What's actually causing this
Grout gets stained and discolored because it's porous and absorbs soap scum, mold, mildew, and mineral deposits. Unsealed grout absorbs stains much faster.
What you'll need
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Step-by-step fix
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1
Make a cleaning paste
Mix baking soda with just enough hydrogen peroxide to form a thick paste. Apply it directly to the grout lines. Let it sit for 5–10 minutes before scrubbing.
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2
Scrub the grout
Use a stiff-bristled grout brush or an old toothbrush. Scrub in small circular motions along each grout line. For floor grout, a drill attachment brush saves significant time.
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3
Rinse thoroughly
Wipe away the paste and residue with a damp cloth, then rinse with clean water. Leftover baking soda residue will leave a white haze if not fully rinsed.
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4
Tackle mold with targeted cleaner
For black mold in shower grout, spray undiluted white vinegar or a tile and grout mold spray. Let it sit 15 minutes before scrubbing. For persistent mold, oxygen bleach (not chlorine bleach) works on most grout types.
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5
Seal the grout
Once the grout is clean and fully dry (wait 24 hours), apply a penetrating grout sealer with an applicator brush. This fills the pores and makes the grout water-resistant. Re-seal once a year in high-traffic areas.
Professional cleaning services in Washington typically charge $200–600 for a standard home cleaning. Pressure washing runs $300–1,200 depending on surface area.
High humidity in Washington means mold and mildew prevention is an ongoing task, not a one-time clean. Bathrooms, kitchens, and basements need regular treatment.
Regular cleaning and maintenance frequency varies by Washington's climate and conditions.
DIY in Washington: DC's strict codes, historic preservation requirements, and high licensing standards restrict DIY repairs. Most homeowners must hire licensed professionals. Permits are expensive. Non-compliance costs are high.
- Grout is cracking, crumbling, or missing in sections — needs regrouting.
- Mold keeps coming back within days despite cleaning — may indicate moisture behind the tile.
- Tile itself is cracked or loose — a deeper substrate issue.
Let Uncle AI diagnose it first.
Describe the problem. Uncle AI asks the right questions and tells you exactly what's broken — and whether you should fix it yourself or call someone in Washington.
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