I was going to post this on the SIPs thread, but figured better to not hijack it.
So my question: Due to a delay in getting my SIPs panels, my OSB decking is left exposed. It will be about 3 weeks of wet and freezing cycles before the SIPs will arrive. Should I be concerned about the decking?
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Replies
<, my OSB decking is left exposed
Should I be concerned about the decking?>
what kinda of osb is it?
Can't you cover it with some visqueen while your waiting
with some boards underneath for ventilation.
And when the sun is shining uncover to let it air out.
If you don't allow for ventilation you could cause mold and
mildew.
And "IF" you can get it dryed ou,t go to the paint store
and get some cheap oops paint and coat the floor
so when the framing begins you can still protect it from
any future moisture problems.
Edited 11/22/2005 8:42 am ET by butch
I didn't know there are different types of OSB for home construction. What is typical for the midwest? I was told by my builder it'd be ok. Not that I don't trust my builder, but conventional wisdon says OSB and water don't mix.
I guess sometimes conventional wisdom is wrong. ;)
This stuff is rated for exposure to weather for normal construction delays. Otherwise, it would be unusable for much of the country. Anything less than a month or so should be OK, assuming the framers spaced the panels properly. he might have to come back and hit the edges with a sander after you're closed in and dried out, but that's no big deal.
Huber AdvantechThat is the only osb I would trust to leave exposedfor any length of time.
I found on my siding that it swells and buckles even after leaving the required 1/8 inch gap. It doesnt go back down after drying either. This is type 1 for exposures.
Keith
Why don't you just put a tarp down until they come?
I never use osb anyway on a deck but I had to start framing a 6000 s/f house once and was pulled off for 3 weeks and I put a tarp down until I came back.
I had some osb that took at least a years worth of weathering. It held up fine. I didn't have to sand it, and it didn't buckle anywhere. It was "regular" osb, not advantech.
I think some parts of the country uses lower quality supplies. Around here, I've never heard anyone complain about any osb products on wall, roofs or floors. I do remember in my early apprentice years of hearing a lot of stories about buckled roof plywood, especially yellow pine cdx.
blue
I assume by 'decking' you are talking about the subfloor. In that case, you could paint it with a couple of coats of OOPS paint, preferably a high-gloss finish, and then after the first rain, come back and drill drainage holes in the center of any low spots that accumulate and hold standing water. I have seen painted OSB used as exterior sheathing on sheds last for quite a while...but siding doesn't have to resist pooled water. Big difference....
Another idea you should consider is framing a quickie pitched 'roof' out of 1x right on the floor and then drape good tarps over that so it will shed water. This might sound like a big deal, but actually it could take less time than putting two coats of paint on the floor. Make sure the 'eaves' overhang the floor deck so that run off hits the ground and doesn't drool back under the tarps on to the subfloor. A 3:12 pitch would be more than adequate.
Dinosaur
Hold your ground!
I see in your eyes the same fear that would take the heart of me....
A day may come when the courage of men fails,when we forsake our friends and break all bonds of fellowship...
But it is not this day.
an alternative to paint could be a water sealer, such as Thomspons, it's not to expensive. We've used it in the past over either 3/4 ply or advantech if we knew it was going to be exposed for a while. our overly technical application method involved a poor and mop technique.
or you could go balls out like one customer of ours.... The started building a house about 3 years ago, left at the first floor deck, covered the whole thing with an EPDM cover that probably cost about 3 grand....
I dunno about that Thompsons stuff on standard OSB; seems to me OSB could drink up a good bit of that. OTOH, there is a grade of OSB I have sometimes used for roof sheathing in outbuildings which has a fairly high-gloss sheen to one side (slippery as he!!, too) which might not be so much of a sponge if used that side up (the other side is textured so the carps don't have to wear ice crampons to survive up there...).
