Search for what mold removal costs and you will find a tidy per-square-foot number. Ask three Plano homeowners who have actually been through a remediation and you will hear three different totals. Both are honest. National planning ranges describe a broad middle, while a written quote describes one house, one water source, and one specific set of materials that has to be cut out and dried before the wall closes again.
What the Published Ranges Actually Cover
The most-cited figures are useful, but only if you know what they include. This Old House, in March 2026, puts mold remediation at $10 to $25 per square foot, averaging roughly $18. Fixr’s 2025 data runs the same work from $10 to $30 per square foot, sizes a typical whole job at $1,500 to $9,000 with a national average near $3,500, and puts a whole-house project at $10,000 to $30,000.
Smaller areas get bucketed by square footage. Using This Old House figures from March 2026, roughly 50 square feet lands at $500 to $1,250, 100 square feet at $1,000 to $2,500, 200 square feet at $2,000 to $5,000, and 500 square feet at $5,000 to $12,500. HomeAdvisor’s 2025 numbers for a licensed mold assessment — an invoice from a separate company, not the remediation crew — run $303 to $1,044, averaging near $670, with air-sample lab fees of $250 to $350 on top. The Texas Department of Licensing and Regulation charges a $25 notification fee for jobs at or above the 25-square-foot threshold.
Read those numbers as a shape rather than a promise. The per-square-foot spread is wide because a square foot of moldy drywall on a flat hallway wall is not the same as a square foot of ceiling above a finished living room. Containment size, how long drying equipment has to run, whether framing can be cleaned and saved or has to go, how accessible the cavity is, and whether cabinetry or flooring has to be pulled all move the total. An older, dated Plano-specific figure from HomeBlue in March 2022 listed $10 to $19 per square foot; treat it as a historical marker, not a current bid.
One structural detail explains a lot of quote shock. In Texas, the assessment, the written protocol, and the final clearance are handled by a licensed company that is not the company doing the removal. Two separate businesses, two separate invoices. A remediation quote on its own is never the full project cost, and any comparison that ignores the assessment side is incomplete.
Why a Plano Quote Lands Where It Lands
Plano’s housing stock explains more about pricing than any national average can. The median home here was built in 1993, and about 64 percent of the city’s units went up between 1970 and 1999. Roughly one in six predates 1980. Those older east and central neighborhoods often still have original cast-iron drain lines running beneath the slab, which is why a slab leak so frequently turns out to be the source when mold appears on a lower wall or along a baseboard with no obvious cause.
The geography compounds it. Nearly every Collin County home sits on a slab over shrink-swell Blackland clay, so there is no basement to flood and no crawl space to vent. Water from a slab leak or a slow supply-line weep travels sideways and upward into drywall, insulation, and the bottom plate of a wall, staying hidden until the paint blisters. Add DFW dew points that sit in the mid-60s for roughly five months of the year, and any damp cavity has ideal growing conditions.
West Plano tells a different story. Homes from the 1990s and 2000s are frequently two-story with the air handler in the attic, and many sat under the hail paths of June 2012 and April 2016. A roof or flashing failure wets attic decking and insulation, and a sweating or overflowing drain pan wets the platform beneath the air handler. When the February 2021 freeze burst pipes across the region, it added another category entirely — supply lines failing inside walls and ceilings while the house was empty.
Where the mold sits changes the job, and the quote follows. A bathroom ceiling stain from a failed exhaust fan is a contained, small-scope project. Attic growth around a roof leak means working in a hot, tight space with limited access. Growth inside an air handler or duct system raises a separate set of questions, and the EPA advises not running the system until it has been checked. Slab leak mold means the plumbing gets fixed first, or the growth returns.
Reading a Quote: What to Ask Before You Compare Totals
The 25-square-foot line is where cost conversations should start. Under 25 contiguous square feet of growth, you may clean it yourself or hire anyone. At or above that line, hired work in Texas requires licensed companies, a written protocol delivered at least a day before work begins, a work plan, TDLR notification, containment with negative air, a clearance assessment, and a signed Certificate of Mold Damage Remediation. Unlicensed work carries TDLR penalties of $2,000 to $5,000 per violation, and up to $5,000 a day under Occupations Code 51.302.
Ask every bidder for the same four things so the numbers are comparable: the scope in square footage and materials, whether drying equipment and the days it runs are included, whether rebuild of removed drywall is in the price or excluded, and who is performing the assessment and clearance. Ask for a start date and a target dry date. Drying, not demolition, usually sets the schedule.
Insurance deserves its own question. Texas policies generally cover a sudden and accidental discharge of water and generally do not cover a continuous leak. Most pay to remove mold only as part of repairing covered damage, and many cap or exclude mold remediation unless endorsed. Hidden losses should be reported within 30 days of discovery. Separately, once the job is finished, the TDI form MDR-1 certificate matters: under Insurance Code 544.303 an insurer may not underwrite against your home because of remediated mold damage shown on that certificate, and sellers must pass along every certificate from the prior five years. It is worth asking for it by name.
Permits are usually a non-issue for cutting out and cleaning mold-damaged material, but plumbing, foundation, HVAC, roof, and wall rebuilds do require them from city-registered contractors — confirm with Plano Building Inspections rather than assuming. Getting two or three written quotes from independent TDLR-licensed companies through mold removal plano is the fastest way to replace a national average with a number that reflects your actual walls, your actual water source, and your actual square footage — and to see whether the published range was a guide or a guess.
