panhandler80]

^this. In my experience, OSB's weakness is definitely the cut edges. Holds up surprisingly well even untreated, I've got two potting tables that are at least 10yrs old with OSB tops - sat 8yrs half-protected under an awning but three years out in the full elements and they're still in decent shape; with paint/coating they'd hold up even better.

We use a lot of 3/4" AC-grade plywood in ceramics studio and everything gets exposed to moisture - it does hold up if you take care of it, but once you start getting it wet it tends to want to delaminate, the adhesive just doesn't hold. I used OSB on my coop.

I'm a little irritated that I didn't use treated trusses and outer bands for roof. Oh well. Putting peel and stick underlayment on plywood and then metal roof. Plywood overhang trusses a bit and metal overhang ply, so trusses should never see actual water, but will be exposed to humidity. But that's just like every stud in walls, so....

 

[ColoradoPip]

Are you painting or staining the exterior? If so, you could apply it to the rafters, or at least the overhanging portion.

 

[perkolator]

I'm a little irritated that I didn't use treated trusses and outer bands for roof. Oh well. Putting peel and stick underlayment on plywood and then metal roof. Plywood overhang trusses a bit and metal overhang ply, so trusses should never see actual water, but will be exposed to humidity. But that's just like every stud in walls, so....

I think it will be fine....can always rebuilt it later if it isn't
I simply went with rafters, a few purlins and metal roof directly to those, no plywood...but I don't have hurricanes to worry about