Minecraft Dome Roofs Start With One Good Circle Every dome is a stack of circles that shrink as they rise. Get the base circle right and the rest is arithmetic: drop the diameter by 2, build one or two layers, drop it again. A diameter 17 base can step 17, 15, 13, 11, 9, 7, 5, 3, 1 for a smooth dome, or skip steps for a steeper roof. Alternate materials on a couple of layers - a ring of stairs or a band of glass - to give the dome structure. From the ground, those bands are what make a dome look designed instead of accidental. Leave the inside hollow. A dome of outlines uses a fraction of the blocks of a solid one and gives you a dramatic ceiling for free. Plan your own circle here: mc circle generator