Algodoo

Inspired by "Tornado Alley Kit" by TornadoAlley, I remade it into this.
There's a boardwalk town to test them on
Grey buildings (Hotels) have 4 layers
Red buildings (Houses) have 3 layers, making them weaker and destroyable by an EF 2 and above
The boardwalk can be destroyed, too.

How to make a building:
1) get up to 4 squares
2) make the 1st one collision layer D, 2nd one C, 3rd B, and 4th A.
3) cut them into peices (As many as you would like
4) put the "A" block on bottom, followed by B, C, and then D
4.5) If you only have 3 or less floors, start with B, then C, then D
And you're done!