I still think the best solution for this situation is to build up some sort of sloped support for a tarp. Even a pile of 2x6 in the center of the floor as a sort of ridge might be enough if they stretch the tarp or poly sheeting nice and tight and tack it to the rim joists below floor level.
Dinosaur
Hold your ground!
I see in your eyes the same fear that would take the heart of me....
A day may come when the courage of men fails,when we forsake our friends and break all bonds of fellowship...
But it is not this day.
Local HfH chapter applies Thompsons immediately after OSB decking is installed, ceased to have any buckling problems after adopting this as policy. Sometimes these homes are open for a long time, the lousier the weather, the longer they are open.
OSB will soak it up like a sponge, BUT, you do not have to apply it to the point of refusal to get the benefits. We use 4 gallons on 24x36 ( ~216 sqft / gal ). Pay special attention to any cut edges. Bore drain holes at low spots after first rain to avoid puddling.
Roll it out about as thin as you can get it - slop and mop technique will use considerably more. Other than a slight darkening of the OSB, you would never know it was there. Seems to harden the surface slightly and helps to resist months of foot traffic.
Thompsons ceases to off gas after 21 days according to the factory tech reps so any noxious fumes will be long gone before the building is sealed up.
Never have put any onto roof decking as felt goes on pretty fast.
Just my experience and observations.
Jim
Never underestimate the value of a sharp pencil or good light.
Right... but a better use of time and probably equal money would be to just by Advantec to start with.
As far as the performance of Thompsons and your statement that it stops off-gassing after 21 days, well yea, I'll buy that too, but only knowing that Thompsons is a good temporary protectant and knowing that it is 80% to 90% thinner, urine would probably work nearly as well provided it contained an appropriate amount of hops :-)
Bit late to use Advantech - deck is down and SIP's are delayed - see post 1.
As for the performance of Thompson's on OSB - like I said, just my personal observations.
Jim
Never inderestimate the value of a sharp pencil or good light.
"Bit late to use Advantech " so true - but I was referring to the HfH homes you are building. Going forward, they do have the option to use floor sheathing that is a bit more durable, as opposed to slapping a Band-Aid on every house built.
I thinjk either the Thompsons or the Ooops paint would do fine here. The diff being where CAG thought the Thompsons would be cheaper.it would be conpared to normal paint on the shelf, but gallons of mistakenly mixed paints can be had for about 2-3 dollars
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Didn't think of it that way, our paint store usually doesn't have much "oops" paint on hand, though I do see it quite frequently at HD..
My current project is at this stage and will wait until early spring for exterior framing (probably SIPs panels).
I watersealed the OSB (2 coats) and then covered it with visqueen for the winter. I also drilled the subfloor where puddles were sitting for drainage.
Problem that i ran into is the wind. The day I started laying out the plastic, very calm and of course as soon as I had it unfolded the wind came up and blew for the rest of the day. I ended up spreading 2x4s, full sheets of 3/4 OSB all over the plastic since it kept parachuting up and whipping like crazy. I probably should have folded up and tried another day, but I was already committed. After I had things bak under control I tacked the edges over good. Well the darn wind kept parachuting the plastic and lifting the OSB, etc. until it would slide right off the subfloor. I then had to run around and nail the wood down through the plastic to the subfloor. Of course this compromised the water shield.
The next day I went out to check on how well it held up to the wind and found the 2x4s/nails had been pulled out by the wind. So I ended up using screws to hold them down to the subfloor.
Well in the early fall. the rains did drip through quite a bit into the basement (which I have left the walkout door off for ventilation) but now that winter has arrived and temps are freezing the dripping has stopped.
I have noticed little to no buckling or uplift from the OSB getting wet. I will jsut keep an eye on it for snow removal if necessary, but the TJI guy said it should hold several feet of snow before I should get worried.
I said that shouldn't be a problem as I'm sure the wind will blow if off long before the depth becomes an issue.
