We went into Kamloops on Tuesday and exchanged the refractory mortar that did not work very well for a different product.
Right away we could tell that this was a much better mortar for this job; there was no large aggregate in it, and it was simple to brush a thin layer onto the bricks. We finished the brick work for the core of the stove on Wednesday. (I’ve included pictures at the end of this post.)
Other things we’ve been up to … we bought all of the 8″ flue and chimney pipe on Tuesday. This was expensive … all of the new piping cost over $1000.00 dollars. Over $400.00 of this bill was for 6′ of stainless steel insulated chimney pipe for the portion of the flue that is outside the building. Many rocket mass heaters have been successfully constructed with used pipe and the flue exiting out the side of the building without insulated pipe. This is safe with a rocket mass heater as the exit temperature of the combustion gas is under 200 degrees Farhenheit and does not pose a fire risk to framing or sheathing materials. We chose this more expensive route for the very simple reason that our stove is being built under a construction permit with our local building authority. So, our flue exits the roof of the building, and uses insulated stove pipe to protect the surrounding materials from excessive heat. We are using standard, 22 gauge, single-wall stove pipe for the flue of the stove. The design of the stove conforms to typical construction practices to simplify the process. The permit cost $150. Sandra was not happy about this, but managed to restrain herself.
Also, we tracked down a 55 gallon stainless steel drum to that we will use for the heat exchanger of our stove. It was hard to find a stainless steel drum locally … I did end up finding one in Salmon Arm finally (Tuesday was a long day) for $100.00. Originally, the drum held Tea Tree oil … the car smelled like Vick’s Vapour Rub all afternoon! Turns out the original drum we planned to use for the stove had a pinhole leak on its side. It was repairable but I wanted stainless steel originally so it worked out for the best.
Very cool! You know, if you want a source of cheap perlite, it’s a 100% waste product in a lot of 50’s bungalows torn down every week here in Vancouver – you find it a food deep in the ceiling. You can take as much as you want usually. The problem is, there’s a decent chance of there being a certain amount of asbestos in it. But heck, that’ll just improve the insulation value :-).