Small Cabin

Small Cabin Forum
 - Forums - Register/Sign Up - Reply - Search - Statistics -

Small Cabin Forum / Cabin Construction / OSB!
Author Message
travellerw
Member
# Posted: 21 Apr 2022 14:20
Reply 


I'm guessing this will be a post with lots of opinions.. but I wanted to hear everyone's thoughts.

In the past I have seen some negative comments about OSB. A couple of posts even suggested that just a few weeks exposed to the weather would make it swell and be useless.

Well.. I left a bunch of scraps and even a full sheet out over winter. Many of the scraps buried under 4 ft of snow that melted on top of them. After a whole winter of exposure I cannot tell the difference from a brand new sheet I bought over the weekend (and damn did that price hurt!). There is no swelling, even at the edges. There was no colour change. Nothing, they look like brand new.

Further to that.. When I mentioned it to my father and said I was surprised based on comments I heard, he just laughed. He took me over to a storage shed on his property and showed me 4 sheets he has had leaned against it for 22 YEARS. While the edges are swollen about 5 inches all the way around, the centre of the sheets looks great. Of course the outer one turned grey, but the others are still brown. If you cut the outer edges off, then you could still use part of that sheet. Pretty amazing for being left in Alberta weather for 22 years.

So I thought I would post and see what other experience has been. For me, I pretty convinced that OSB is no where near as fragile as some believe.. Hell the house builders around here leave it exposed for upto 6 months before they button up those new houses.

gcrank1
Member
# Posted: 21 Apr 2022 18:45 - Edited by: gcrank1
Reply 


My 10x10' tool shed was 'sided' with 7/16th"? at the old cabin. Sometime in the first year I painted it with an exterior dark green (not name brand), no primer, just brushed it on. 30+ years later it was doing very well. A few outer chips had peeled back/broke off but not many. Should have touched those up but lost the place in the estate sale anyway.....
Id use it again.

Princelake
Member
# Posted: 21 Apr 2022 19:08
Reply 


It all depends how they are stored. If you have them laying flat for rain and water to sit on them and soak up the water they’ll barely last a year. Vertically in the sun for water to shed off them and dry yes they’ll last for many years but discolour.

travellerw
Member
# Posted: 21 Apr 2022 22:09 - Edited by: travellerw
Reply 


Quoting: Princelake
f you have them laying flat for rain and water to sit on them and soak up the water they’ll barely last a year.


I had multiple pieces laying flat on the topsoil (not even grass as I tilled that up). They sat like that through TONS of rain and 4 feet of snow over winter. One was even sitting in a frozen puddle of water last weekend.. I couldn't tell any difference from a new sheet other than mud on the soil facing side.

I know they have been working on the resin formulation since some chemicals were banned (at least up here). Maybe the new stuff is much more water resistant then the older formaldehyde based resin!

The reason I brought this post up was because lots of people stress about getting a building buttoned up quickly. I know I was worried about the materials. However, now I personally think its not bad as people think and you have MUCH more time than you think.

paulz
Member
# Posted: 21 Apr 2022 23:01
Reply 


I was also thinking advances in OSB tech maybe. My cabin is sheathed in OSB, going on a decade ago now. No issues other than odor. I stayed in it for several years with no insulation or interior finish (I do miss using the blocking for shelves..) and it really smelled.

spencerin
Member
# Posted: 21 Apr 2022 23:44
Reply 


I once had OSB subflooring down that was exposed.to rain for a month or so. It swelled around the screw holes, and probably would've swelled a lot more had it been exposed longer.

Link44
Member
# Posted: 22 Apr 2022 00:04
Reply 


When my house was built it rained so much before I had a roof that I had 2x4's floating in my to be living room. The contractor said it would be fine. Well 5 years later and the dog can make the floor squeak.

lburners
Member
# Posted: 22 Apr 2022 08:14
Reply 


I have heard some pretty good reviews of the advantech stuff which I believe has some coating allowing them to guarantee exposure for like six months without degradation.
I went with standard ply. With the crazy prices I think the pricing was negligible.

happilyretired
Member
# Posted: 22 Apr 2022 11:10
Reply 


OSB gets a bad rap from some people. It can handle water and dampness a lot better than plywood that easily delaminates.

Aklogcabin
Member
# Posted: 22 Apr 2022 11:26
Reply 


I would disgaree that osb stands up to the weather as good as standard grade cdx plywood.
The current costs are 55 bucks for plywood n 57 bucks for osb here. So no money savings. I've been researching the clod weather climate centers site. They specialize in building. They recommend against using obs and only use plywood.
I have used a lot of each product and my experience has been plywood is stronger.

happilyretired
Member
# Posted: 22 Apr 2022 12:03
Reply 


Quoting: Link44
When my house was built it rained so much before I had a roof that I had 2x4's floating in my to be living room. The contractor said it would be fine. Well 5 years later and the dog can make the floor squeak.

