Moldy Grout: Surface or Symptom?
We meter-test first, so you pay for the cure — not guesses.
Black shower grout has two completely different causes with two completely different price tags. Surface mildew — ugly, shallow, dry wall behind — loses to regrouting or deep-clean-and-seal for hundreds. A wet wall cavity — grout regrowing black within weeks, musty smell, soft spots — needs opening and rebuilding for thousands. Bleach can't tell them apart. Our moisture meter can, in about ninety seconds, free, at every Cromwell assessment.
Cromwell notes
Builder-grade tub-shower combos from the 80s and 90s dominate: one-piece surrounds, plastic trim, grout-free but ugly. Homeowners keep the tub footprint and gain everything by tiling the walls properly. Cromwell's 80s subdivisions are all hitting surround age at once — the same yellowed unit in fifty houses on one street. Bring us the black grout and the smell; we bring the meter and the truth — including when the truth costs less than you feared.
- Free moisture mapping. Readings at tub line, corners, valves, niche — shown to you.
- Surface mildew path. Regrout or clean-and-seal; hundreds, one day, done.
- Wet-wall path. Targeted opening, dry, treat, rebuild on proper substrate.
- Fan check included. Dead exhaust fans cause half of recurring 'mold' — we test airflow.
- No scare tactics. Readings and photos, not horror stories. Ever.
Beating Cromwell shower mold
Grout systems we install across Cromwell — matched to tile, water and habits.
Flexible, dense, mold-resistant joints.
Stain-proof; the forever option.
Uniform color + stain shield.
Invisible protection, reapplied.
Common questions
Bleach whitens surface mildew but can't reach grout roots or wall cavities, and its water feeds regrowth. Recurring black within weeks means the problem is behind the tile.
Pin and pinless readings at the tub line, corners, valves and niche — ninety seconds, non-destructive, results shown to you on the spot. Free.
Surface: clean-and-seal ($250–$600) or regrout ($450–$2,000). Wet wall: targeted rebuild priced with photos, typically low thousands. The meter decides, not the sales pitch.
Mostly allergenic, occasionally worse for sensitive people — but the wall rot it signals is the real expense. Fix the moisture path and both problems end.