Does membrain work well for vapor variable air barrier
I was able to locate some membrain and I’m trying to decide if this or intello is better. Intello is much more expensive but I’ve read it’s really nice I just wanted to have a little more protection then doing just an air tight drywall approach. Kinda like an insurance policy. I have r14 outside my walls. R 21 inside so I’m at what code and the 33% rule require. Like I said insurance plus inspector would like to see a smart vapor retarder he know about codes but preferred this option.
Basically wondering if membrain works as advertised I don’t see to many threads about I’ve read about intello and sigas products. I figure if it does the job and at a better price it’s a smart buy but figured I’d ask. Appreciate any thoughts.
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You don't really need anything with your insulation mix in most normal climate zones. It doesn't hurt to have an extra vapor retarder though.
Intello is more durable than MemBrain. I've used MemBrain without any trouble though. MemBrain can tear from punctures if you're not careful, but I've never had a problem. I put up MemBrain with a pneumatic staple gun, some polyurethane sealant, and 3M flashing tape. No problems so far, so for me it's an easy way to save some money compared to Intello.
Bill
Awesome thanks for the info. I notice you answer quite a few of my questions or chime in so thanks a lot for that. My walls are poured and I’m just getting my last little bit of stuff ordered and put in our warehouse.
My background is more finish work cabinetry high end detail work. So I know I can do this well just a little hesitant because I’m new to it.
I’m actually considering after the drywall’s up to try aero seal to make sure it’s real tight.
Thanks again.
I try to answer any questions that pop up in the Q+A that I have knowledge about. Glad you've found some of my answers helpful :-)
If you do a good job of airsealing as you build, you don't really need to use aero seal. Aero seal is EXPENSIVE, and I'm a little hesistant to use it myself for fear that it gets into places it really shouldn't. People have had good experiences with their system though, but I think if you do a good job during your build, you don't really need to go to the extra step of an aeroseal run.
Bill
Membrain is more vapor-open than Intello when dry, and opens up earlier and more than Intello when wet. It's also not as durable as Intello. But with a reasonably safe assembly, as you have, and if you're not also trying to use it as your air control layer, and if you're controlling indoor humidity so it doesn't get above about 50% RH in colder months, I think Membrain would be fine.
Yes I have a hole house dehumidification system plan on it being about 30-35%.
Also it is part of the interior air barrier along with drywall and I’m going to try and use aero seal to keep the inside as tight as possible since I know air transfers more moisture than diffusion.
> dehumidification system plan on it being about 30-35%
Note that typical dehumidification systems won't bring humidity this low. In Winter, you need to use outside air to reduce humidity to such levels.