Just explaining how ridiculous the price
is on ebay and people selling 10’ at a time.
Best scenario: Look for hotels & other commercial bldgs putting up the Tyvek CommercialWrap during construction. Not all of them do, some use HomeWrap, but there’s a substantial difference, both in thickness/durability, and in the amount of waste generated. Home builders try to save every penny they can, but commercial builders don’t care. That’s the good stuff, and larger pieces could be had. Save a bundle doing a little re-con in your own area. . . .
I have used different types & brands…
…of this material as a housewrap, installed as specified, and have experienced water damage on several jobs at different locations. My own house is wrapped with Tyvek and I have had some water damage. In fairness the tape was not yet available when some of these jobs were done. Perhaps that past track record is what Kale was referring to as well.
To the best of my knowledge Tyvek was always advertized as an air infiltration barrier/vapor barrier but not as a guaranteed moisture barrier. They may be making that claim now, but I’ll bet it’s only warranted on vertical walls.
I’ve never seen it used on roofs, even temporarily. In fact, the membranes used by flat roofing contractors have nothing in common with Tyvek. If you stretch out a piece horizontally and pour water on it it will eventually seep through.
Dupont (Tyvek’s manufacturer) makes different formulations, including coarser ones that pass moisture more readily for landscaping applications. I don’t think any of them would be suitable for keeping horizontal surfaces completely dry (but good as breathable car/boat covers).
If any of you are having trouble finding the small amounts you need, I have 3’ & 4-1/2’ rolls of Typar (same stuff, different manufacturer; it’s light gray) I bought at an auction for half price…I can cut whatever lengths you need at my cost; should be cheap to ship.
A little disinformation there.
You’re a little confused. Tyvek doesn’t manufacture anything for the landscape market. They DEVELOPED one here, and do still make it in Europe. However, they sold the US facility and trademark. It’s Typar. Typar IS a landscape fabric that Remay bought from Dupont, slapped a thin film (same thickness as a plastic grocery bag) on it and called it a house wrap. Dupont Europe still makes Typar branded landscape fabric, btw.
You ARE correct in that Tyvek was never meant to hold out puddling water. None of them will. That is why you haven’t and shouldn’t see any house wrap used on roofing as an underlayment.
Where typical water damage occurs is from several places. Reverse flashed windows, lousy brick work with either no 1" air gap, or sloppy mortar up against the wrap causing puddling. I’ve seen reverse-lapping on the wrap as well. All sidings leak, especially brick, when wind-driven rain hits it. The wrap is meant to deflect that water down. Reverse laps and taping jobs that are more common than 2x4 walls allow it INSIDE the wrap, and non-vapor-permeable wraps then hold it in. Tyvek should allow it to dry out, thus it’s considered the best defense because it’s a “forgivable” system.
However, I can guarantee you that in no way, at no time, did Dupont EVER call it a “vapor barrier”. Water barrier, wind barrier, yes. But its desing and benefit is the opposite of a vapor barrier, which is actually closer to most other wraps.
Another place for water damage is in lousy insulation. When 70 degree, warm humid air inside is forced out through the wall system because of pressure on the home from wind or whatever, that warm humid air hits the cold side of your outside wall, cools, and the humidity goes above 70%, the threshold for mold growth. Vapor barriers installed on the inside of the studs were designed to help stop this, however, since they get nailed through, cut out for wiring boxes and punctured by drywall screws, they do nothing but cause problems. They are recommended against nowadays.
BTW, Typar would still make a good ground cloth for a tent. Although, it’s coating is much less durable than Tyvek, and actually one of the worst on the market. It won’t hold out water for half as long as Tyvek once used a few times . . . .
Yak O’ Steel…
I wish more topics were answered the way you answer one. Too many people throwing in an opinion when someone needs an answer. Sometimes they insist it’s correct info when it is, at best, just an opinion and on the water that could be dangerous at times. Thanks!
Yak Man…
…you are indeed a fountain of knowlege.
I have seen the landscape fabric & it does not seem to be the same stuff sans the coating…looks to be a “looser” or coarser weave than the regular (or “housewrap”) Typar. I would suppose it has no coating & is supposed to pass water readily…is that correct?
Also, when used as a housewrap, if the stuff is sided over before it has a chance to deteriorate, why would the durability be a factor? (Remember now, you no longer are employed by the Tyvek folks!)
I am starting to see unbranded housewraps with the builder’s name printed on it.
Misunderstood.
