wrote in message
s.com...
Durock, hardi-backer, wonder board etc. I assume some type of carbide
drill bit but what is it called? Holes big enough for pipes and
shutoff vales. Thanks.


Masonry bit? You can use a small one and drill multiple holes for smaller
openings, then break out the middle. Or drill corner holes and use a carbide
blade in a sabre saw. You can use regular steel bits and blades, but they won't
last long. A 1/8" carbide cutting bit in a dremel tool or other high speed tools
works very well. For longer straight cuts, score and break, or used a masonry
abrasive blade in a circular saw (but don't breath the dust).

Bob