How many BTU?

jbw

what do you recommend as the necessary BTU per square foot?

scrook_2

enough to...

overcome the calulated heat loss of the structure at design temperture -- materials of construction, amount of insulation, number of external walls, amount of glass/window area tightness/infiltration rate of the structure etc. all come into play. There is really very little relationship to sq footage (or even room volume, cu ft) other than big spaces tend to require more heat than little ones.

jbw

thanks for your advice. i have a family room that is 9x13 and was converted from an attached garage. there are two external walls, one of which is about half windows and the other has three small windows. because it was a garage, it is on a slab so the floor is often cold. is 4700 btu too little?

Doug Wagoner

Is 4700 BTU's enough?

Yes, it is plenty at some outside temperature. But the question is: what temperature? Go to the upper left corner and run a heat loss calculation. You can do this if you know the materials and type of construction used in this room. You must also know the lowest outside design temperature for the area of the country in which you live. If it all becomes 'greek' to you then you get a better picture of the knowledge and experience of heating pros.