I plan on pouring 1.5" gypcrete (or similar) on top of the subfloor for radiant floor so the cosmetic look of the OSB is of little concern. I've talked to everyone around here and no one seems to think it should be a problem. Of course, Idaho is pretty dry compared to Oregon or South.
I would definately prep it somehow as suggested above rather than leave it raw and you should be fine. Good Luck!
There's only two ways I can think of to deal with that. One is to tent the tarp to shed and nail it all tight. Plastice will never last out the winter.The other is to use I&W shield over all
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BTW - I was reading an article in JLC about soy based adhesives that are being tested as a replacement of the formaldehyde based glue currently used in plywood and OSB. Preliminary results show superior adhesion and durability in wet conditions and much less environmental impact both at the factory and in the home with a potential for less production expense. The production expense savings comes in the form of not needing to burn off excess factory chemicals, although the article really doesn't address the cost of the soy based glue in the first place... Sounds pretty significant to me though... Maybe not good news for Huber/Advantec though. I guess really though, it will take years to tell if the material produced will have true longevity... I remember the fire retardant plywood of the '70s... :-(
> gallons of mistakenly mixed paints can be had for about 2-3 dollars
You're getting a good deal there. Out here, the Oops paint is more like $5-7/gal.
-- J.S.
2 to 3 is what happens after you ask 'em what they got to have for the whole collection.
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I can't believe people are talking about sealing plywood decks. What kind of crap are you using that you have to seal a plywood deck on a house that is being framed even if it's exposed for three weeks?????The answer to the original posters question is so simple and it's being so blown out of proportion I can't believe what I'm reading....Put a tarp on the deck for three weeks and that's it. There's no walls on yet. What is the big deal people?????????From where I'm from we frame house that take 4-6 weeks to frame and we have ice skating rinks on the decks and then they thaw out and we finish the house and that's it. What kind of crap are you guys using that you need to seal a plywood deck ?????? Your not building and finishing furniture...........Joe Carola
I use Huber Advantech so as not to worry, but I can't imagine being able to sdo anything constructive witha tarp. It would be 1.5" deep in water and I've never yet seen a tarp that will hold it all out so it would just KEEP the deck wet and make things worse
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"I use Huber Advantech so as not to worry, but I can't imagine being able to sdo anything constructive witha tarp. It would be 1.5" deep in water and I've never yet seen a tarp that will hold it all out so it would just KEEP the deck wet and make things worse"Piffin,Not of you put them down right. Dinosaur already said the right thing twice and nobody listened to him either. Raise it up in the middle which is common sense. Put a 2x12 on edge and run 2x4's perpendicular to the 2x and create a small roof so the water sheds off. It's that simple. Or if you’re not happy with a 2x12, frame a temporary wall about 3' high and do the same thing with the 2x4's.I've tarped a ton of houses that I do add-a-levels on this way with tons of rain coming down and never had a problem. You have to know how to tarp right.If the deck did get 1.5" of water on it, why would it make the deck worse? What kind on crap are people using? Like I said above I've framed house that sometimes take 4-6 weeks to frame and the decks have a sheet of ice on them like an ice skating rink and sometimes the deck has 1 foot of snow on it. It's hard to protect a deck when all your walls are up and then you get rain or snow. If you’re framing a 6000 s/f house, it's hard to tarp. If you framing an add-a-level you HAVE to tarp, no questions asked and you learn how to properly tarp.Sorry Piffin, I didn't read your post #26.Joe Carola
Edited 11/24/2005 6:27 am ET by Framer
It was when you used the phrase to lay down a tarp that I thought you meant direct on without tenting. We're all on the same page now. I had agree with Dino's comments way back earlier.
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Since he didn't use Advantech from the sounds of it, that is the only right answer now.
