While it is expected that the 1100mm guarding height in Approved Document O is achieved, a reasonable build tolerance is +0 / - 100mm.
Er y disgwylir i'r uchder gwarchod 1100mm mewn Dogfen Gymeradwy O gael ei gyflawni, goddefgarwch adeiladu rhesymol yw + 0 / - 100mm.