Mort Smith wrote:So I sent Erica an email and she requested I post them here to make the discussion more available to people - so here goes!
So I saw a video on youtube (https://www.youtube.com/watch?v=6lUCOowOmJ8) where you were installing and demonstrating using a rocket heater as an underfloor heating system and the switch between the short path exhaust and the long path to heat the subflooring area. I thought it was brilliant.
1. - How did that turn out? Was it as successful as you expected? Did the heating dry out the wood floors? Would another floor surface work better?
Mort Smith wrote:
2. How much floor space would a system built that way heat? I'm looking to build an oregon cob home (in Oregon or Washington, land prices/availability at the time kind of deciding where I purchase this year) with an internal floor space of approximately 20'x25'. Ish. Subject to some minor revision - but the end result will still be in that ballpark for total sqft or smaller. It's a lot of cob to make after all. EDIT: In fact, it's hella a lot of cob to make and I'm seriously considering straw bale instead - it's already covered in the Oregon building code (permits! YAY!) and much easier and faster to do.
Mort Smith wrote:
3. Would that be too much space for one underfloor "long path" to handle? I understand that there is a limit to how far the exhaust can be pushed/pulled through the system and don't want to overload it - math is not my strong point, but I definitely get it enough to know there are limits.
Mort Smith wrote:
Here's my thought if it was - since you created that whole nifty switch thingy - what if there were two separate "long path" duct systems built under the floor - could you heat one, then the other using the switching system? Say I want the kitchen and main living area toasty toes primarily during the day, but then I want my sleeping area on the other end warmed up before bedtime. Or if it's really butt ass cold outside - do one and then the other right after, alternating the firings as needed.
Is this a viable idea? Because I really want it. Since cob requires a solid foundation anyway, putting in a subfloor shouldn't be an issue. I was thinking about a tiled floor, but I am totally open to suggestions that would enhance the heating properties.
Mort Smith wrote:WOW - that is an enormous amount of information, thanks! I'm going to have to digest it and come back to some of the questions I have now - after I do some calculations, look at my blueprints and have a bit more caffeine myself.
I'll likely be more inland dealing with harsher winters, it's cheaper than coastal land and I'm on a budget. I've lived on the boat a couple of years now, so winter on a boat is the normal state of things - a little bouncy, but comfortable other than that. I've pretty much decided to go with the straw bale construction - it's got a lot of benefits aside from easier and more cost effective to do in a short period of time. The layout is very open plan for the house - and I plan to put in a dutch bed rather than a full bedroom. No kids, just me and the cat. The loo will be enclosed, but that's about it really. I'm glad to hear tile is a good choice, I think it really compliments the whole "cottage" look, and is easier to take care of than wooden floors. I want to go with fairly thick tiles (3cm) probably handmade and decorated on site because I'm a nerd like that. I'm definitely not a hot air in the room kind of person, basically as long as my feet are warm, so is the rest of me. I can always put on a sweater.
I do like the idea of a radiating wall though, perhaps that can be worked into the plans somehow - and I'm not opposed to putting the barrel in the middle of the room if it had a radiating wall behind it that was a couple of feet wide - not truly dividing the space, but making good use of the heat and didn't seriously impede flow of traffic. That would allow for fairly even paths under the floor on either side of the wall to get to maximize the heating areas. The math - I'll have to do some drawings and fiddle and get back on that bit when I'm more caffeinated, I was a wake a 5 am myself, so I just woke up and I'm still not up for math yet.
I appreciate your time and very in depth response! I will no doubt have more questions, but not yet.
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