Signs of Foundation Problems: Is Your Houston Foundation Sinking?

Common warning signs of a sinking or shifting foundation

A Houston foundation contractor interviewed by KPRC listed these signs of foundation movement (KPRC Click2Houston, Sept 18 2026, news report, checked 2026-10-13):

• Soil separating from the foundation, sometimes leaving a gap you can fit a hand into
• New diagonal cracks near doors or windows, including cracks above doors and at door frames
• Cracks in brick, exterior siding, tile or interior walls
• Doors that stick or don't close properly, and uneven gaps around doors
• Separation between bricks or other building materials
• Uneven or cracked floors

A Houston engineering group's guidelines list more symptoms: windows that stick or won't close, separations where brick veneer meets window and door frames, cracks and ridges on interior walls and ceilings, out-of-square door frames, out-of-level countertops, and sloping floors. They also note that not all of this damage is caused by foundation movement (Foundation Performance Association, FPA-SC-13-0 guidelines, checked 2026-10-13).

Is my foundation sinking or settling?

"Sinking" isn't an engineering term, but engineers do describe downward movement. The Foundation Performance Association defines subsidence as downward movement of the supporting soil "due to the withdrawal of moisture." It says this normally happens in clay soils and is often caused by soil drying out from trees or other large plants. The opposite is heave: upward movement, usually when water is added to dry expansive clay (Foundation Performance Association, FPA-SC-13-0, checked 2026-10-13). In Houston's clay, a house can move both ways with the wet and dry seasons. FPA's monitoring guide says movement can be "cyclical," following wet and dry seasons, or non-cyclical, and that a foundation should be monitored for at least a year to tell which (FPA-SC-12-0, Guidelines for Evaluating Foundation Performance by Monitoring, 2006, checked 2026-10-13).

Cracks in walls and ceilings

FPA's guidelines list cracks and ridges on interior walls and ceilings among possible signs of foundation movement (Foundation Performance Association, FPA-SC-13-0, checked 2026-10-13). But FPA has a separate paper on damage that's "often mistakenly attributed to foundation movement." Its examples include (FPA-SC-03-1, Distress Phenomena Often Mistakenly Attributed to Foundation Movement, 2004, checked 2026-10-13):

• Sags and cracks in drywall ceilings.
• Cracks or buckling at the top of walls that hold up sloping roofs. FPA ties these to roof framing, such as missing collar ties or an overloaded attic.
• Cracks along vaulted or gambrel ceilings, usually on exterior walls.
• Vertical cracks running the full height of a brick wall with the same width top to bottom, usually near the middle of the wall or near openings. FPA links these to the brick expanding and shrinking with heat and to missing or blocked expansion joints.
• Cracks in brick above long openings such as garage doors, which FPA links to an undersized or overloaded lintel (the beam over the opening).
• Surface shrinkage cracks in concrete as it cures.

So a crack's location and pattern can point to causes other than the foundation. Only someone who sees it in person can tell you which it is.

Doors and windows that stick

FPA calls doors or windows that stick, leak, won't close or won't latch, and doors that swing open or shut on their own ("ghost doors"), "Functional" distress. It puts noticeable floor slopes, wall tilts and tilted countertops in the same group (FPA-SC-12-0, Guidelines for Evaluating Foundation Performance by Monitoring, 2006, checked 2026-10-13). Sticking doors can have other causes too, which is another reason to get an in-person look.

What causes a foundation to sink or heave in Houston

• Clay soil. It absorbs water and expands when wet, then shrinks and cracks when dry. That cycle can create uneven support under a home (KPRC Click2Houston, Sept 18 2026, news report, checked 2026-10-13).
• Dry spells. KPRC reported a very dry six-week stretch in August–September 2026 (KPRC Click2Houston, Sept 18 2026, news report, checked 2026-10-13).
• Trees. The contractor in that story said a large oak can use up to 100 gallons of water a day (KPRC Click2Houston, Sept 18 2026, news report, checked 2026-10-13).
• Plumbing leaks. Houston engineers in the Foundation Performance Association list moisture changes from broken sewer or water pipes under the slab among the reasons shallow foundation repairs can fail (FPA-RC-01-0, Post Foundation Repair Performance, 2004, checked 2026-10-13).
• Soil type varies by area. One buyer's guide describes Beaumont clay across much of south, southwest, east and central Houston (Texas Inspector foundation book for buyers, published by a Houston home-inspection company, checked 2026-10-13).

Is a crack serious?

No photo or web page can tell you for sure. Here's how Houston engineers sort it out. FPA groups damage into three kinds (FPA-SC-12-0, Guidelines for Evaluating Foundation Performance by Monitoring, 2006, checked 2026-10-13):

• Architectural: cosmetic damage from minor separations in walls, floors, ceilings and paving.
• Functional: damage that affects how the house works, like sticking doors and windows or noticeable floor slopes.
• Structural: damage affecting the stability of the building, such as separations or distortions in studs, columns, beams or the foundation, so that a member "may no longer support the intended design load."

