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It is a privilege to live, work and play in the traditional territory of the Salish People.
Now drop and give me 52... ~ Come Join the permies Shoecamp! ~ All about Permies, including Tutorials ---
Twenty bucks off the homesteading bundle for the next 72 hours!
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Jan White wrote:That's about the size of our house. We've got a super basic metal box wood stove, about 15x20". I would hate to have that thing going long enough to even boil a bit of water in the summer. Even in winter, it's sometimes hard to run it hot enough for long enough to cook anything substantial without heating the house up unreasonably. I realize you'll have the mass absorbing heat, but still, it might be tough to make it work all year.
Another thing about cooking in such a small space is it produces a lot of humidity. And all your clothes smell like whatever you cooked for three days afterwards.
'Theoretically this level of creeping Orwellian dynamics should ramp up our awareness, but what happens instead is that each alert becomes less and less effective because we're incredibly stupid.' - Jerry Holkins
125 mm — 3.5 kg — 1.1 kW
140 mm — 4.9 kg — 1.5 kW
150 mm — 6.0 kg — 1.9 kW
175 mm — 9.5 kg — 2.9 kW
200 mm — 14.2 kg — 4.4 kW
230 mm — 21.6 kg — 6.7 kW
250 mm — 27.8 kg — 8.6 kW
It is a privilege to live, work and play in the traditional territory of the Salish People.
Now drop and give me 52... ~ Come Join the permies Shoecamp! ~ All about Permies, including Tutorials ---
Twenty bucks off the homesteading bundle for the next 72 hours!
'Theoretically this level of creeping Orwellian dynamics should ramp up our awareness, but what happens instead is that each alert becomes less and less effective because we're incredibly stupid.' - Jerry Holkins
D Nikolls wrote:
I think the first three numbers are just... wrong, by a fair bit.
8100BTUs sounds like a reasonable number to target for a propane or electric unit with a bit of extra capacity. I don't know that there is an exact conversion to wood, but I'd round up again..
My tinyhouse is 28ft long by 8.5 wide, no loft. 2x8 floor, 2x6 roof, 2x4 walls, all with roxul. Additional 1.5" roxul on the outside of the walls. So, very similar, a bit less insulation in the walls, which the broken thermal bridging in my build probably more or less balances out..?
Figure my site gets a little colder than yours, I'm in the comox valley, not too near the water.
I don't have my HRV installed yet, so there is a bit of loss to a cracked window in the winter, but otherwise it's pretty tight, and has relatively little window area at about 35 square feet.
My direct vent propane heater has a rated output of 8800 BTU.
So, that is about a 2.6KW rated output.
Judging by duty cycle, it's had a little capacity in reserve down to the lowest temps I have seen here, -10c nighttime lows; it has never failed to keep the house as warm as I want, which is usually pretty darn warm since I spend all winter struggling to dry out A) lots of wet work clothing, and B) the house itself due to all this humidity. Maybe it has 15% reserve on the coldest nights?
Obviously this is not a science, but I am at least confident that it has SOME headroom left, and that it does not have anywhere near 50% reserve capacity.
My feeling is that a 6000BTU output would be getting down to the minimum for those coldest nights. It's already a moderately slow process to warm the house from 5C in cold weather...
I am hoping to get a woodstove installed this summer, to cut propane out barring backup and extended absences. I am thinking a 5KW stove.
A 2.6kw rated woodstove would put a LOT less heat into the space in 24h vs the 2.6KW propane unit; there is some time wasted as the fire gets going, then somewhat variable heat output as the fire hums along, fades, is fed, hums along, fades... Most days, I'll be outside, and the fire will probably be embers or dead when I get back at lunch and dinner... All extra pronounced with such a small stove needing relatively frequent feeding.
And then you go to bed and the heat fades out in... 3 hours, maybe? So, I am rounding up, to try and get a similar total daily BTU output...
OTOH, you can warm yourself directly in front of a woodstove much more effectively; the heat from the propane unit goes up, no real radiative heating to speak of...
(Unrelated: If you are not striving to be under highway max height, why not a thicker ceiling? A good place to pick up some efficiency.. I am intending to redo mine with much more insulation now that I don't intend the house to travel highways again.)
It is a privilege to live, work and play in the traditional territory of the Salish People.
Now drop and give me 52... ~ Come Join the permies Shoecamp! ~ All about Permies, including Tutorials ---
Twenty bucks off the homesteading bundle for the next 72 hours!
It is a privilege to live, work and play in the traditional territory of the Salish People.
Now drop and give me 52... ~ Come Join the permies Shoecamp! ~ All about Permies, including Tutorials ---
Twenty bucks off the homesteading bundle for the next 72 hours!
“Uncertainty is an uncomfortable position. But certainty is an absurd one.”
― Voltaire
I currently cook with propane, and extended cooking times in summer is Not Good;
John Daley Bendigo, Australia The Enemy of progress is the hope of a perfect plan
Benefits of rainfall collection https://permies.com/t/88043/benefits-rainfall-collection
GOOD DEBT/ BAD DEBT https://permies.com/t/179218/mortgages-good-debt-bad-debt
John C Daley wrote:
I currently cook with propane, and extended cooking times in summer is Not Good;
I am surprised about this point. Surely with ventilation things would be ok?
I use a propane cooker and have never had an issue in summer.
