
You’re worried about possible plumbing and foundation issues and think you might need hydrostatic pressure testing on your home. What are the best reasons to get a hydrostatic plumbing test? When is it going to benefit you the most to get hydrostatic testing done on your under-slab plumbing?
At Anchor Foundation Repair, we understand the close ties between plumbing and foundation issues. We may not be plumbing experts, but we know all about plumbing problems underneath a slab foundation. After 35+ years in business, we can share our under-slab plumbing knowledge and experience with you concerning hydrostatic testing.
This article will briefly explain hydrostatic testing and discuss the 6 reasons it will benefit you the most to get a hydrostatic pressure test done on your home. We will also go over what to do next based on the results of the test.
What Is a Hydrostatic Plumbing Pressure Test?

The term hydrostatic translates to “standing water” and involves watching the level of water when your pipes are full to see if it changes, which would indicate a leak in your plumbing system.
So, a hydrostatic plumbing test is a way to check and see if your plumbing drain line system is leaking or intact. First, your home drain system is isolated from the municipal sewer lines so that only your home is being checked. The test is then conducted by filling your drain lines all the way up with water to see if it holds that water or if any of it escapes the closed system.
The *pressure* in a hydrostatic pressure test is simply the extra pressure created by filling the drain lines completely full. This extra pressure slightly stresses the lines to locate even the smallest cracks in the drain system.
Top Times When Hydrostatic Testing Benefits You the Most
Now you’re like, “Well, why would I want to put this pressure on my plumbing lines? Seems like a bad idea . . .”
Ordinarily, you don’t want to put undue pressure on any system in your home. But when you’re trying to figure out if there’s a leaking drain line problem, then this is a non-invasive way to do it.

Hydrostatic testing benefits homeowners when it means you can either prevent, identify, or solve problems for your plumbing and home. Here are six practical reasons you might decide that a hydrostatic test is a good idea:
- You are having foundation repairs and want to prevent future issues
- You are having foundation repairs and your warranty policy requires it
- You have minor signs of foundation settlement near a bath, kitchen, or laundry area
- You have frequent plumbing issues like slow drains, gurgling, or backups
- You have occasional water seeping up through the foundation after a rain
- You want to confirm with insurance that a plumbing leak caused foundation problems
Don’t worry, now we will elaborate on these a little.
1. Having Foundation Repairs and Wanting to Prevent Future Issues
We know that under-slab plumbing leaks can cause foundation issues. We also know that sometimes the action of raising a home will inadvertently separate drain lines and cause leaks.
So why pay for foundation repairs and leave a situation under your home that could cause leaks again?
Having a hydrostatic test will verify that you don’t have under-slab plumbing leaks in a post-foundation repair situation. You can at least eliminate one potential source of future foundation settlement to prevent more issues from developing later.

2. Having Foundation Repairs and Your Warranty Requires the Test
Some foundation repair companies require you to have a hydrostatic plumbing test after the repairs. Otherwise, they won’t honor your warranty later.

This goes back to the reason listed above in item 1 about under-slab plumbing leaks causing foundation issues. A foundation repair company will only warranty the work if there are no leaks because they know leaks cause more problems.
So, for your warranty to be honored, they want to ensure that no leaks are present after the repairs. It’s in your best interest to get the hydrostatic test done, or else you could void your warranty.
Re-read your foundation repair contract to see if this is a requirement. Even if it’s not required, a hydrostatic test still might be a good idea regardless – see item 1.
3. Minor Signs of Settlement Near Water Source Areas

Having a hydrostatic test can confirm the cause of your foundation settlement. If you have under-slab leaks causing settlement near your bathroom, kitchen, or laundry areas, the hydrostatic test will help you understand why you are experiencing this foundation issue.
Understanding the root cause of your particular foundation settlement problem will help in getting any needed plumbing and foundation repairs done right AND minimize the chances of future problems.
4. Frequent Plumbing Issues like Slow Drains, Gurgling, or Backups

You might not be having foundation problems right now. You might just be having some drain line problems like recurring slow-draining fixtures, gurgling toilets or drains, or drain backups.
These kinds of plumbing problems can sometimes be because of under-slab plumbing leaks or they can also have other root causes too.
Conducting the hydrostatic plumbing test will either confirm that a leaking or broken drain line is the source of your issues or help rule out that issue. Then your plumber can continue to look for other causes.
5. Occasional Water Seeping Up Through the Foundation After Rain
If you have water seeping up through your foundation after it rains, you likely have an issue. The hydrostatic pressure test will help to isolate where the problem in your drain system is located and make sure that all the leaks or breaks get fixed.
When you have under-slab plumbing issues, it’s important to repair all breaks, separations, or cracks and not miss any leak sources. Otherwise, the seeping water problem keeps happening.
6. Confirm with Insurance That a Plumbing Leak Caused the Problems
Some insurance policies will either cover foundation problems caused by plumbing leaks or cover under-slab tunneling to reach plumbing leaks or both. If you suspect that you have foundation issues and/or under-slab plumbing leaks, it’s a good idea to get a hydrostatic test to see if that is the cause of either issue.
Insurance policies are complicated and all very different. We are certainly not insurance experts so we recommend checking with your insurance professional to check and see if anything could be covered by your policy.

Insurance Coverage for Foundation Issues
Insurance coverage for typical foundation problems is rare, but if your foundation problem is directly caused by under-slab leaks then coverage *could be possible* if it’s in your policy.
Part of proving an insurance case with under-slab leaks directly causing your foundation problem would involve hydrostatic testing to verify that you have a leak or leaks. So it could be very much in your best interest to conduct the hydrostatic pressure test to check for leaks if it means that insurance can help pay some of the foundation repair costs.
Insurance Coverage for Under-Slab Tunneling

Insurance can also *sometimes* cover the costs of under-slab tunneling to reach under-slab leaks. A policy doesn’t typically cover the cost of repairing the leak itself, just the cost of reaching it. Again, if it means that you can get help covering costs through insurance, the hydrostatic test will begin to prove you have an issue that could be covered.
What to Do After the Results of Your Hydrostatic Pressure Test
Ok, so let’s say you go ahead and get a hydrostatic test done, what do you do with the results? Did your house pass or fail the hydrostatic test? If your hydrostatic test reveals that you do not have any under-slab plumbing leaks, congratulations! You can remove the worry of leaking drain lines from your list and pursue other repairs.
If your hydrostatic test indicates that you DO have leaks, then more steps need to be taken by a plumber and/or other contractors to locate and ultimately fix the under-slab drain line problem:

- Isolate the leak point with further testing in small parts of the drain system
- Run a camera to pinpoint exact location to be repaired if desired
- Hire a contractor (like Anchor) to reach the leak with under-slab tunneling
Tunneling greatly benefits homeowners because the work stays underneath your home instead of breaking through the slab and trying to do it inside your house. You can carry on with life without plumbers, dirt, and a cracked open slab inside your home.
For more on the benefits of under-slab tunneling check out: What Is and Why Use Under-Slab Tunneling for Leaks Under a Foundation?
More Detail on How a Hydrostatic Plumbing Test is Done

Now that you know all about the times that it could benefit you to have a hydrostatic pressure test done, you want more details on how the process actually works.
At Anchor Foundation Repair, we understand the stress and anxiety that comes with overwhelming repair projects and offer empowering education to help you out. After 35+ years in business in the Brazos Valley, we want you to know as much about your home issues as you would like.
It’s the house you love and you deserve to be 100% in the know about all your home repair decisions. Check out this “What Is a Hydrostatic Pressure Test?” article for more details on the step-by-step process of conducting this kind of drain line test.