"sx460" wrote in message
...
Hello guys,

I'm planning on rerunning the duct work in my house and replacing the
furnace. My question for you is: how many BTU furnace should I buy?

I live in Iowa where it can get VERY cold, and for days on end. We've just
reinsulated the exterior walls with R13 fiberglass insulation (best you
can
get for 4" studs). Also, replaced all sheathing, wrapped the house, and
installed vinyl siding. Livable above ground area is 1,000 sq. ft. The
house
is also two story. Basement area is ~450 sq. ft. We haven't installed the
insulation in the attic yet, but it will most likely be in that 40-50 R
value range.

Thanks!



Do a heat load on the house. That's the only way to tell what you need.
DON'T look at a similar house and say "Since that's the same size as mine,
I'll put in the same size furnace." It doesn't work that way.