All good points. This season, I brooded 48 LF chicks with 2 XXL Sunbeams. B/C of the lay out of my brooder/coop, I did not find it practical to do the 12 x 48" configuration. So I messed around with making an L shape, but was not happy with the support system I had in place for that. I ended up placing the standard caves beside each other, with about a 4" "walk way" between them. IIRC, I raised the front 12" W section of each pad so that they sloped down at only the back 12" section of each pad, providing them with exit from both 12" front sections, the 4" pathway, and both 24" sides. It worked well, with the chicks seeming to be plenty warm, and using that pathway as yet an other place to stay warm while viewing their world.