Mold in Walls & Drywall in Houston, TX

Clues that the problem is inside the wall

• A musty odor that is strongest near one wall, closet or cabinet base
• Paint that bubbles or peels, or drywall that feels soft when pressed
• Swollen or darkened baseboards, especially on slab floors next to a bathroom or kitchen
• A water stain under a window that grows after tropical downpours
• Staining on a ceiling or wall below the attic air handler

How water gets into Houston walls

Many Houston homes keep the air handler in the attic, and when its condensate line clogs, the drain pan can spill water that runs down inside an interior wall for weeks before anyone notices. Plumbing walls behind showers and sinks leak slowly. Heavy Gulf rain can push water past window flashing and brick veneer on exterior walls. After a flood, drywall soaks water upward well above the visible waterline, which is why the Houston Health Department inspected flooded homes after Hurricane Harvey for conditions such as mold in walls or floors. EPA's advice for flooded homes is to assume mold if materials could not be dried within 24 to 48 hours.

What a proper job looks like

1. Find and stop the water. Without this, new drywall will grow mold again.
2. Look inside. A mold assessment consultant uses moisture readings, a small inspection hole or a borescope to see how far the damage runs. EPA says sampling is usually unnecessary when mold is visible.
3. Write the protocol. Texas requires the consultant to give you a written protocol, at least one calendar day before work starts, listing the areas, quantities, containment and clearance criteria.
4. Remove and clean. A different company, one that holds a TDLR mold remediation contractor license, seals the area, cuts out wet drywall and insulation, cleans the studs and dries the cavity.
5. Check before closing. The consultant does a post-remediation assessment before new drywall goes up.

Can you open the wall yourself?

Texas lets homeowners clean mold in their own home, and EPA says a patch under about 10 square feet is usually manageable once the leak is fixed. Wall cavities are harder: the hidden side is often larger than the visible stain, and cutting into moldy drywall without containment spreads dust through the house. If you hire someone for the work, Texas law requires a TDLR mold license, and the company that writes the protocol cannot be the one that removes the mold.

Cost and paperwork

Angi's Houston cost data reports mold removal averaging $2,016, with most jobs between $863 and $3,329. Expect a separate fee for the assessment consultant, plus drywall, paint and trim if they are not in the remediation quote. Ask the contractor whether rebuilding needs a permit from the Houston Permitting Center. When the job passes, you should receive a Certificate of Mold Damage Remediation; keep it, since sellers must give buyers copies from the past five years.