Betsy Nelson

John C Daley wrote:This may be a good topic to read;
https://permies.com/t/211819/Straw-bale-Eastern-Oklahoma-Hot

As a Civil Engineer, I have to point out a few points;
- slab would normally be thickened under cob walls
- Nothing needs to be under the cob, but it is a good idea to lat a row of fired bricks to create a hard architrave to protect the cob.
- Can you make earth bricks and lay them next to the external walls and then plaster them?
- furniture can be cob

Earth bricks are a great idea!
Yeah, I plan on making the furniture from cob, and then also a large batch RMH stationed in the sun from south facing windows. I'm not sure how much mass is needed for passive solar, I'm just running on the theory that more is better lol

Hi all!
My husband and I are starting to build our home this summer, and after many many rounds of planning, discussion, and compromise I believe we've settled on ICF exterior walls with cob interior walls. We're building in northern MN, so the insulation of ICFs is necessary, but I want as much thermal mass as I can get.

I have two questions- Is there anything special I'd need to do to build interior cob walls on a concrete slab? Can they go directly on the slab with nothing between?
And also, how feasible is it to plaster the inner walls of the ICFs with cob? So instead of insulation facing the inside of the house I'm hoping to coat them with 6 inches or so of cob and gain thermal mass that way as well.

It's been a lot of talk and we've run the gamut of options but this is the year we build and I'm so excited!

Michael,
Wow! Thank you so much for all the great info! Since I don't have any appliances yet to judge their power usage I've just been plugging them into solar estimate websites to try and get an idea of how much power different appliances eat. Looking at what you've been accomplishing, I feel pretty confident that a 10.8kw system should be able to keep up with a small household pretty well.
Do you run solar only?
Thank you again!

Anne-
I had originally been hoping for a whole house system though I'm afraid that might have been a little bit of false hope lol. It would be the ideal, but I think I was underestimating how much power appliances use. We wouldn't have an A/C but things like washer dryer water heater fridge freezer etc...

Thank you guys so much for the info!
Sounds like solar is going to be more costly than I had anticipated, though if I can keep my usage down I'd be willing to spend more upfront if I could prevent those huge power bills.
Fwiw, in my area I've seen bundles of solar panels called a 10.8kw system, 27 panels, for sale under 10k. If Im doing this right that would mean it's 27 400w panels? If it's something even remotely feasible I'd jump on board with that.
Since the house isn't build yet I'll need to do some research to see what our usage would be with various appliances; thank you guys so much! I really appreciate it!

Hey all-
I'm a complete idiot when it comes to electrical (including solar) and I'd really appreciate some advice from you smart folks.
My husband and I will be beginning to build on our homestead this summer. In the woods where we are building, we are a ways from the power lines and we'd be looking at about $6k just to run the lines to connect. In addition, our power company is really expensive- roughly 270/mo for your typical house (wood heat and propane stove).
I like the idea of simply setting up a solar system instead, I feel like 6k could get us a good head start on a solar system instead of just paying to connect to the grid.
But how much can a solar system support? I know the answer is "it depends", but if, for example, you can power a 'typical' house with say 4 panels (I made that up, I don't know how many you need), could you just buy twice as many panels and batteries and then use an electric water heater instead of a gas one, say? Or triple the size of the system and heat your home with an electric tankless water heater running radiant in floor heat? (We're in northern MN- heat is a huge cost in our area)
If you can power more electric appliances by buying more panels and batteries, it seems like it'd be a worthwhile investment to build a bigger system off the bat and save in the long run.
My idea was to combine a bunch of solar panels with wind turbines and have a generator as backup.
But I'm sure I'm missing something, like I said, electricity is not my strong point.
Can anyone give some advice? Or point me toward some educational resources so I can wrap my head around what is feasible and what I need?
Thank you guys so much!

Thanks everyone for the replies!
I appreciate all the info, very excited to move forward with these earthen floors. Also, thank you for the info on aircrete, the more research I do I believe this is about the perfect building material for our cold climate. I think combining the insulation of aircrete with the thermal mass of earthen floors and a masonry heater should work together to keep our upcoming home nice and toasty.
If anyone has more ideas, keep em coming! What a wonderful community, looking forward to kicking around more ideas with all you great people!

Hey all! I have a question that might be stupid but here we go anyway.

I'm in the planning stages of a home. I'd like to do aircrete wall panels with earthen floors, but I'm having a hard time figuring out the issue of a foundation. Ideally I'd like to do a rubble trench foundation. I really don't like the idea of a concrete slab- the idea of walking on concrete for the rest of my life seems unpleasant. We're building in northern MN, and the typical foundations here are slab on grade or basements.
My idea was to do a rubble trench foundation with an insulating frost apron, but instead of a concrete slab use some kind of natural material, a layer of insulation, then an earthen floor with radiant heat. My husband is concerned that without the concrete slab the house would be more susceptible to shifting from freeze/thaw. I haven't been able to find anything online about a slab-free foundation that isn't a crawlspace.
Has anyone here had experience with this? Or maybe know a guy who knows a guy who's done something similar? I'm not even sure if it's a viable option, but any info or ideas would be greatly appreciated.
Thanks!