Drain Cleaning in Houston, TX

Nearly every Houston house sits on a slab foundation, with drain pipes buried in the soil beneath it. Homes built before about 1975 usually have cast iron under the slab, and after fifty or more years that iron has rusted, scaled and sometimes cracked. When cast iron fails under a slab, the fix may mean tunneling or cutting through the floor.

Houston's gumbo clay is famous among builders. It swells when wet and shrinks when dry, and slabs move with it. That movement can crack pipes under the house and pull apart joints in the lateral running to the street.

Inner Loop neighborhoods such as the Heights, Montrose, Bellaire's edges, Riverside Terrace and the Third Ward have homes from the 1910s through the 1950s, some on pier-and-beam foundations with clay or cast iron laterals under live oaks that are a century old.

Postwar suburbs inside and just outside the Beltway, like Meyerland, Sharpstown, Spring Branch and Westbury, were built in the 1950s through the 1970s with cast iron drains and clay laterals. Many have been through at least one flood.

Newer subdivisions farther out, in Kingwood, Clear Lake, west Houston and along the Grand Parkway, have PVC drains. Calls there are mostly grease, wipes and the occasional toy or construction leftover.

Houston Public Works operates the city's wastewater system, one of the largest in the country. The homeowner owns the service line from the house to the city's main or tap. Many suburban areas are served by municipal utility districts, known as MUDs, which run their own sewer systems.

Hurricane season, June through November, and spring storms can dump inches of rain in hours, overloading city mains and pushing sewage back into low drains. Homes that flood may have silt and debris in their lines afterward.

Long summer droughts dry the clay and shift slabs, cracking old cast iron and opening lateral joints. The rare hard freeze, like February 2021, can burst exposed pipes and stop drains in unheated spaces.

Houston homes built from the 1950s into the mid-1970s almost always have cast iron drains running beneath the slab. Cast iron lasts a long time, but in Houston's damp soil it rusts from the inside out, building rough scale that catches paper and grease. Eventually the bottom of the pipe can rot through, letting water wash out the soil under the slab. A camera inspection shows whether descaling, lining or a reroute makes sense. Don't wait until the floor starts cracking.

Houston's clay soil holds water like a sponge. In wet seasons it swells and lifts the slab, and in long droughts it shrinks and lets the slab drop. That seasonal heave stresses every pipe under the house. Cracked fittings, separated joints and bellies in the lateral often show up after a hot, dry summer. Watering the foundation evenly during droughts helps protect both the slab and the pipes.

The Heights, Montrose, Woodland Heights and other Inner Loop neighborhoods have bungalows and cottages from the early 1900s, many on pier-and-beam foundations. Their laterals are often clay running under huge live oaks and pecans, and roots are routine. Pier-and-beam homes make under-house plumbing easier to reach than a slab, but the yard lateral is just as vulnerable to roots.

Neighborhoods along Brays Bayou and other bayous have flooded repeatedly, most notably during Harvey in 2017. After a flood, silt, debris and damaged pipe can linger in drains for months. Many homes have been raised or rebuilt; some still connect to old laterals. A camera inspection after any flood shows what's left in the line and whether the pipe was damaged.

When a big storm drops several inches of rain in an hour, Houston's mains can fill and push sewage back toward homes. The lowest drain in the house, often a downstairs shower or a floor drain, is where it shows up first. A backwater valve on the lateral lets wastewater flow out but stops it from coming back. If your home has had a storm backup, ask about installing one.

In August, after weeks without rain, a family in a 1964 ranch home in Spring Branch notices the hall bath toilet gurgling and the tub draining slowly. The plumber clears the main from the front cleanout, but the camera shows heavy scale and a crack in the cast iron under the slab, likely from the clay shrinking. The family gets quotes for lining versus rerouting the drain outside the foundation.

Houston loves a big gathering, from crawfish boils in spring to Thanksgiving fry-ups. Pouring boil water, oil or grease into a sink or toilet is a fast way to block a line. Let oil cool, put it in a sealed container and throw it away. Strain crawfish boil water outside away from the house, not into a drain.

Large parts of greater Houston, especially in the suburbs, get sewer service from municipal utility districts. Each MUD maintains its own mains and lift stations. If several neighbors have backups at once, call your MUD; the problem may be a failed lift station or a blocked main rather than your lateral.

Houston rarely freezes hard, but when it does, homes aren't built for it. In February 2021, pipes burst across the city. Drains in exterior walls, garages and attics can freeze too. During a hard freeze, keep cabinets open and let faucets drip.

Give your neighborhood and the home's age, whether it's on a slab or pier-and-beam, and whether the house has flooded. Mention big trees near the sewer path and whether the trouble started during heavy rain or after a long dry spell. If you're in a MUD, say so.