Pipes in walls can prove a minor disaster for homeowners when they pierce them with a power drill. The first sign is usually water spurting out, and this can be electrically dangerous too. After the scramble to find the water main, they have to wait for the pipe to drain down. What a mess this makes in a kitchen!
Plumbing Conventions & The Direction of Pipes
pipes in walls
Heating System: Hephaestos: CC 3.0
Runs of pipe generally follow horizontal and vertical lines. They have to, given that most plumbing joints are either straight or right-angled. This runs counter to the convention that the shortest distance between two points is a straight line. There is unfortunately always a possibility that a maverick plumber took a short cut across the middle of the wall.
The Most Likely Directions of Pipes in Walls
That said, most water pipes come directly down from the ceiling or up from the floor, to a point where they may branch out to the left or right, and subsequently up or down.
My first picture illustrates this principle in a basement. Water from the retrofit radiator in the second image probably comes from a boiler in the roof space.
To Approaches for Avoiding Pipes in Walls
pipes in walls
New Radiator: Jocelyn Durston: CC 2.0
The first method is the ‘educated guess’, although I cannot fully endorse this here. I would probably be tempted to drill a hole in the center of the wall diagonally to the right of the radiator though, depending on what is on the far side of the wall.
However, the only fail-safe way I know of avoiding pipes in walls is using a metal detector. I always experiment with ferrous and non-ferrous settings at various strengths. A quick ‘health warning’ before I go. A metal detector will not find electric wire in a plastic conduit. You need to find an electrician with test equipment.