Pressure washing can remove the visible appearance of mold and mildew from a surface, but it does not kill the organism. Without a biocidal cleaning agent, the roots of the mold or mildew remain in the surface pores, and regrowth typically begins within weeks. Soft washing, which applies a sodium hypochlorite solution at low pressure, kills mold and mildew at the cellular level and produces results that last significantly longer.
The difference between removing and killing
Mold and mildew are living organisms that grow into porous surfaces. Pressure washing blasts the visible surface layer away but leaves behind hyphae, the root-like filaments that anchor the organism to the surface. Those root structures survive high-pressure rinsing and begin regenerating within weeks, especially in Fort Worth's humid conditions. Soft washing applies a biocidal solution that penetrates the surface, oxidizes the organism, and kills it before rinsing. The result looks the same immediately after cleaning, but stays clean far longer.
What North Texas mold and mildew look like
In the Fort Worth area, the most common surface growth types are:
- Green algae: Common on north-facing or shaded concrete, siding, and fences. Appears as a green or greenish-gray film. Slippery when wet.
- Black mildew/mold: Dark streaking on siding, wood, and painted surfaces. Common in shaded areas and where moisture pools.
- Gloeocapsa magma: The bacteria behind black roof streaks. Not technically mold but often misidentified as such. Spreads from shingle to shingle and feeds on limestone filler in asphalt shingles.
- Pink or orange staining: Often a bacterial growth (Serratia marcescens) or iron-related staining. Requires different treatment from standard mold.
Each type responds to soft washing with appropriate chemistry, but identifying what you are dealing with affects the mix and dwell time.
When mold is on different surfaces
The surface type matters as much as the organism type.
- Vinyl siding: Soft wash with SH solution. High-pressure washing risks driving moisture behind panels and creating interior mold problems.
- Brick: Low-to-medium pressure with appropriate chemistry. Efflorescence and organic growth often coexist on brick surfaces.
- Concrete: Higher pressure is acceptable here, often combined with a pre-treatment to lift organic growth.
- Roof shingles: Soft wash only. High pressure removes granules and shortens roof life.
- Wood decks and fences: Low pressure to avoid raising grain or splintering. Chemistry does the heavy lifting.
Does bleach alone work?
Applying diluted bleach with a garden sprayer will kill surface mold, but without pressure to rinse away dead material and a surfactant to help the solution cling and penetrate, the results are inconsistent. A professional soft wash system applies the solution at the right concentration, ensures adequate dwell time, and rinses at the right pressure for the surface. DIY bleach application often misses shaded areas, runs off vertical surfaces too quickly, or uses concentrations too low to kill the organism fully.
Fort Worth's climate keeps mold coming back
No cleaning is permanent. In North Texas, the conditions that created the mold in the first place, moisture, shade, pollen, and heat, do not go away. Proper soft washing kills what is present and extends the time before regrowth. Most homeowners find that a professional soft wash holds for 1 to 3 years depending on the surface and conditions.
CARE's approach to mold removal
CARE uses a sodium hypochlorite, surfactant, and water mix to treat mold and mildew on all applicable surfaces. Call (945) 275-8031 or visit our house washing page to schedule a soft wash that actually kills the problem.