Copper pipe comes in three wall thicknesses — K, L, and M — and the letter is stamped on the pipe. The thickness decides where each type is used and how long it lasts.
The type K
Type K has the thickest wall and is used for underground service and high-pressure lines, and it is the most durable and expensive.
The type L
Type L is the standard for most home supply lines, balancing strength and cost, and it is a common choice for repipes.
The type M
Type M has the thinnest wall and is used for above-ground interior lines where cost matters, and it is more prone to pinholes over time.
The reading
The type is printed along the pipe, and knowing it helps predict how the line is aging. freezing winters put stress on exposed lines, and many older homes still have aging galvanized pipes In Naperville, thin type M lines are often the first to leak.
The pinhole
Thin type M copper is the most prone to pinhole leaks over time. Knowing the type in your walls helps predict when a repipe is coming.
The call
Know the pipe in your walls. Call 888-217-3585 and Naperville Plumbing Experts will match you with a Naperville pro.
Plumbing in Naperville: what to know
In Naperville, freezing winters put stress on exposed lines, and many older homes still have aging galvanized pipes. Pros in our network know the local quirks and bring the right parts on the first visit.
Across DuPage County — from Lisle, Warrenville and Bolingbrook to ZIP codes like 60540, 60565, 60564 — homeowners deal with the same kinds of issues. The tips above apply locally, and when a job goes beyond a quick fix, a vetted local pro is only a call away.
Need a hand in Naperville?
If a plumbing issue is beyond a quick fix, don't wait for it to get worse. Call 888-217-3585 and Naperville Plumbing Experts will match you with a vetted local pro — usually within minutes. Learn more about plumbing help in Naperville.