The previous owners had a half built rock pad. Put up an 8'x'8 form, 22 80lb bags later, and covered it up. The nc30 will be getting installed black Friday. Nothing fancy, but hoping the thermal mass might help distribute some heat. Needing to build a cart still, would like to load wood through the window....
nice job tuneighty ... do not know if that block wall is insulated.... if not you might want to consider it as concrete has an r value of about 1 if on an outside wall you could be dissatisfied with amount of heat you get..
It has about 2' above grade. I would think the below grade is considered insulated ? Tonight with the forms off...
That option was brought to my attention, I chose to increase mass in the basement. The pre existing slab was almost 7'x6', and 4" high...
Below grade takes on earth temperatures. It is better than a cold wind but is still much cooler than a heated room. You will lose heat through the ground contact as well.
Rammed earth, stones and concrete can store energy. It helps on the vertical walls if you can get the dirt as dry as possible ( drain roof water far away ). Hollow concrete blocks above grade can be ice cold. I've got solid 12 inch thick concrete walls and they can take all day to warm up with the wood stove in the basement but after that they are nice and warm.
