So we didn't get our RMH started in the warmer part of the year. Our house build was delayed for many reasons and by the time we finally got "dried in", temperatures were regularly below freezing at night.
Can't build a RMH when it's freezing, right? Frost heaven would knock everything off level. So then we needed to insulate the ceiling at least. But had to put in electric wires before putting in the insulation. So more delays.
Finally we're ready to start building the RMH but now it's snowing. Used a propane heater to keep the stove from freezing during the build which worked fine but cobbing is more difficult.
First you need to figure out which of the white lumps outside was the pile of clay. Then scrape off the snow. Next chip off the top couple of inches of clay which are actually frozen. Once you"ve found the unfrozen clay, load up the wheel barrow but only 1/2 way because wheel barrows don't roll very well at all in several inches of snow. Wheel it the 50 feet or so to the house. Up and over the step and the threshold. Into the house, and dump it out onto a large tarp. Add water, sand and straw and stomp, stomp, stomp. Don't dare do this barefoot though. Some of the clay is still frozen and the rest of it is nearly so. Snow boots are in order for this. Fold the tarp over to flip the mix.
Finally mixing by hand but the darn stuff is so cold that my fingers go numb through the rubber gloves. Thank goodness I can run the RMH during the cobbing of the mass. I need to stop frequently to thaw out my fingers.
It's all worth it though as the bench starts to slowly take shape and the temperatures of the house slowly rise.
Outside temps 22 deg, inside high was 55 deg today. Quite comfortable while working around the RMH. Our house has a large thermal mass behind the back wall that unfortunately got quite cold from snow melt falling off the roof and getting past the plastic and into the earth. Going to take a bit to warm it back up but we're well on our way now.
Well done. I am admiring your perseverance and not letting circumstances get you down. Looking forward to updates and seeing you guys toasty warm in no time!
Great Job Penny! Looking good! All I can say is chin up and keep cobbing! And keep the photo's coming!
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Hi Penny; Just a thought, are you using hot water in your mix???
I added my ingredients to the tarp and then folded it over to stomp on. And again and again until its right.
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!
That's the spirit Penny! Nothing like the cold to give a boost to getting things done knowing that it will make you warmer not only once the fire is going but also while your working.
As others have mentioned, we like pictures!
Unfortunately, we don't have running water yet or an easy way to heat it at the house we're building.
So the water even has ice in it sometimes. I do throw the ice back in the water bucket when I pour the water on the mix.
I tried doing lasagna cob today which seemed easier. Light layer of straw on the tarp then the clay, throw some sand on it and then more straw and top it with some water. Stomp, stomp, stomp. Fold with the tarp and stomp some more.
House held at 40 deg last night when it was about 15 deg outside. Only up to 55 deg again today while I was cobbing again.
Is there a temp limit to how hot the 55 gallon drum should get? I've had it up as high as 700 deg.
Penny McLoughlin wrote:Is there a temp limit to how hot the 55 gallon drum should get? I've had it up as high as 700 deg.
I'm assuming from your photos that the temperature is being taken at the top side of the barrel. From many people reporting here, for an 8" system this sounds about right. But the top of the barrel can get over 1000F and the spot right above the heat riser can be glowing red when you really get it ripping.
How big is your top gap? (The space between the top of the heat riser and the barrel). - Generally, the greater the distance the lower the temperature will be.
I had about 3 inches but I think the rounded lip that I had made out of ceramic clay on the top lip of the heat riser sort of exploded off when I first got the stove good and hot. So might be closer to 4 inches now.
Glad to hear that's a normal temperature.
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