Walls and Ceilings - breaking hole in stucco for plumbing

My hot water heater is outside. There are pipes that go to it but they use the nylon hose to go through the wall. I need to replace it with solid copper piping.

So I went to bust a hole through the stucco.
After I got through the stucco and chicken wire there's plywood. Should I just saw through that to get all the way into the wall?

Welcome tothe forums!

I assume your water heater has protection from the elements ???

Yes, you need to drill thru the plywood. Use care so your bit doesn't get tangled up in the wire lath. You also want to go slow if there is any danger of wiring or other mechanicals in that area of the stud wall.

Welcome to the forums! Not sure where you live, but a water heater outside can't make for good economy in that respect. But to answer your question, use a 1" spade bit and drill through the stucco and lath. Pull the bit out and clear the end of the metal that will be stuck to it. Then drill through the wood. Make sure you aren't drilling through a framing member. It will probably waste the bit, but you will get a clean hole. Be sure to silicone around the entrance of the pipes into the stucco to prevent water infiltration.