I recently went through a PVC pipe fitting break in my newly purchased home. Flooded the master bath, closet, toilet room, bedroom and hall. Luckily I was home or it would have been worse.
My State Farm home owners insurance covered the resulting damage and repairs (less deductible) but did not cover any plumbing costs to repair the break. Reasoned it was maintenance. While I had the wall open I changed everything to copper fittings for which I paid out of pocket. Plumber said it wasn’t necessary but I would rather be safe than sorry. Sounds like that was a prudent decision.
I was told by my Realtor that when they replaced the Kitec piping they ran the new lines up the walls and through the attic. Do not put a nail or screw in the wall unless you know there is no piping behind it and be diligent about checking below and around your bath and kitchen fixtures. Feel for any moisture inside the cabinet, on the piping, drains and around base of fixtures. Look for discoloring since our hard water leaves deposits. Also, walk outside and look closely at the walls if your bath borders an outside wall. I’ve become more proactive about checking for problems on a regular basis.