Was the floor glued and screwed? Did they use T&G sheathing?

travellerw
Member
# Posted: 22 Apr 2022 12:58
Reply 


Quoting: Aklogcabin
I have used a lot of each product and my experience has been plywood is stronger.


Its interesting you say that as I can find no data that shows that. I have looked at lots of 3rd party testing of both products and it shows they perform almost identical except in shear strength. Fastener tear through, span width even weather exposure all rate the same in most tests. However, OSB is almost 2 times stronger in shear than plywood.

That would seem to make sense as I-Beam joists are made with OSB and "Lambeams" are pretty much just really thick OSB.

ICC
Member
# Posted: 22 Apr 2022 14:32
Reply 


Decades of experience of building with my brothers company have taught us that OSB has gotten better and much of the plywood has not improved. Rather, we had more problems with plywood delaminations than any issues with OSB, to the point where we rarely used plywood for any purpose that could be done with OSB. As was stated OSB is vastly superior for shear strength, something not enough DIY'ers give enough thought to. We do like Advantech for sub-flooring. It does stand up to wet conditions for months. Newer materials are not always better than older materials or methods but I do believe todays OSB is superior to plywood for general construction.

gcrank1
Member
# Posted: 22 Apr 2022 15:09
Reply 


This is a good and timely thread with building season, or in my case re-building season, upon us.
I have to say the 1/2" OSB I looked at here was flatter and 'straighter' than the shoddy looking 1/2" plywood. After having cut some CDX down in the past and finding what I think are substantial voids between the outer lams, and having driven nail through that didnt feel like they had much resistance, I am not confident in the product.
Then last year when prices spiked I did not rush out to buy some 'before they went higher'. So here I am today thinking ahead, this year may be 'now or never'.

Link44
Member
# Posted: 25 Apr 2022 22:03
Reply 


Quoting: happilyretired
Was the floor glued and screwed? Did they use T&G sheathing?

The floor was glued, screwed and T&G. In the first year the contractor fixed several squeaks with some extra nails. In the last couple years we now have squeaks everywhere.
No one is sneaking up on me in my house!

ICC
Member
# Posted: 25 Apr 2022 22:42
Reply 


Sounds like the bead of adhesive might have been allowed to skin over before the sheet was laid and screwed down. The skin that forms when left exposed to air too long prevents the sheathing panel from adhering to the adhesive. Or the wood was too moist. That is too bad. What type of flooring is used over the subflooring?

Link44
Member
# Posted: 25 Apr 2022 22:53
Reply 


We have some click and snap flooring and some carpet.

ICC
Member
# Posted: 25 Apr 2022 23:24
Reply 


For carpeted floors that squeak there are some special screws that are made to be screwed through the carpet, through the subflooring and into a joist. Once snugged down tight they snap off. I never used any myself but a friend has used them to cure some creaking floors. Sorry but the name totally escapes me.

Link44
Member
# Posted: 25 Apr 2022 23:55
Reply 


Thanks for the tip, I'll look into that.

travellerw
Member
# Posted: 26 Apr 2022 09:49
Reply 


Actually due to the skinning problem with Poly based glues, many quality builders have stopped using them. They instead use the new foam based adhesives (Greatstuff Pro or DAP SmartBond). I used Greatstuff Pro to build my stairs and I can say its crazy strong bond. Of course that is just my anecdotal evidence of glueing 2 pieces together and seeing if I can break them apart. There are tons of Youtube videos with more "scientific" methods.

Further to this.. We just extended our loft and that necessitated us upgrading the joists. I was quite disappointed when I pulled the old joists out how easy it was to break the PL400 bond. It broke everywhere without damaging the OSB or old joist.

If I was to build again, I would definitely use foam based adhesives everywhere.

gcrank1
Member
# Posted: 26 Apr 2022 10:31
Reply 


The PL400 I used in a remodel project was greatly disappointing

travellerw
Member
# Posted: 26 Apr 2022 11:18
Reply 


Quoting: gcrank1
The PL400 I used in a remodel project was greatly disappointing


I found this video very eye opening about PL400. It lost out to every other glue, including hot glue...

https://www.youtube.com/watch?v=xUCB4dhvVlc

Your reply
Bold Style  Italic Style  Underlined Style  Thumbnail Image Link  Large Image Link  URL Link           :) ;) :-( :confused: More smilies...

» Username  » Password 
Only registered users can post here. Please enter your login/password details before posting a message, or register here first.