Options per variant

I'm building a quite complex webshop/catalogue. It has lots of gardenhouses, and every house comes in different sizes. I created charactaristics for the sizes. The customer should be able to choose some options. These options also depend on the size they choose (eg a wooden floor in the garden house depends -of course- on the size of the house).

Is it possible to add options to the variants? Or any other idea on doing this?

thanks.