Do you think a finish nailer has enough power to shoot a nail through a copper pipe? I'll spare you the research.....it does. It's difficult to do, of course. Most times, the nail will glance off to one side or another. If the stars align, however, and you get it juuuuust right, though, that nail will go right on in.
You might think that, having just shot a 2 1/2" nail into a 3/4" water supply pipe, you'd know....right? Actually, no, you probably wouldn't. You see, pneumatically driven finish nails are coated with glue. That glue is solid until the nail is fired. The speed with which the nail enters the wood.....er......pipe creates friction, which creates heat, which softens the glue. Once firmly embedded in the wood....er.....pipe, the glue hardens, creating a tenacious bond.
In wood, this makes the nail very difficult to pull out....a benefit. In a copper pipe, the glue serves as a sort of sealer, if you will, which keeps said pipe from leaking......until 8 or 9 months later when the nail itself rusts away enough to permit water to spray with surprising force from such a small hole.
This, of course, occurs in a cavity which has been sealed behind drywall, and so is not immediately apparent. What is apparent is the effect of several gallons of water on an acoustic tile ceiling below. It will need to be replaced.
Luckily, my client was home when the leak started, and had the presence of mind to shut off the water to the house. The plumber was able to find the leak quickly, and repair it this morning, so all is now well.
So, what's the lesson here? Look at the picture carefully. Do you see any metal kick plates on the bottom wood plate in front of those two pipes. Nope. Why not? As happens from time to time, that part of the job was overlooked. If you look even more carefully, you can see that the studs themselves were trimmed back in width (necessary to meet code requirements for hallway width).
The pipes, which prior to the stud trimming, sat comfortably in the middle of the wall, are now closer to the edge....within range of the nail gun. The plumber, whose work occurred elsewhere in the house, made sure to kick plate all of his work, as he always does. We, on the other hand, goofed, and didn't notice the hazard.
We'll get things put right, but you can be sure that this episode will prompt closer scrutiny in the future. They say you only really learn lessons that you pay for. After twenty five years of doing this, I oughtta' have a PhD by now!
