Cast Iron, Galvanized and Orangeburg: Pipes in Older Puget Sound Homes

The era that built these neighborhoods

Bremerton's population exploded during the Second World War as the shipyard ramped up, and the housing that followed through the 1950s and 60s in East Bremerton, Manette, Port Orchard, Manchester, and the older districts of Tacoma was built with what was standard then: cast iron for the drains under the house, galvanized steel for the water lines, and whatever the local supplier carried for the sewer lateral in the yard, which in some developments was Orangeburg.

That housing is now sixty to eighty years old. Much of it is well built and well loved, and a lot of it still has the original pipe. If you own a home from that period and no one has told you the plumbing was replaced, assume it was not until you see it yourself.

Cast iron drains: how they age and how they fail

Cast iron is heavy, quiet, and nearly immune to roots when it stays in the crawlspace. Its enemy is its own interior. Sewer gas is mildly acidic, and over decades it eats the inside of the pipe, especially along the bottom of horizontal runs where waste sits. The wall thins, scale builds up in flakes called tuberculation, and eventually a channel rusts through along the bottom. From the outside the pipe looks fine. From the inside, on camera, it looks like a riverbed.

Symptoms arrive gradually. Drains slow because the rough interior catches paper and grease. Cleaning helps for a while, and each cleaning scrapes off scale and exposes fresh metal. Then one day there is a damp spot under the house, or a toilet flange that has rusted away from the pipe, or a sewer smell in the crawlspace that turns out to be a hairline split in a horizontal run.

We see cast iron that is still serviceable at seventy years, and cast iron that failed at forty in a wet crawlspace. A camera pass tells the difference. Scale that can be descaled and a sound wall means the pipe has life left; a bottom channel rusted through means it is time.

Galvanized water lines: pressure first, leaks later

Galvanized steel water pipe is steel with a zinc coating meant to stop rust. The zinc wears off from the inside over a few decades, and the steel underneath corrodes. Rust scale builds inward until a 3/4 inch pipe has a 1/4 inch opening. That is why the first complaint in a galvanized house is never a leak; it is a shower that loses pressure when the kitchen faucet opens, or hot water that takes forever because the hot side corrodes fastest.

Brown or rusty water after the house sits idle is the next sign, along with faucet aerators that clog with grit every few weeks. By the time pinhole leaks appear at threaded joints, usually in the crawlspace or where pipe passes through a wall, the system is at the end. Patching one joint on a galvanized line tends to disturb the next one.

A galvanized house also often has galvanized drain branches, 1-1/2 and 2 inch lines from sinks and tubs, which clog the same way the water lines close up. A kitchen line with a pencil-sized opening left in it is a common find.

Orangeburg: the pipe that was never meant to last

Orangeburg is the trade name for bituminized fiber pipe: wood pulp pressed with coal tar pitch into a pipe. It was cheap and light, and it was used for sewer laterals from roughly the 1940s into the early 1970s, including in developments around Kitsap and Pierce County. Its rated life was never long, and most of it has outlived that by decades.

It fails by losing its shape. Soil pressure flattens the round pipe into an oval, the top blisters and delaminates, and roots enter at the seams with ease. On camera it is unmistakable: a flattened, dark, fibrous tunnel with bubbles on the ceiling. A cable can tear through it, and hydro jetting can strip the inner layers, so once we see Orangeburg we stop cleaning and start talking about replacement.

There is no maintenance plan for Orangeburg. If your lateral is made of it, it is a replacement waiting for a date, and the only decision is whether you pick the date or a backup does.

How to identify what you have

Most of this is visible in a crawlspace, a utility room, or at the exposed pipe near the water heater. A flashlight and a few minutes answers more than you would expect.

• Cast iron drain: dark gray or black, heavy, with hub-and-spigot joints or no-hub couplings; a magnet sticks; rings dull when tapped
• Galvanized water pipe: dull gray to silver, threaded fittings, a magnet sticks; often with a white or rusty crust at joints
• Copper water pipe: reddish or green-tinged, soldered joints, no magnet attraction
• PEX: flexible plastic tubing, usually red, blue or white, with crimp or expansion fittings
• ABS drain: black plastic with glued joints; PVC drain: white plastic
• Orangeburg: only visible in the yard during excavation or on camera; looks like dark, fibrous, flattened pipe
• Clay or concrete sewer: short sections with bell joints, seen on camera as light-colored with visible joints every few feet

Replacement, piece by piece or all at once

Cast iron under the house is replaced with ABS or PVC. In a crawlspace we cut out the old iron, hang new plastic on proper supports with the right slope, and tie it into the fixtures above and the sewer below. A full crawlspace drain repipe on a typical rambler is a few days of work. Where a cast iron stack runs inside a wall, we often leave the vertical and replace the horizontals, since verticals corrode far less.

Galvanized water lines are replaced with PEX, or copper where a customer prefers it. A whole-house repipe runs new lines from the main shutoff to every fixture, abandons the old steel in place, and usually includes a new main shutoff valve and often a pressure reducing valve if the house never had one. Most of our galvanized-to-PEX repipes in Port Orchard and Bremerton ramblers take two to three days with water restored each evening.

Orangeburg and failed clay in the yard are replaced by excavation with new PVC and new cleanouts. We do not offer trenchless pipe bursting; we dig, which on most lots is a one- to two-day job and leaves you with a pipe you can camera from a cleanout any time.

Mistakes that make old pipe worse

Joining copper directly to galvanized steel sets up galvanic corrosion, and the galvanized side rots out at the joint in a few years. A dielectric union or a brass fitting between them stops it. We find a lot of DIY water heater swaps where this was missed.

Chemical drain cleaners on cast iron or galvanized drains accelerate corrosion, and on a pipe already thinned to a sliver they can finish it. Using a cable with too large a cutter in corroded cast iron can punch through the wall. And pouring a new patio or driveway over an Orangeburg lateral guarantees you will be cutting that concrete later.

The best thing you can do with old pipe is know its condition. A camera pass on the drains and a look at the exposed water lines, done once, lets you plan replacement on your schedule instead of during a flood in the crawlspace.