Welcome to the Taunton University of Knowledge FHB Campus at Breaktime. where ... Excellence is its own reward!
the standard osb used on the first floor of my sister's home swelled up to a 1/4" at every butt (4') joint after 2 or 3 rains.
the second floor got covered before the rain touched it and it was ok.
imo, the stuff is absolute crap. you get what you pay for. it is still by far the cheapest subfloor material at about $8 less per sheet than fir ply or advantech.
the builder saved his $8 per sheet and it didn't cost him a dime to do anything about all of the humps because he refused to do anything.
the hardwood on the first floor squeaks nicely after only 3 years.
carpenter in transition
Your experiences with OSB are right on par with mine.
Two good rainstorms and the window cuts outs swell to where the builder had the option of extensions jambs or belt sanding the RO's. Same thing with floor seams. 1/4" rise in many spots of properly gapped decking. On the roof, sagging between 24 OC trusses.
Not calling Blue a liar or anything, in fact I think he must be right. Different parts of the country must get different qualities of stock. Around here the OSB is garbage and everyone knows it... and that's not just heresay, we pretty much all have a horror story or two to tell.
You don't even have to go to different parts of the country. up here I can get OSB in poor, poorer, and poorest
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lol
Diesel, just recently I had a load of wall osb that seemed to swell more than I've ever noticed before. It's quite probable that different mills make better than other's materials. Honestly, the house I said got a years worth of water had a mixture of osb, sturdi floor and even a few sheets of a cheaper version of sturdi floor. It took a lot of water and I didn't do any sanding, nor did any plywood bubble, which surprised even me.
I do lay the stuff with gaps on all sides. None of the joints needed sanding. I did have to replace some stuff on the edge under the doorwalls studs where it never dried out.
The osb that I see in the big boxes looks like junk-stuff that I'd never use anywhere for anything but our lumberyards don't ship us stuff like that. We do have fairly stiff competition amongst the yards and if one starts shipping junk, it's easy to find someone that will take the oder and deliver a better product for the same price.
blue
So - the Q that is being posed to you is what OSB brand/product was used?
Either way, I've had cheap OSB exposed for that long and get fairly wet and it worked out OK since most finish floors are going to get some kind of underlayment anyway. If it is that bad, it can be sanded with a floor sander.
Have no idea what the brand being used is, only that the builder said it will inhibit water penetration for the short term.Problem is by the time we found out about the SIPs delay, we were already in the wet and freeze cycle. So I can't paint or apply a tarp now. There is probably a thin layer of ice and snow on top of the OSB.It seems mixed from discussions here what will happen to the OSB. I just hope, from the confidence of the builder, that it is the better brand. Your comment on cheap OSB helps.
If you already have a layer of ice and snow on the floor deck now, forget about it unless it looks like it is going to warm up close to the freezing point. As long as it stays well below freezing, snow is not wet.
But if the weatherman says you're gonna have a thaw, get yer snowshovel going beforehand and shovel off that snow while it's still cold and dry...and light. Warm, wet snow is heavy....
Dinosaur
Hold your ground!
I see in your eyes the same fear that would take the heart of me....
A day may come when the courage of men fails,when we forsake our friends and break all bonds of fellowship...
But it is not this day.
I agree with Framer, put a tarp over it. This time of year, 20's today, you won't be able to paint it and in three weeks you may have a foot of snow sitting on it.
I have shoveled plenty of snow off decks and it is no fun throwing it out window and door openings either, althougth it does warm you up on a cold morning.
My SIP's made with OSB) were exposed to the full wrath of weather from fall rains thru winter storms and spring winds (plus pleanty of rain)..... finally nearly 18 months later The SIP's were under shingles.
I checked with the manufacturer and according to him there were several homes built and exposed to the full brunt of the weather for well over two years without any negative impact.
There is a world of differance between a piece of OSB sitting continously in moisture and normal exposure to rain and sunlite.. Yeh there was some minor swelling on the edges and even a few flakes of wood chipped off. Other than that the OSB held up very well, it never got mushy or soft and held nails as well as a fresh sheet of plywood did..