Diamond Mechanical LLC, C-20 HVAC Contractor in Brentwood, CA
Diamond Mechanical LLC operating as a limited liability holds an active California contractor license (CSLB #1134349), valid through Mar 31, 2027. First issued in 2025, the license has been on the CSLB roster for 1 year. It carries a single CSLB classification: C-20 — HVAC Contractor. Records show an active surety bond on file with Jet Insurance Company and active workers' compensation coverage from Great American Alliance Insurance Company. The business is based in Brentwood, in Contra Costa County, California.
- License Number
- 1134349
- Issued
- Mar 13, 2025
- Status
- CLEAR
- Expires
- Mar 31, 2027
- Entity
- Limited Liability
- Surety
- Jet Insurance Company
- Bond Number
- JT013238
- Effective
- Feb 6, 2025
- Status
- Active
- Coverage
- Workers' Compensation Insurance
- Carrier
- Great American Alliance Insurance Company
- Policy Number
- WCF29866300
- Effective
- Feb 17, 2026
- Expires
- Jan 17, 2027
Recently licensed: the CSLB license is active and in good standing, issued within the last 2 years.
An automated summary of public CSLB data, not a credit score, rating, or endorsement. How we determine this
Is Diamond Mechanical LLC licensed in California?
Yes. Diamond Mechanical LLC holds California Contractors State License Board license number 1134349, which is active and in good standing. The license was first issued on March 13, 2025. It is valid through March 31, 2027.
What does Diamond Mechanical LLC specialize in?
Diamond Mechanical LLC is licensed for one CSLB classification: C-20 HVAC Contractor.
Where is Diamond Mechanical LLC headquartered?
Diamond Mechanical LLC is headquartered at 2034 Thicket Pl, Brentwood, CA 94513, in Contra Costa County, California.
Does Diamond Mechanical LLC have an active surety bond on file with CSLB?
Yes. Diamond Mechanical LLC has an active California contractor surety bond filed with Jet Insurance Company.
Does Diamond Mechanical LLC carry workers' compensation coverage?
Yes. Diamond Mechanical LLC carries active workers' compensation coverage through Great American Alliance Insurance Company.
How do I verify Diamond Mechanical LLC's contractor license?
You can verify Diamond Mechanical LLC's license directly with the California Contractors State License Board at https://www.cslb.ca.gov/OnlineServices/CheckLicenseII/LicenseDetail.aspx?LicNum=1134349.
- Bond activeFeb 6, 2025
- License issuedMar 13, 2025
- WC coverage startsFeb 17, 2026
- WC expiresJan 17, 2027
- License expiresMar 31, 2027
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