its all about the ground. If you stuff the starting point into the terrain and go across to meed another tile stuffed into the terrain, and use ironwood supports, its about 20 or so 2x2 floor tiles. Additional support up from the ground or on the diagonal etc will add a bit more, but exceeding 30 by much without a true ground point somewhere else is going to be tricky. If you go up from ground and then across, it cuts your distance quickly.