The amount of BTU's per square foot varies. The BTU's per ft2 in my area is 30-35. In your area there might be more or less.
For reference sake... Btu's are not used in Metric settings, Joules are used.
1 btu = 11356 joule
Contact a HVAC tech in your area. They can tell you the recommended BTU or JOULE rating for your area with the use of a manual known as a "J manual"
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To be proper, BTU should be all capitals as in the first sentence, though correct abbreviations are very awkward to use in many Microsoft applications!
Answer SaveA square meter of what? A BTU is a unit of energy, so the question can't be answered without more information. I try to calculate as per following:Roughly Btu's per sq.ft is 30.25.Since 1 square foot = 0.09290304 meters squared and can easily be calculated asBtu's per sq.meter is roughly 344.4451.So the space of 1 sq.meter room is 344.4451 BTU.
you can use easy way 25 square meter*3.281*3.281*80/ 12000 1.79 ton
There is no conversion. A cubic meter is a unit of volume. A BTU is a unit of energy. Apples and oranges...
About 365 square feet.
400 to 450