I already know what you are going to say "but there is no build height limit because etc" but there is. It is at about 1,000,000 100,000 blocks. I know because my current build goes that high and I have built that high before to find a block at the same height. It is mostly do to a glitch in the torque engine because it can not support more than 6 digits so it becomes impossible to line up ghost bricks to place bricks. You can work around this by forcing a load to load higher, but then all the blocks are misaligned floating and glitchy. So today you learned there is in fact a build height limit, you will just probably never reach it because it is crazy higher up. It takes like 10 minutes just to fall to the ground from that height.