Up, Up, and Away!

How many standard balloons would it take to lift an average house?

It will take 2.5 million standard 11'' balloons will lift an average 5 bedroom house.

If each balloon is 11'' in diameter, and the average house weighs about 350,000 pounds, it will take 13,461,538.461 balloons filled with helium to lift the house.

Reasoning Behind It: An average #2 pencil weighs about 0.425 ounces, that's 0.026 pounds. So my educated guess is a single 11'' balloon filled with helium can lift around one #2 pencil. 350,000/0.026 is 13,461,538.461. So my educated guess is it will take 13,461,538.461 11'' helium - filled balloons to lift an average 350,000 pound house.