The plumbing that sits behind the walls and under the floors of your home is almost never seen, but that doesn't mean it should be neglected. Even in homes more than 30 years old, most pipes should last quite a long time. But, like anything else, they can begin to wear out and will eventually need to be replaced. Depending on how much of your plumbing system needs an overhaul and what materials you use, the job could be a small task or a major project. No matter what, it's always a good idea to leave advanced plumbing projects to the experts.
When to Replace
Pipes that are obviously damaged, leaking, or corrosive should be relatively easy to spot and need to be replaced as soon as possible. However, the average plumbing system in a home should last a long time. The typical lifespan of a household plumbing system depends on its exact function and the materials it's made from.
Supply lines are the main arteries for water entering a home, and are often made out of brass, copper, or galvanized steel. Since they are under constant pressure, they tend to cause more damage if they leak.
- Brass supply lines should last between 80 and 100 years.
- Copper supply lines should last between 70 and 80 years.
- Galvanized steel supply lines last between 80 and 100 years. However, galvanized steel pipes made prior to 1986 contain traces of lead, a toxic metal, and should be replaced if possible.
Drain lines are the pipes that take used water from sinks and toilets into the sewer system. They are usually made from either cast iron or polyvinyl chloride (PVC).
- Cast iron pipes should last between 80 and 100 years.
- PVC pipes should last between 25 and 40 years.
These lifespans are simply rough estimates. Well-maintained plumbing could last much longer, while poor maintenance or the presence of hard water could reduce the useful life of the pipes. To know when replacement may be in your future, keep an eye on exposed plumbing as much as possible. Leaks are the most obvious sign of trouble, but homeowners should also take note of any pipes that appear discolored, stained or warped. Consult a professional plumber when any of these warning signs appear.
Best Replacement Choices
If you need to replace some or all of your home's plumbing, work with your plumber to understand your options. A full replacement of a home's plumbing system is obviously the most expensive - the owner of a 1,500-square-foot, two-bathroom home can expect to pay between $4,000 and $10,000 for this project. However, total replacement isn't always necessary, and using certain methods or materials could reduce costs.
Copper
For decades, the "gold standard" for pipe material has been copper. This flexible, durable metal can be expected to last 80 years or more, and will not leech harmful chemicals into drinking water. But copper's longevity comes with some drawbacks. The most obvious is its high price, which can be as much as $285 per 100 feet and is rising with increased demand. And even though copper does not pollute water and can be recycled, its mining and manufacturing process releases a large amount of pollution. For this reason, the use of copper pipes may be restricted in places with particularly stringent building codes.
PVC
This type of plastic is widely used for drain pipes, while a similar material, CPVC, is suitable for drinking water. PVC and CPVC are relatively inexpensive at around $50 per 100 feet, and they are much easier to install than copper. On the other hand, these materials have roughly half the lifespan of copper. PVC manufacturing is also a major pollution source, and it cannot be recycled.
Cross-Linked Polyethylene (PEX)
A more modern choice for replacement plumbing is PEX, which edges out PVC in terms of cost and ease of installation. PEX costs around $30 per 100 feet, and can be snaked into walls or curved around corners. This makes PEX ideal for retrofitting. PEX is also more environmentally friendly than PVC or copper. It's certified for use in California, a state with some of the toughest green building codes in the United States.
Polypropylene Pipe (PP)
The most environmentally friendly of all pipe materials is considered to be PP. Unlike PEX, which may require potentially unsafe chemicals to bond joints together, PP can simply be fused together with heat. PP can also be recycled and has a longer lifespan than PVC or PEX. At around $110 per 100 feet, PP is cheaper than copper, although installation and repair might be more expensive due to the specialized tools and techniques involved.