I was talking about the durability as used for a tent covering. Not as a house wrap. You are correct that once a wrap is installed and covered by siding/brick, there should be little or no deterioration past that point. Durability IS an issue though during the installation, and I’ve seen a lot of Typar installed & ready for siding where the coating was damaged all over the place from rough handling during installation. That means the water/air barrier properties in those micro scratches, rips, tears or coating break-down areas is no longer effective. Tyvek will damage too, of course, but it seems stronger. Both Typar’s coating and Tyvek will break down from UV exposure over about 3 months. I’ve seen a lot of that damage as well.
Remay’s Typar manufacturing facility (I was told) is about 300 yards from Tyvek’s, separated by a chain link fence. That’s because Dupont built it and produced the landscape fabric before selling the trademark and facility to Remay. I don’t know that there’s any difference between the weave on the landscape stuff and the weave pre-HW-coating on Typar, but in either case, the weave is simply a tear-strength attribute, not an air/water barrier. The thin film serves that purpose, and IMHO, is worthless since it also holds moisture in and/or is easily damaged.
Now, for the record, the distributor that recruited me away from not only a current job, but also away from another job offer, did so by convincing me how stable they were to work for. Dupont funded 50% of my salary, and when the housing market forecast for 2007 came out in Feb., they pulled the funding, and instead of finding other alternatives for me to do for them, the distributor dumped me w/ no warning, no severance and barely an apology, after just three & a half months from my hire date. 
Although things actually worked out better for me than if they hadn’t hired me at all, because it qualified me to interview for the job I have now, with better salary, better conditions, better company, believe me when I say that my 13 weeks of unemployment left me a little bitter toward Dupont and Monsma, the dist. Although I’m over that, I can’t promise I wouldn’t chuckle a little if they both went belly-up tomorrow. ;~)
I was only correcting you here for the sake of accuracy. I’ll be the first to tell you that Tyvek isn’t a perfect product, nor is it the end all housewrap. But with 50+ other branded products (not counting the builder/lumber yard custom logo stuff) out there, they not only invented it, it’s still the only one that allows a wall to dry out. Like 10x more vapor transmission than anything else, if I remember right. Everything else holds in moisture, and felt/black paper does little for air penetration, or bulk water over time. The biggest problem w/ any housewrap, however, is installation errors. Dupont w/o a doubt has the best recommended procedures on that, as the theme is lapping down, like shingles on a roof. Water runs down, so every seem on tape, windows/doors, flashing, lap joints, etc. should point down like on a roof. If you tape windows, make sure the house wrap from above comes down and laps over the tape. Taping on top of the house wrap will simply fail after a couple of years of getting wet, then the window leaks into the wall. I’ve seen more installation errors than correctly installed stuff, regardless of brand.
What’s really relevant here, are the benefits for using any HW for tent ground cloth, and the bottom line is any of them will be good for that, but none of them will last long before it needs replaced. And it’s way too expensive compared to a plain old tarp, IMHO, unless one is getting scrap for free from a building site. If that’s the case, go for it, roll it instead of folding it for storage, keep it out of sunlight, and find some more scrap when it’s worn.
Thanks.
I get a heck of a lot more info here for myself than I have to pass on about paddling. I’m relatively new, a mere rec-kayaker/kayak fishing kind of guy with no interest in sea kayaking or ww. So there’s not a lot of opportunity for me to pass out much advice. But thanks for the comment.
thank YOU…
…I don’t mind being corrected by someone as knowledgable as you (I have learned a lot from you on other subjects as well) and I admit I was unaware of the relationship between Remay & Tyvek.
My point in both posts, however, was that in the context of this thread, when used as a groundcloth or boat cover, Tyvek is not meant to be waterproof. It may be an effective moisture barrier when properly installed on vertical surfaces, but not when used horizontally.
Actually, one of the “props” I had to
leave behind with builders to show that it was an effective bulk water barrier was a plastic bottle with a 4" wide mouth, kind of like a mason jar. The lid was just a frame, and I’d fill the bottle with water, put a piece of Tyvek over the opening, and screw down the cap. Turn it upside down, no leaks. put a nail through it (although not suggested by Dupont), still no leaks. Then do the same with their brand (whatever they were using) and your hand got wet every time.
Until it would get worn from folding and creasing, it would serve fine for holding out ground water from one’s tent. However, unless it’s free scrap, I still say a cheap tarp is a better buy, and won’t wear out as fast . . . .
But you are right, that it is designed for vertical surfaces. But one of their other products is called AtticWrap, designed to be installed on TOP of the roof joists, then 2x4 studs on top of that to take the decking, and create an airspace between the two for ventilating the deck. Although at an angle, if the roof were to leak, one of the reported advantages is that the water from the leak would run down on top of the wrap and out the eaves, rather than into the finished space. AW is the same material, but with a radiant barrier coating to reflect heat back into the finished space. It’s a green thing . . . .