UP: How many helium balloons would it take to lift a house?

After seeing UP by Pixar this weekend I wondered how many balloons it would take to life a house.

According to this site, a house without concrete floor slabs weighs between 80,000 and 160,000 pounds.  http://seattletimes.nwsource.com/html/asktheexpert/2002122968_homehay19.html

And according to this next site it takes 34 large balloons to lift 100 kilos.
http://my.bubblexl.com/blog/?p=12

So assuming a house with a weight of 100,000 pounds or 45,340 kilos we would need 15,402 large balloons from BubbleXL.  At a cost of 17 Euro each this cost about 261,000 Euros.