My data on weighed wood burns might have induced some of you to also do this for a sufficient period of time to use that data to calculate actual heat loss. My boiler and storage are inside the heated space. For Nov-Dec I burned 3014 lbs of wood. That works out to 12,455 btuh actual heat loss (3014 x 6050 / 61 / 24). Degree days in my location for these two months were 1993, which also means, fwiw, 6.24 btuh/dd. My shop is kept at 60F, so my heat loss does not represent an equivalent house. If some have boiler and storage inside the heated space and could do the calculation, and others have the same outside the heated space and do the calculation, we might start to get a better idea of the contrast from a heating perspective of boiler and storage location. You might want to try weighed wood burns for awhile and see what the result is for actual heat loss for your home or other building.