FPA also says this about cracks that keep coming back. When separations have been repaired "and the separations reoccur in the same or adjacent locations, this typically indicates continuing movement in the same direction, not cyclical movement" (FPA-SC-12-0, Guidelines for Evaluating Foundation Performance by Monitoring, 2006, checked 2026-10-13). A patched crack that reopens in the same spot is worth a professional look.

We don't give crack-width rules here, because none of the engineering sources we use give width limits for homeowners. For an independent opinion, an engineer's evaluation is the way to find out (see Foundation inspection). Non-structural crack repair is the cheap end of foundation work: Angi lists Houston crack repair at $600–$3,200 (Angi Houston cost data, page updated Oct 10 2025, published by Angi, a contractor-referral marketplace, checked 2026-10-13). For full repair prices, see Foundation repair cost in Houston.

What you can do now

• Take dated photos of cracks. Engineering guidelines note that photos can later help show whether changes have occurred (Foundation Performance Association, FPA-SC-13-0 guidelines, checked 2026-10-13).
• During dry spells, water the soil around the foundation evenly. KPRC's story describes using a soaker hose (KPRC Click2Houston, Sept 18 2026, news report, checked 2026-10-13). Follow local watering rules and avoid standing water (same source).

Root barriers, drainage and your foundation

Trees and leaks are among the causes listed above, and trees and water show up again and again in Houston foundation guidance. The Foundation Performance Association's maintenance guide says trees in or near a foundation's footprint, whether removed or planted during construction, "cause the majority of foundation problems requiring repair in this area." It also lists leaking pools, plumbing lines and drains, dripping faucets and air-conditioning condensate lines, and "misdirected water from clogged and broken gutters and downspouts" as causes of local wet spots that can lead to uneven movement on expansive soils, and says these should be fixed as soon as possible (Foundation Performance Association, FPA-SC-07-0, 2003, checked 2026-10-13).

What a root barrier is

A root barrier is a trench near the foundation filled with a barrier of concrete, polyethylene, chemically treated mesh or a similar material, meant to stop roots from growing under the slab and drawing out moisture. The association says most are 48 inches deep or less (Foundation Performance Association, FPA-RC-01-0, 2004, checked 2026-10-13).

What it isn't

The same document is clear that "maintenance systems should not be considered a repair," even though they can help a foundation perform better. It lists ways barriers can fall short:

• Roots can grow under a barrier that isn't deep enough, or over one with soil piled on top.
• Chemical barriers "will eventually become ineffective after ten years."
• Thin plastic sheeting can be punctured during installation.
• Cutting roots that already reach under the house can lead to local heave as the soil regains moisture, or to settlement if large roots decay.
• With a solid barrier, a leak between the barrier and the slab can trap water; the document names plumbing, sprinklers, downspouts and poor drainage as sources (same source).

Drainage habits that help

FPA-RC-01-0 also covers moisture barriers and says owners should watch for moisture or ponding water next to the foundation (same source). From both documents, the practical list is short: keep gutters and downspouts clear and pointed away from the house, fix plumbing, pool and condensate leaks promptly, and watch for standing water along the slab. If you're thinking about a root barrier near a mature tree, ask whoever proposes it how deep it will go, what it's made of, and what happens to the roots it cuts.

What about French drains?

A French drain is a buried drainage system. The Foundation Performance Association's design guide describes French drains as "subsurface drainage systems that are used around the perimeter of a foundation to remove free water in the subsoil," usually a 4-inch or larger perforated PVC pipe covered with sand and gravel and sloped to an outlet, which must connect to a working storm-drain outfall (FPA-SC-01-0 Foundation Design Options, 2004, checked 2026-10-13). The same guide lists real drawbacks for Houston-type soil. It says French drains are "not very effective in expansive clay soils" because the clay's permeability is so low; that a drain that isn't draining well can put moisture back into the soil around the foundation; that one placed too close can erode soil and lead to settlement; and that they need maintenance but are hard to monitor. It notes they are commonly used when a lot is too flat to grade properly (same source). The association's maintenance guide adds that surface grading comes first: water should drain away from the foundation and not pond against it, with the ground sloped two to five percent (FPA-SC-07-0, 2003, checked 2026-10-13). If someone proposes a French drain, ask where it will discharge, how far it sits from the slab, and why grading alone won't do.

How SteadyHomeHouston helps

SteadyHomeHouston publishes free guides on Houston foundation repair and will be paid by contractors for referrals once quote requests open. We don't inspect, repair or level homes. Quote requests are coming soon.

Related: SteadyHomeHouston home · Pier and beam foundation repair · Foundation repair cost · House leveling · Foundation inspection