Rod, above 3000feet you require 1000 feet vertical and 1500 metres lateral separation from cloud for VFR flight. One of the reasons for this is so that in the event of engine failure, a descent through cloud does not have to follow, ( with no AI) and gives time to glide through the hole through which the solitary blade of grass can be seen , so one foot above a broken layer would not be legal VFR. (unless climbing or descending, which arguably you could keep doing indefinitely!)
However the one foot would be legal if IFR, even on a basic PPL with no intrument qualification (if otherwise meeting VFR weather criteria) and provided that 1000 foot above obstacles within 5 miles of the aircraft is maintained . Thus in good weather, above three thousand feet, set 1013, follow the quadrantals, maintain obstacle clearance, skim the clouds, and regard yourself as IFR!
Edited to say sorry Rod , you actually said one foot below, not one foot above!
