Post by gadget on Nov 26, 2018 10:14:11 GMT -8
So I finally am starting my heater build and am having second thoughts on a mass heater. My problem is its over a basement with 2x8 subfloor joist. Heater will be in the corner on the second floor. Originally there was going to be a side bench along an external wall. I was going to sister 3 of the joist and sister the wall studs.
Then changed to my final design, do a vertical mass heater with a vertical mass in the basement supporting the upper mass upstairs - No bench. Firebox would be upstairs with 2 bells in the basement mass below. There is no chimney in this system but lets not open up that can of worms in this thread. The burn box would sit on top of a third small bell/mass so it would be 20" above the wood floor on the upper level. Basement is concrete.
So here is my two options. The lower mass will not be carrying the weight but instead just be inside some steel beams that are supporting the upper weight. I figure I can keep the flooring MDF/Plywood upstairs and raise the 3rd bell up on a few bricks/plus insulation. The burn box would sit ontop this third and last bell. Then just run the exhaust pipe through the floor then back again from the lower bells.
Other option is the cut the flooring out leave the 2x8's, insulate them from the pipe and mass and run the mass up higher through the floor???
Third option is probably the best but I will not do it due to the amount of engineering needed, cut the floor joist and box it all in leaving a giant hole the heater can pass through making a one piece monolithic heater. This is probably the best option but I just can't commit to that kind of work right now.
Here is my thought now, my burn chamber is going to be built into a metal box fully ceramic wool/board insulated already why not just build in a water heat exchanger after the air exchanger and use water as mass. I already have a 104 gallon Rheem insulated Marathon water tank in the garage that is 4 feet away and I could use that as storage, then run some PEX under the flooring to all the rooms. Dang, I really like the idea of making this more simple, then maybe ad some mass later. Since I am not running a chimney, All I would need is some heat protection similar to a wood stove, probably less since this thing will be fully insulated on the inside.
Please share your thoughts, I'm pulling the trigger this week and starting.
I envy all you that have cement pads to work with.
Then changed to my final design, do a vertical mass heater with a vertical mass in the basement supporting the upper mass upstairs - No bench. Firebox would be upstairs with 2 bells in the basement mass below. There is no chimney in this system but lets not open up that can of worms in this thread. The burn box would sit on top of a third small bell/mass so it would be 20" above the wood floor on the upper level. Basement is concrete.
So here is my two options. The lower mass will not be carrying the weight but instead just be inside some steel beams that are supporting the upper weight. I figure I can keep the flooring MDF/Plywood upstairs and raise the 3rd bell up on a few bricks/plus insulation. The burn box would sit ontop this third and last bell. Then just run the exhaust pipe through the floor then back again from the lower bells.
Other option is the cut the flooring out leave the 2x8's, insulate them from the pipe and mass and run the mass up higher through the floor???
Third option is probably the best but I will not do it due to the amount of engineering needed, cut the floor joist and box it all in leaving a giant hole the heater can pass through making a one piece monolithic heater. This is probably the best option but I just can't commit to that kind of work right now.
Here is my thought now, my burn chamber is going to be built into a metal box fully ceramic wool/board insulated already why not just build in a water heat exchanger after the air exchanger and use water as mass. I already have a 104 gallon Rheem insulated Marathon water tank in the garage that is 4 feet away and I could use that as storage, then run some PEX under the flooring to all the rooms. Dang, I really like the idea of making this more simple, then maybe ad some mass later. Since I am not running a chimney, All I would need is some heat protection similar to a wood stove, probably less since this thing will be fully insulated on the inside.
Please share your thoughts, I'm pulling the trigger this week and starting.
I envy all you that have cement pads to work with.