Under the house, stop 6 of 7

No crawlspace? What a slab house shows from outside

Slab house plumbing stays mostly hidden, so read what shows outside: no foundation vents, a concrete edge at the ground, and pipes rising to the wall. Your water line from the meter to the building is still yours on Columbia Water’s map¹. The walk here stops at the wall.

Stand at the corner of the house and walk the outside wall, looking low where the siding or brick meets the ground.

Updated November 4, 2026, Midlands House Walk

Pipe coming out of the ground to a tap on vinyl siding, concrete edge showing at ground level — A pipe rising from the ground to a tap at the wall of a slab house, with the concrete edge visible and vinyl siding above. AI-generated picture.

Louvered metal vent set in brick with a dark gap behind and grass below — A foundation vent in a brick wall, dark space behind. If your house has these, it has a crawlspace, not a slab. AI-generated picture.

Is it really a slab?

Look for: Walk all four sides. Vents or a hatch mean a crawlspace, even if you’ve always heard otherwise. A bare concrete edge with no openings points to a slab.
What it tells you: If you find vents or a hatch, the crawlspace hatch stop is the one for you. On a slab, your checks stay outside and at the meter.

Red lever on a brass valve fitted to copper rising from mulch into a brick wall — A brass ball valve with a red lever on a copper pipe rising from mulch into a brick wall. Yours may be nearby. AI-generated picture.

Where does the water come in?

Look for: Follow the line of the wall nearest the street. A pipe coming up from the ground, often with a valve, is where to look first.
What it tells you: Clemson lists near the foundation among common shutoff spots². Test it before you need it. Your house shutoff has more places to look if this wall shows nothing.

White screw-capped plastic pipe beside a red brick wall, mulch around it — A white plastic pipe with a screw cap beside a brick wall. Pipes like this are often a sewer cleanout. AI-generated picture.

Is there a cap near the wall?

Look for: Check the bed along the wall, near a bathroom or kitchen side of the house. Don’t take the cap off.
What it tells you: With no crawlspace, a cap like this is one of the few parts of your sewer line you can see. Finding the cleanout explains what it’s for.

In-ground meter box with its cover off, brass dial visible against wet soil — A brass meter with a round dial in an open box. This reading is one of the few checks a slab house owner gets. AI-generated picture.

Is the meter still moving?

Look for: Read the dial, use no water for 2 hours, and read it again³. Looking at the dial is fine. Leave the meter and its valve alone.
What it tells you: A change with everything off means water is going somewhere you can’t see. That tells you to call a plumber, and it doesn’t tell you where. The meter test walks through it.

What if you think something's wrong under the floor?

Note what you saw and the meter numbers, then ask who to call. This walk doesn’t go under a slab, and what happens beneath the floor isn’t something you can read from the yard.

Yours to do

Find the main shutoff and test it, as Clemson advises for any house before a freeze².
Run the 2-hour meter test once a year, and write the numbers down³.
Foam any pipe exposed at the wall. Pipe buried 12 inches should never freeze in South Carolina, but the bit above ground can⁴.

For a licensed pro

Finding a leak once the meter says there is one. That’s a plumber’s job, with their own tools.
Any cutting into a floor or slab.
Repairs on the yard line between the meter and the house, if you’re on Columbia Water, because the city can’t repair private lines¹.

Where this comes from

Keep walking (AI picture)Water or sewage under the house: what to do first