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Find Mold & toxic material testers in Castro Valley

Avatar for Mold Test Company Central CA
Mold Test Company Central CA
4.5(
73
)

Serving Castro Valley, CA and surrounding areas

Approved

In business since 2015

Emergency services offered

Small jobs welcome

"The inspector was professional and thorough. The report was timely and the company's representative called me to explain the results of the test. I've emailed him to request clarifications and am awaiting his reply. The only negative thing is that after our telephone conversation he transferred me to a 3rd party company who markets mold removal services. The rep there tried to sell me his product. I didn't buy it yet."
Attic Ceiling
Drywall
Drywall
Insulation
Insulation

+66

Response time10 hrs
260 neighbors recently requested a quote
Recommended by87%of homeowners
Avatar for Environmental Science Services
Environmental Science Services
4.8(
35
)

Serving Castro Valley, CA and surrounding areas

Approved

In business since 1992

Free estimates

Emergency services offered

"Shane is very professional. I hired ESS because they offered indoor air quality tests for asbestos in addition to bulk sample tests. I also had an airborne mold test since they traveled to Santa Rosa, and the report was very thorough and tested for 27 types of mold spores including Stachybotrys (toxic black mold). I would recommend ESS to a friend seeking this service."
interior
IAQ
Clandestine Laboratory Investigation
Wipe Testing for Asbestos
Water Intrusion Mold Testing

+3

Response time8 hrs
4 neighbors recently requested a quote
Recommended by97%of homeowners
Avatar for Air Quality Testers
Air Quality Testers
5.0(
5
)

Serving Castro Valley, CA and surrounding areas

Approved

In business since 2020

Small jobs welcome

Credit card accepted

Breathe Easier with Expert Mold Inspections and Environmental Air Testing. At Air Quality Testers, we specialize in Certified Indoor Air Quality and Mold Testing Services. Our experienced professionals evaluate your air quality, detect mold, and provide personalized solutions. Schedule Your Test Today for a Healthier Home or Office: Tailored Advice and Simple Solutions for Clean Air. We safeguard your space with comprehensive air quality and mold testing, ensuring peace of mind for you and your family.\n\nOur focus is on those concerned about the air quality in their homes or workplaces. We stand out by offering certified indoor air quality testing and mold inspections, thorough air quality assessments, tailored recommendations for improvement, and cutting-edge technology to uncover hidden mold and evaluate air conditions.

Crawlspace hatch
Crawlspace
Storage Room
Response time2 days
Response rate97%
Avatar for Mold & Air Quality Consulting LLC
Mold & Air Quality Consulting LLC
1.0(
1
)

Serving Castro Valley, CA and surrounding areas

Approved

In business since 2019

Emergency services offered

Small jobs welcome

My name is Giovanni, and I represent Mold & Air Quality Consulting LLC. We specialize in offering a range of professional services to help ensure a safe and healthy environment, including:\n\n • Onsite mold assessment and evaluation inspections \n • Mold sampling \n • Air Quality Testing \n • Pre-remediation air testing \n • Post-remediation air testing At Mold & Air \n\nQuality Consulting LLC, we prioritize honesty, transparency, and integrity. If you are seeking a mold and air quality inspection company that values these principles, we are the ideal choice for you and your family. Our inspection services are straightforward and client-focused. Unlike others, we do not earn commissions on sales, nor do we use scare tactics to push remediation services. Our primary goal is to provide you with clear, unbiased information to help protect the health and safety of your home.\n\nBest regard,\nGiovanni Salmon\nMold & Air Quality Consulting LLC

Mold Inspection
Mold Inspection
Response time1 day
Response rate90%
Avatar for American Air Testing Inc
American Air Testing Inc
4.8(
12
)

Serving Castro Valley, CA and surrounding areas

In business since 2001

Free estimates

Warranties offered

"I suspected the presence of mold in our first floor due to an allergic reaction and a previous leak in the area.  John Riera and his son came, took moisture readings and air samples.  In addition, John was able to troubleshoot and provide other possible causes/solutions to the allergies.  He produced a detailed report with good advice.  The service is pricier than other mold inspection companies, but I like that there is no potential conflict as he does not do remediation, and that his expertise extends to other chemical contaminants."
Recommended by83%of homeowners
Avatar for Green Planet Mold & Restoration
Green Planet Mold & Restoration
5.0(
26
)

Serving Castro Valley, CA and surrounding areas

In business since 2003

Free estimates

Emergency services offered

"I could not have asked for a more positive experience! Jose is responsive, informative, flexible, and a great person! He set our expectations and followed them or reset them, thoroughly answered all of our questions, and communicated through email, phone calls, and text. He not only put us at ease, but also helped us with a Handyman to rebuild, figuring out our 3rd party post test company, and went above and beyond in supplying HEPA Filters and spraying our son's room! I highly recommend using Jose at Green Home Solutions for your mold testing and remediation. Definitely a "cut above!""
Recommended by100%of homeowners
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FAQs for mold & toxic material test projects in Castro Valley, CA

Some companies offer a no‑cost phone or video consultation that screens for red flags. If the discussion points to a real issue, the pro will recommend a paid on‑site inspection. The complimentary call clarifies whether you need full testing, but it isn’t a substitute for samples, lab work, or a written report. Always confirm what the free service covers before you schedule.

A standard inspection, which includes basic air and surface samples, takes an average of two hours. If the pro needs to probe hidden spaces, such as wall cavities or ductwork, plan on up to six hours. Extra time allows the inspector to reach tight areas, collect additional samples, and document findings. Lab analysis is a separate process and often adds several business days to the overall timeframe before you receive the full report.

Mold thrives where moisture lingers and air flow is poor. Common hotspots include bathroom walls, kitchen backsplashes, window sills, HVAC vents, fireplaces, crawl spaces, and enclosed attics. Check these areas regularly—especially after leaks or high‑humidity weather—to catch growth early and avoid costly repairs.

Unchecked mold can knock 20% to 37% off a home’s market value because buyers worry about hidden damage and health risks. Even after remediation, visible staining or a history of major moisture issues can still lower offers and prolong the time on the market. Addressing mold quickly protects both your property’s structural integrity and its resale appeal.

The Castro Valley, CA homeowners’ guide to mold & toxic material tests

From average costs to expert advice, get all the answers you need to get your job done.