Orangeburg is a sewer pipe made of wood-pulp fiber bonded with coal-tar pitch, used in the U.S. from the late 1800s through the 1970s before PVC and ABS replaced it. Over time it softens, blisters and flattens into an oval under the weight of the soil, which leads to backups and root intrusion. A sewer camera inspection is the only way to know whether a home built before the mid-1970s still has it, and whether it is still round enough to line or needs replacing.
What is Orangeburg pipe?
Orangeburg, also sold as bituminous fiber pipe, was made from layers of wood-pulp fiber pressed together and saturated with coal-tar pitch. It was light, cheap and easy to cut, which made it popular for sewer laterals during the post-war building boom. It was used through the 1970s, when plastic pipe took over (history and construction).
Which homes around Denver might have it?
Any home whose original sewer line went in before the mid-1970s could have Orangeburg somewhere between the house and the street, unless the line has already been replaced. That covers a lot of older Denver neighborhoods and established parts of Aurora and the suburbs. It is less likely in newer Douglas County construction around Parker and Castle Rock, which was built after plastic pipe became standard. Age is only a clue; plenty of older homes have clay or cast iron instead, and some lines are a mix of materials from past repairs.
How does Orangeburg pipe fail?
| Failure | What it looks like on camera | What you notice |
|---|---|---|
| Deformation | Round pipe flattened into an oval | Slow main drain, recurring clogs |
| Blistering | Bubbles and flakes peeling off the wall | Debris snags and builds into blockages |
| Root intrusion | Roots through softened walls and joints | Clogs that return every growing season |
| Collapse | Pipe caved in, soil in the line | Backups, wet spots or a sinking area in the yard |
The soft walls are the core problem. Front Range clay soils swell and shrink with moisture, and that movement, plus the weight of the soil above, slowly squeezes the pipe out of round.
Can Orangeburg pipe be lined, or does it have to be replaced?
It depends on its shape. Lining needs a pipe that is still round enough to rebuild from the inside. If the camera shows the Orangeburg section has only light blistering and holds its shape, it may be a candidate for trenchless lining after careful cleaning. Once it has flattened, blistered heavily or collapsed, there is nothing sound left to bond to, and the right answer is excavation and replacement with modern pipe. We will show you the footage and explain which side of that line your pipe is on.
Should you check for Orangeburg before buying a house?
Yes, if the home was built before the mid-1970s. A pre-purchase sewer scope shows the pipe material, its shape and any root intrusion before you close, which is when a replacement cost is still a negotiating point. Our homebuyer's guide to sewer scopes covers what to ask for, and a sewer camera inspection gives you the footage to take to your agent.
With 25 years of scoping lines around the metro, we have learned not to guess a pipe's material from the age of the house. The camera tells us. When we do find Orangeburg, we show you its shape on screen and give you the honest call: line it if it is still round, replace it if it is not, and never sell a coating to a pipe that cannot hold it.
What should you do next?
If you own or are buying an older home with a slow main drain, call (303) 476-3160 or get your free quote. Related reading: tree roots in your sewer line and 7 signs your sewer line is failing.
Frequently asked questions
How do I know if my house has Orangeburg pipe?
The only reliable way is a sewer camera inspection. Orangeburg looks dark and fibrous on camera and often shows blistering or an oval shape. You may also see it at an exposed cleanout. A house built before the mid-1970s is a candidate, but many homes that age have clay or cast iron instead.
How long does Orangeburg pipe last?
It varies with soil, load and moisture, and many original Orangeburg lines have already failed or been replaced. Because production ended in the 1970s, any Orangeburg still in service is close to 50 years old or older, so it is worth inspecting even if it is not causing problems yet.
Is Orangeburg pipe a problem when selling a house?
It can be. Many buyers in the Denver market order a sewer scope, and finding Orangeburg often leads to a request for a repair or a price reduction. Scoping before you list lets you decide whether to replace it, price it in, or disclose it on your terms.
Can tree roots get into Orangeburg pipe?
Yes, and easily. The fiber walls soften with age, and roots exploit both the walls and the joints. Root intrusion in Orangeburg often speeds up deformation, so a line that needs root cleaning regularly should be checked on camera for its overall condition.