'Theoretically this level of creeping Orwellian dynamics should ramp up our awareness, but what happens instead is that each alert becomes less and less effective because we're incredibly stupid.' - Jerry Holkins
'Theoretically this level of creeping Orwellian dynamics should ramp up our awareness, but what happens instead is that each alert becomes less and less effective because we're incredibly stupid.' - Jerry Holkins
jordan barton wrote:
D Nikolls wrote:
I think the first three numbers are just... wrong, by a fair bit.
8100BTUs sounds like a reasonable number to target for a propane or electric unit with a bit of extra capacity. I don't know that there is an exact conversion to wood, but I'd round up again..
My tinyhouse is 28ft long by 8.5 wide, no loft. 2x8 floor, 2x6 roof, 2x4 walls, all with roxul. Additional 1.5" roxul on the outside of the walls. So, very similar, a bit less insulation in the walls, which the broken thermal bridging in my build probably more or less balances out..?
Figure my site gets a little colder than yours, I'm in the comox valley, not too near the water.
I don't have my HRV installed yet, so there is a bit of loss to a cracked window in the winter, but otherwise it's pretty tight, and has relatively little window area at about 35 square feet.
My direct vent propane heater has a rated output of 8800 BTU.
So, that is about a 2.6KW rated output.
Judging by duty cycle, it's had a little capacity in reserve down to the lowest temps I have seen here, -10c nighttime lows; it has never failed to keep the house as warm as I want, which is usually pretty darn warm since I spend all winter struggling to dry out A) lots of wet work clothing, and B) the house itself due to all this humidity. Maybe it has 15% reserve on the coldest nights?
Obviously this is not a science, but I am at least confident that it has SOME headroom left, and that it does not have anywhere near 50% reserve capacity.
My feeling is that a 6000BTU output would be getting down to the minimum for those coldest nights. It's already a moderately slow process to warm the house from 5C in cold weather...
I am hoping to get a woodstove installed this summer, to cut propane out barring backup and extended absences. I am thinking a 5KW stove.
A 2.6kw rated woodstove would put a LOT less heat into the space in 24h vs the 2.6KW propane unit; there is some time wasted as the fire gets going, then somewhat variable heat output as the fire hums along, fades, is fed, hums along, fades... Most days, I'll be outside, and the fire will probably be embers or dead when I get back at lunch and dinner... All extra pronounced with such a small stove needing relatively frequent feeding.
And then you go to bed and the heat fades out in... 3 hours, maybe? So, I am rounding up, to try and get a similar total daily BTU output...
OTOH, you can warm yourself directly in front of a woodstove much more effectively; the heat from the propane unit goes up, no real radiative heating to speak of...
(Unrelated: If you are not striving to be under highway max height, why not a thicker ceiling? A good place to pick up some efficiency.. I am intending to redo mine with much more insulation now that I don't intend the house to travel highways again.)
thanks D for the reply
Yea the numbers were throwing me off a great deal. I however am assuming heating with propane vs heating with a masonry type stove would be much different. The propane heats the air where as the stove would radiate the heat it stored during firing. I expect the btus to heat with propane to be much higher.
During the winter i am at home most of the time only leaving to go to work or social functions. Max i would be away is 6+ hours. I also have goats to manage so i need to be here morning and at night time. So i will most likely not need to warm it up from 5*C i hope!
Last winter we received a -10 without snow for a few days. in the current house i am in. it made the floor really cold. The cold would travel up my chair and cool my body down. i had to insulate my chair in order to be able to sit down for extended periods. I was reading 48*F with my infrared gun on the floor! To help mitigate the cold spell. I added about 100 clay bricks around our wood stove and changed the baffle so the stove became much hotter before leaving thru the chimney. That helped a lot. Now i could fire the stove at hot temps without losing all the heat to the air.
Yea i could go with a more insulated roof, However i was thinking with it being such a small space, if i need to run the stove a little longer due to that i could live with it. Especially because i work at a sawmill and get all the offcut/scrap lumber.
At the moment i am thinking i have a pretty well insulated space and would like to see how it performs. I was thinking i could change it if required. How do you plan on changing your roof? taking the roof off and adding 2x10 rafters?
One thing i could do is make the ceiling somewhat suspended and add more insulation once the rest of the building is closed in.
I did just spend 2133.60 dollars on insulation, tyvex and vapour barrier!
The tiny house might be moved. maybe not moved at all. its unclear at the moment. the biggest concern actually has to do with our narrow roads. 10 feet is really the max i can make this building and still be able to skid it around. There might be roads where i would not be able to go down them.
'Theoretically this level of creeping Orwellian dynamics should ramp up our awareness, but what happens instead is that each alert becomes less and less effective because we're incredibly stupid.' - Jerry Holkins
John Daley Bendigo, Australia The Enemy of progress is the hope of a perfect plan
Benefits of rainfall collection https://permies.com/t/88043/benefits-rainfall-collection
GOOD DEBT/ BAD DEBT https://permies.com/t/179218/mortgages-good-debt-bad-debt
For all your Montana Masonry Heater parts (also known as) Rocket Mass heater parts.
Visit me at
dragontechrmh.com Once you go brick you will never go back!
John Daley Bendigo, Australia The Enemy of progress is the hope of a perfect plan
Benefits of rainfall collection https://permies.com/t/88043/benefits-rainfall-collection
GOOD DEBT/ BAD DEBT https://permies.com/t/179218/mortgages-good-debt-bad-debt
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