Hi again everyone,
So I used this heat loss calculator, https://www.builditsolar.com/References/Calculators/HeatLossOld/HeatLoss.htm
and this R value calculator for the wallshttps://ekotrope.com/r-value-calculator/
I have balloon framed house with an EIFS exterior (which includes a layer of styrofoam) and mineral wool on the inside. To be conservative, I gave the assembly an R-value of 7.
To give an example, I have a bedroom with two exterior walls, 1 window, 1 sliding door, and the dimensions are about 14 x 16. It is on the second floor of a three-story house. I come up with 209 sqft of wall, 11 sqft of window, 32 sqft of door, and the calculator says the heat loss is 4460 BTU/hr. This seems to be plenty, as the room currently has a 4 foot section of fin tube, which I estimate to put out 4000 BTU, and the room heats just fine. So, that just confirms my R-value is on the conservative side.
1. Does that sound right to you? I read somewhere that a rule of thumb is the square footage x 40, which gives me 8960. Is it possible I am off by a factor of two, or is it just the difference between rule of thumb and actually calculating it out?
2. If I go through the house and replace some radiators with smaller ones based on the heat loss calculation, will that mess up the balancing for the old radiators that stay? Will I need to replace the air vents with different sizes to keep everything balanced? (I have one-pipe steam, BTW) My gut says no, but I wanted to check.
Thanks in advance, you guys are awesome.