Advantech sheething with Tyvec rain screen?
green654
| Posted in General Questions on
We are building a new house and I’m concerned about mold and avoiding problems within the walls down the road. The exterior will be hardie board. We are going with Advantech sheething with Tyvec rain screen over it. Is this sufficient? My understanding is that Advantech is moisture resistant and the rain screen over it provides an additional layer of protection from moisture. Thoughts?
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You are installing Huber Zip panels, correct? If so, you want to follow the manufacturer's installation process to preserve your warranty.
ZIP has a integrated water resistant barrier, but it has to be taped. I would look at all door and window opening to ensure that they are being properly prepped. I would also consider installing a rain screen so the sheathing and siding can dry more easily.
I spoke to our builder. He said he can’t put in a traditional rain screen with furring because the siding won’t lay flat with this type of system. So he’s putting in Tyvec drain screen over the Advantech zip sheething. This ok to do?
That information is not accurate. James Hardie has installation documents showing this exact assembly detail. You may provide this references to ease them into the idea.
https://www.jameshardiepros.com/getattachment/ea6d46d8-9002-4a08-ba22-ba40a9dfbe9f/14816-0eb5542a18f959b
https://www.jameshardiepros.com/getattachment/ea6d46d8-9002-4a08-ba22-ba40a9dfbe9f/14816-0eb5542a18f959b
Do you mean Tyvek Drainscreen? If so, that looks like a good option to me. Maybe Mike will comment on it as well.
Steve,
If you're talking about Tyvek stuccowrap, or drainwrap, then yes. Those are explicitly listed in the pdfs listed above. If you're talking above drainvent, I'm not sure. That looks like it has to be backed by another layer of WRB. I'm not sure what zone we're talking about, but if it's not in New Orleans or close by, either of the two listed wraps should fulfill the requirements.
Huber makes both Advantech sheathing and Zip system sheathing. As Steve says, the Zip system is water-resistant. It's a good system but to sleep better at night I still include an inexpensive WRB over it.
If you really mean Advantech, their floor sheathing has a lot of paraffin in it which makes it water-resistant. But you probably mean their wall and roof sheathing, which does not have as much paraffin and is only a little better than competitive OSB products and it definitely needs a separate WRB.
Make sure that the wall complies with the recommendations in Table 2 A or B here.
So I spoke with the builder. To be exact, we have Advantech Zip sheething with Tyvec drain wrap over it with a perm rating of 50. So now the question is….. should I put furring strips on top of the drain wrap before the Hardie Board cladding to create an air gap for a rain screen OR should I just put Hardie board directly on top the drain wrap?
Where are you located? There are a few locations where rainscreens (or as building scientist Dr. John Straube calls them, drainage and ventilation gaps) are not recommended, but in most places they are a good idea. Martin covers the topic here: https://www.greenbuildingadvisor.com/article/all-about-rainscreens. Including an air gap of at least 3/8" is better than only having a bit of space (as with Tyvek Drainwrap) that allows water to drain. But that's better than nothing.
Huber makes Advantech and they make Zip sheathing. There is no such thing as Advantech Zip sheathing. I assume he means Zip sheathing.
I think everyone will advise you that an air gap is better. The Tyvek over the ZIP is a belts and suspenders approach, which is fine. But regular Tyvek house wrap (or even Commercial D) isn't a substitute for an air gap. And again, all the seams need to be taped and all openings need to be prepped before windows and doors go in. Otherwise, why waste money on using ZIP.
You can use strips of 3/8 plywood for strapping. It doesn't have to be pressure treated based on what I've read.
Thank you!!!