Hi. I have to regularly access corners of chimneys in the line of my work,
and sometimes you obviously don't want to tread on the tiles but you can't
go over the chimney to get to the other side.......

I have been told about something called a "creeper board" but I can't find
anything about it. My work only involves small periods of time at a given
chimney, so if it exists it would need to be something I can carry up on the
cat ladder and then take down an hours or so later when I am done.