In the wild B.c.i's are found over 36" above ground. I cannot speak for your dwarf boa, what locality is it? On some level you never know what they will like or dislike ultimately. I've done setups for some pets that I thought they would take to, and ended up the pets did something completely different. I know a B.c.i (non-dwarf) would use upwards of 6 ft of vertical climbing space as I have seen that personally.