help me with this please..

I'm writing an essay about living longer... so I have to write about overpopulation, consequences of living longer...
and I wanted to know how to write something about housing problems like for example:

"There would not be other way than just building not on the surface but (.. I want to write that we would have to build houses in the sky or something like that, but I don't know what verb exactly I can use.

If yo could help me please, leave a comment. Change the previous sentence if you want.

Correction:
 
There is no other way than not building on the surface. Houses would have to be suspended in the sky.