When you talk about using cob for the interior plaster, be careful. As I mentioned in my last comment, you want to stop moisture from getting in but make sure it can get out if and when it DOES get in. If you have a highly permeable interior (clay plaster) and a low permeability barrier on the exterior (plywood) you run the risk of moisture build up in your walls. Cooking, showering, breathing, plants...they all create moisture in the interior that will be pushed through the walls as it escapes.
I always try to have less permeability on the inside than the outside. That way, if something does make it into the wall, it will have an easier time getting out than it does getting in.
The plywood will likely act as a vapor barrier, thus trapping moisture between the exterior face of the bales (or in this case the loose stuffing) and the back side of the plywood. Also, the loose stuffing give a place for rodents to get in where as a properly constructed bale wall, with plaster on both sides and no stud spacing, will not provide that bedding area.
Yes,it is possible that the plywood may act as a vapor barrier.
What I can offer is that when it is 0F outside, then any moisture in the bales will freeze before it ever gets to the plywood, and that heh [plywood will have no impact on the latter process.
The real problem now is how to keep the moisture from ever getting in to the bales in the first place. Like with a polyurethane barrier ON THE INSIDE under the interior stucco.
This is a common mistake with conventional construction... putting the barrier on the outside as a wind break instead of addressing the barrier issue at the inside. Think thermos bottle in an insulated wrap.
With respect to the loose straw, it has nothing to do with rodents getting access. They will have their access regardless of loose straw or not. They will take up residence in all of the bale junctions anyway.
I have plywood on outside and floor. I have sheet rock on top. I have stucco on the interior. So far, the mice have preferred the kitchen drawers over the straw bales for nesting. And that was easily fixed once I figured out how they were getting in.
My problem now is that I have recently learned from some natural building , specialists that the cement in the stucco is a bad plan. So now it looks like a cob plaster for the inside is in order.
When you talk about using cob for the interior plaster, be careful. As I mentioned in my last comment, you want to stop moisture from getting in but make sure it can get out if and when it DOES get in. If you have a highly permeable interior (clay plaster) and a low permeability barrier on the exterior (plywood) you run the risk of moisture build up in your walls. Cooking, showering, breathing, plants...they all create moisture in the interior that will be pushed through the walls as it escapes.
strawbaleinnovations 1 year ago
I always try to have less permeability on the inside than the outside. That way, if something does make it into the wall, it will have an easier time getting out than it does getting in.
strawbaleinnovations 1 year ago
The plywood will likely act as a vapor barrier, thus trapping moisture between the exterior face of the bales (or in this case the loose stuffing) and the back side of the plywood. Also, the loose stuffing give a place for rodents to get in where as a properly constructed bale wall, with plaster on both sides and no stud spacing, will not provide that bedding area.
strawbaleinnovations 1 year ago
Thanks for the input. It is appreciated.
Yes,it is possible that the plywood may act as a vapor barrier.
What I can offer is that when it is 0F outside, then any moisture in the bales will freeze before it ever gets to the plywood, and that heh [plywood will have no impact on the latter process.
The real problem now is how to keep the moisture from ever getting in to the bales in the first place. Like with a polyurethane barrier ON THE INSIDE under the interior stucco.
wa7mlh 1 year ago
This is a common mistake with conventional construction... putting the barrier on the outside as a wind break instead of addressing the barrier issue at the inside. Think thermos bottle in an insulated wrap.
With respect to the loose straw, it has nothing to do with rodents getting access. They will have their access regardless of loose straw or not. They will take up residence in all of the bale junctions anyway.
wa7mlh 1 year ago
I have plywood on outside and floor. I have sheet rock on top. I have stucco on the interior. So far, the mice have preferred the kitchen drawers over the straw bales for nesting. And that was easily fixed once I figured out how they were getting in.
My problem now is that I have recently learned from some natural building , specialists that the cement in the stucco is a bad plan. So now it looks like a cob plaster for the inside is in order.
wa7mlh 1 year ago