Hello,
How many BTU or tons's of a/c is required to cool a 1080 sq foot house?

Here is a handy link that will help you with this problem.

I've used it a couple of times myself.

Air Conditioner BTU Calculator - Goodhousekeeping.com (http://www.goodhousekeeping.com/home/air-conditioner-calculator)

I think you already knew the answer... or at least, knew where to find it.
A Google search... "btu's to cool 1000 sq. ft of house"... gave me this:

Look for this size air conditioner


100 to 150 square feet


5,000 BTUs


150 to 250 square feet 6,000 BTUs


250 to 300 square feet 7,000 BTUs


300 to 350 square feet 8,000 BTUs


350 to 400 square feet 9,000 BTUs


400 to 450 square feet 10,000 BTUs


450 to 550 square feet 12,000 BTUs


550 to 700 square feet 14,000 BTUs


700 to 1,000 square feet 18,000 BTUs


1,000 to 1 400 square feet 24,000 BTU's

I think you already knew the answer.......or at least, knew where to find it.
A Google seach..."btu's to cool 1000 sq. ft of house".....gave me this:

Look for this size air conditioner


100 to 150 square feet


5,000 BTUs


150 to 250 square feet 6,000 BTUs


250 to 300 square feet 7,000 BTUs


300 to 350 square feet 8,000 BTUs


350 to 400 square feet 9,000 BTUs


400 to 450 square feet 10,000 BTUs


450 to 550 square feet 12,000 BTUs


550 to 700 square feet 14,000 BTUs


700 to 1,000 square feet 18,000 BTUs


1,000 to 1 400 square feet 24,000 BTU's



You really need to do a Manual J to be accurate. Windows, insulation,sun side,ETC. are all needed to be accurate. A guess might work but if it is to large or to small it will never work correctly.

Just for fun try this diagram.

More accurate, easier on the eyes than the Good Housekeeping, plus gives a recommended unit: Air Conditioner BTU Calculator (http://shinydonuts.com/airconditionercalculator/airconditionercalculator.html)