San Antonio
Slab Leak Repair and Replacement in San Antonio, TX
For slab leak repair and replacement in San Antonio, start here. San Antonio’s ground is a patchwork of clay and shallow limestone, the water is very hard, and most homes are on slabs. A local crew can pinpoint the leak without tearing up the floor first.
Answered 24 hours a day, every day.
Clay and limestone, often on the same lot
San Antonio sits where the Blackland clay of the east meets the limestone of the Edwards Plateau to the northwest. Much of the south and east has dark, expansive clay that swells and shrinks with moisture. The north and west has thin soil over limestone. Many lots have both, with clay pockets over rock.
On clay, a slab rides wet and dry cycles. On rock, lines can rest on hard points. In either case the common result is wear on the outside of a pipe over many years, usually at bends and where a line passes through a footing. This is background on the area and not a finding about any house.
Very hard water and copper
Water in the San Antonio area is among the hardest in the state. Mineral scale builds up inside supply lines, and in copper plumbing with pinhole leaks that keep returning, hard water is one thing a technician weighs. It is never the sole cause and says nothing about whether a particular house will leak. See hard water and copper leaks.
Tell us how much it changed.
From 1920s bungalows to new subdivisions
Closest to downtown, the housing dates to the early 1900s through the 1940s, and a lot of it sits on piers. After the war, slab ranches spread outward in every direction. The north, west and northeast filled in between the 1960s and 1980s. Since the 1990s, big PEX-plumbed subdivisions have extended the city far to the north and northwest.
Copper is common under slabs poured in the 1960s to 1980s. Houses finished between the late 1970s and mid-1990s can have polybutylene instead. Only a technician on site can say which one a house has.
Pier-and-beam and older houses
Under a raised floor there is a crawlspace instead of concrete, so a leaking supply line can generally be reached from underneath. Older houses often gained a concrete-floored addition later. Mention which rooms are which when you call.
Describe the signs you have seen.
Locating the leak
Work starts by closing off the hot and cold sides to see which one is losing pressure. Acoustic listening gear then follows the floor above the suspect line, and a thermal camera may show heat tracking under tile or wood. The aim is a small search area before anything is cut, although a precise spot is not always possible. See how slab leaks are found.
What happens after the leak is found
Choices usually include a spot repair in the slab, a new line run above it, lining the pipe where appropriate, or repiping if several lines are failing. The decision depends on leak location, how many leaks the house has had, the pipe material and the floor covering above. None is right for every house. Water drying belongs to restoration firms and flooring to flooring contractors.
A local crew explains what happens next.
What you can do today
Stop all water use in the house and check the meter. A moving dial means water is getting out somewhere on the lot. The water meter leak check page explains the steps. When water is coming up, close the main valve if it is safe to reach, move people, pets and valuables away, and call. Keep away from outlets and appliances near standing water. For any gas smell, go outside and call the gas utility and emergency services.
We connect you with a crew near you.
Is it a slab leak?
Signs in a San Antonio house
- SIGN 01
Warm spot on the floor
In San Antonio, a patch that stays warm in shade and with the heating off can follow a hot-water line. A local crew covering Bexar County can walk you through the next step.
- SIGN 02
Water bill jumped
A bill that rises month after month while the household stays the same in San Antonio. Ask a crew in San Antonio what this means for an older copper-plumbed house like yours.
- SIGN 03
Running water sound
A faint trickle that stops only when the main is closed on limestone and hard water in Bexar County.
- SIGN 04
Damp or lifting floor
Wet carpet at an edge, cupped wood or hollow-sounding tile across Bexar County.
- SIGN 05
Water heater never rests
Gas or power use that creeps up with no change in routine on rocky limestone ground.
- SIGN 06
Meter moving, fixtures off
A dial that keeps turning after every tap is closed in 1960s-80s homes.
Eight areas of San Antonio, by ZIP code
San Antonio has more than 60 ZIP codes. We group them into eight areas by geography, and each area has its own page.
Downtown & the Inner Core
6 ZIP codes: 78204, 78205, 78212, 78215, 78284, 78285.
Alamo Heights & North Central
6 ZIP codes: 78201, 78209, 78213, 78216, 78231, 78232.
Northeast San Antonio
5 ZIP codes: 78217, 78218, 78233, 78239, 78247.
East Side & Southeast San Antonio
12 ZIP codes: 78202, 78203, 78206, 78208, 78210, 78219, 78220, 78222, 78235, 78244, 78263, 78264.
South & Southwest San Antonio
9 ZIP codes: 78211, 78214, 78221, 78223, 78224, 78225, 78242, 78243, 78252.
West & Westside San Antonio
10 ZIP codes: 78207, 78226, 78227, 78228, 78237, 78238, 78240, 78241, 78245, 78251.
Northwest San Antonio & the Medical Center
9 ZIP codes: 78229, 78230, 78249, 78250, 78253, 78254, 78255, 78256, 78257.
Far North San Antonio & Stone Oak
6 ZIP codes: 78248, 78258, 78259, 78260, 78261, 78266.
Service area and nearby cities
Converse · Universal City · Helotes · Boerne · Schertz · Cibolo · New Braunfels · Bulverde
Questions we hear from San Antonio
Clay in some areas, limestone in others, very hard water, and many 1960s to 1980s slabs with copper underneath each contribute. A newer house can still leak at a fitting.
It varies. Expansive clay covers most of the south and east, while thin soil over limestone is typical in the north and west. Some lots have both.
Technicians treat it as one factor among several when pinhole leaks keep coming back in copper. It does not predict a leak in any given home.
Not beneath the main floor, but a room added on concrete can.
No, a leak is a plumbing issue. A foundation contractor handles foundation concerns.
A meter reading and a technician’s assessment before closing can show if water is escaping.
Lines are isolated and pressure tested, then acoustic listening and sometimes thermal imaging narrow down where it is.
In some houses a new line above the slab means the floor stays closed. It depends on the layout.
The whole city. Each of the eight area pages below covers a group of ZIP codes.
Slab leak repair and replacement in San Antonio
Phone us and a San Antonio crew will take it from there.
Straight answers on the phone.