Homeowner guide

How to Find a Slab Leak

Reading your own water meter, running an evaporation test on a pool, and knowing when a leak specialist beats calling a plumber first.

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The short version

What the show has actually said

A slab leak is the expensive kind of plumbing problem because nothing visible happens for a long time. The water bill climbs, a spot on the floor is warm, and water has been running under the house for weeks.

The leak episode with Jim of JC's Leak Detection is where to start, and it is the oldest episode on this page. It covers finding a leak under a slab, reading your own water meter to see whether anything is moving while the house is off, and the cases where a leak specialist is the right first call and a plumber is not. It also covers pools: standard evaporation in Houston is about an eighth of an inch, so a pool losing an inch is not evaporating, and an evaporation test with a bucket settles it in twenty four hours. The other thing that episode asks of every homeowner is to know where three things are before there is an emergency: the meter, the house shutoff and the sewer cleanout.

Ryan Burke covers the sewer side, including running a camera down the line and what a replacement costs. Eric Blanco of Dry Guys handles what a slow leak becomes, including a nail driven through a pipe inside a wall. The Notion sensor review and the Fisher family's flood stop device are the two ways to be told about water before a floor tells you.

5 episodes

The episodes behind this guide

That time we talked about leaks artwork
Ep 6Oct 23, 201853 min

That time we talked about leaks

In this episode Craig and Kevin interview Jim of JC’s Leak Detection. We discuss various times when it’s important to call a leak specialist instead of a plumber.

That time we talked about Plumbing artwork
Ep 24Feb 19, 20191 hr 0 min

That time we talked about Plumbing

In this episode Craig and Kevin interview Ryan Burke from Burke Family Plumbing. We felt this episode could’ve been a lot longer because there was so much to cover!

Notion Smart Home Review artwork
Ep 178Feb 9, 202248 min

Notion Smart Home Review

In this episode Craig and Kevin review the Notion Smart Home device. Craig received the device from his insurance company in exchange for a lowered premium.

Questions we get

Common questions

How do I check for a hidden leak myself?

Go and read the meter. On the leak detection episode the first test is to shut the water off at the house and watch whether the meter still moves, which tells you water is going somewhere. The same episode asks every homeowner to know where the meter, the house shutoff and the sewer cleanout are before anything goes wrong.

Is my pool leaking or just evaporating?

Run an evaporation test. Jim of JC's Leak Detection explained it on the leak episode: float a bucket of pool water, mark both levels, and after twenty four hours compare what the pool lost with what the bucket lost. He also gives the local number to sanity check against, which is that standard evaporation in Houston is about an eighth of an inch.

Should I call a plumber or a leak detection company?

It depends on whether anybody knows where the leak is. The leak episode covers the cases where a specialist finds it first and a plumber fixes it second, and the cases where calling a plumber straight away is the wrong order. Craig's screen on the phone is whether the company asks you questions before they come out.

Can a hidden leak turn into mold?

Frequently, and that is Eric Blanco's business. On the mold and water damage episode he covers slow leaks, a nail through a pipe, and what happens between the leak starting and anybody noticing. A leak sensor is the cheap intervention, which is why Craig's insurance company sent him a Notion kit in exchange for a lower premium.

There is a lot more where that came from.

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