There Could Be a ‘Ticking Time Bomb’ Hiding in Plain Sight in That House You Want To Buy

First-time homebuyers are dishing out $3,000 to $5,000 or more on unexpected repairs in their first year, according to Angi.

But whether you’re a first-time buyer or in the market for another home, knowing what to look for—before you close—may save you a great deal of cash and hassle down the road.

Of all the systems in a home, the plumbing system is often one of the most expensive surprises buyers encounter.

By familiarizing yourself with what plumbing issues to look for and what you can do to spot them early on, you can avoid costly surprises and make more informed decisions during your house hunt.

Hidden plumbing issues that could cost you big time

There are a number of plumbing problems that may cost thousands of dollars to resolve—and unfortunately, they might not be immediately apparent during a walkthrough.

The first one is sewer line damage.

That's the one that shows up a couple months after closing, when the whole house backs up into the basement floor drain, and it's almost always the one nobody scoped. 

“Depending on how bad the damage is and how deep the line sits, what we see runs from around $3,000 for a spot repair up to $15,000 for a full replacement with street work involved,” says Morgan Buck, owner of Bluefrog Plumbing + Drain in Portland, OR.

Older, malfunctioning water heaters are next.

“A standard replacement usually lands somewhere around $1,500 to $3,000 installed, and tankless conversions cost more because you're generally doing gas and venting work at the same time,” Buck explains.

Galvanized supply pipes are another slow-moving but expensive issue. 

“These can corrode from the inside out, so pressure drops off over a few years and then a joint lets go inside a wall. Replacing the supply piping in a house runs from several thousand dollars into the high teens depending on the size of the house and how the plumbing is laid out,” Buck explains.

Slab leaks are also a common surprise concern.

“Locating one takes equipment, and repairing it can mean cutting into the floor of the house, so those start in the low thousands and climb from there depending on how much water got out before anyone noticed,” adds Buck.

How to spot plumbing red flags during a walkthrough

Fortunately, you don't have to be a plumber to catch plumbing issues when you’re touring a home for the first time.

Before closing, Buck recommends you run every faucet, shower, and toilet.

“Run several of them at once and watch what happens to the pressure. If it’s poor, there are likely issues,” Buck says.

Then, look under every sink with a flashlight for corrosion, staining, or a bucket somebody left sitting there.

Next, pay attention to the water heater. Read the build date off the water heater's data plate, and check the floor around it for rust or old water marks.

Don’t forget to ask what material the supply pipes and the sewer line are, and whether either one has ever been replaced.

Lastly, thoroughly read the seller's disclosure specifically for prior backups, leaks, water damage, and insurance claims.

When a sewer scope is worth it

A home inspection is worth having, but it won’t tell you everything as it’s solely a visual analysis of the property. 

“The inspector isn't running a camera down the sewer line or evaluating what's buried in the yard, which means some of the most expensive problems in the house never make it into the report,” says Buck.

If the house you’re interested in is 20 years old or older, a sewer scope is often worth the time and money.

“A camera run will show root intrusion, cracks, offsets at the joints, bellies where the line has settled, or a section that's already collapsed,” explains Buck.

Also, if the home has cast iron, Orangeburg, galvanized steel, or polybutylene pipes, which can be at greater risk for deterioration and other issues, a sewer scope makes sense.

“A scope is usually a couple hundred dollars. Sewer work is the kind of repair people take out a loan for,” Buck adds.

What plumbing issues are a deal-breaker?

According to Buck, most plumbing issues aren’t true deal-breakers—as long as you know the repair cost before you sign on the dotted line.

“Leaky faucets, running toilets, dated fixtures, a water heater with a couple of years left in it are all normal. Get a bid, ask for a credit, move on. Those repairs are predictable and the price range on them is narrow,” says Buck.

The ones that deserve real attention are anything involving the main systems: the sewer line, the supply piping through the whole house, a slab leak, and drainage that backs up more than once. 

“Those can turn into five-figure repairs, and the range on them is wide, which is the actual problem,” Buck explains.

Unfortunately, nobody can tell you what a sewer replacement costs by looking at a photo of the yard.

“Get an estimate before closing rather than a ballpark from someone who hasn't been out to the house. From there, you may request a repair credit or require the seller to take care of the issues before closing,” adds Buck.

Lastly, if you go the credit route, make sure the number is based on a bid from a contractor who actually looked at the house.