Clean Mold in a Basement or on Concrete

Why do basements get mold?

Basements sit against soil, have less airflow and often hold finished materials that absorb moisture. Window wells, grading, plumbing and sump pump failures can all let water in.

How do you remove mold from concrete?

Concrete is hard but porous. Mold usually grows on dust, dirt and finishes on the surface, and EPA guidance for hard surfaces is to scrub with detergent and water and dry completely. A white crust on concrete is usually efflorescence, a mineral deposit, which is not mold but signals moisture.

What about mold in basement carpet?

EPA guidance notes that absorbent or porous materials such as carpet may have to be thrown away if they become moldy. The EPA also advises drying water-damaged carpet within 24 to 48 hours.

How do you remove mold from basement walls?

Bare concrete or block can often be cleaned. Drywall, paneling and insulation on those walls that are moldy or wet are porous and typically removed so the wall can dry.

How do you find where the water is coming from?

Window wells that fill or drain poorly
Grading that slopes toward the foundation
Cracks or joints that leak after rain or snowmelt
Plumbing, water heaters and washing machine hoses
A sump pump that fails during a storm
Humid air condensing on cool concrete in summer

When should you call a professional for basement mold?

When the area is larger than about 10 square feet, when finished materials need to come out or after a flood. See what affects mold removal cost for what shapes an estimate.

Next steps and related help

If you would rather have a professional handle it, these are the services that apply:

Emergency Basement Mold Removal in Littleton, CO: Remediation for finished and unfinished basements, walkouts and window wells.
Emergency Concrete Mold Removal in Littleton, CO: Mold on concrete floors, foundation walls, block and garage slabs.
Emergency Carpet Mold Removal in Littleton, CO: Removal of mold-affected carpet and pad, with cleaning and drying of the floor below.

Keep reading:

We help homeowners in Littleton, Southeast Littleton and Centennial, Columbine, Columbine Valley and Bow Mar, Ken Caryl, Highlands Ranch, Roxborough. Call (303) 555-0142 or request a free estimate, or go back to the ZoneGuard home page to see everything we do. We do mold remediation only, so any testing or clearance sampling is done by an independent assessor.

Frequently asked questions

How do I clean mold in a basement?

Fix the water entry, scrub hard surfaces with detergent and water, dry completely and remove porous materials that are moldy or stayed wet.

How do I remove mold from concrete?

Scrub with detergent and water and dry completely. Recurring growth means moisture is moving through the concrete.

Is white powder on concrete walls mold?

It is usually efflorescence, a mineral deposit left by moisture, not mold, but it means water is present.

How do I remove mold behind basement walls?

The wall has to be opened to see the extent. Damaged drywall and insulation are removed and the cause of the moisture fixed.

How to Clean Mold in a Basement or on Concrete