Professional Building Maintenance and Construction Services Located in the San Francisco Bay Area
We specialize in construction cleaning at every phase of the project. From rough cleans to detailed finishes. Our team ensures your job site stays clean, safe, and professional throughout the build, and that it’s pristine and presentation-ready when the work is done.
Our final cleaning services are the finishing touch your project deserves. We handle detailed post-construction cleanups to ensure every surface is spotless, every corner is dust-free, and the entire site is move-in ready. It’s the last step before handing off a polished, professional space.
From daily porter services to full-scale janitorial operations, our facility maintenance solutions keep your spaces clean, safe, and operating at their best. We tailor our services to office buildings, retail centers, and other commercial environments—ensuring a consistently professional appearance for your business.
We offer comprehensive door and lock solutions—from simple replacements to advanced installations. Whether you’re upgrading to ADA-compliant panic hardware or enhancing security with smart access systems, our team ensures every entry point is safe, functional, and up to code.
Gold Standard Building Maintenance operates under CA Contractor License #743317, held through TNT Construction & Restoration, with Thor Michelsen serving as the company's Responsible Managing Officer (RMO). This licensing authorizes our team to perform a wide range of construction and plumbing work throughout California.
A B-license allows us to manage and perform projects involving two or more building trades—such as framing, carpentry, drywall, painting, or electrical work. This classification covers general construction and remodeling, ensuring we can oversee complete builds, tenant improvements, and coordinated repair projects from start to finish.
The C-36 classification authorizes us to handle all aspects of plumbing work, including water and gas piping, fixture installation, drainage systems, and plumbing line replacement or repair. This ensures full compliance and quality for projects involving water supply, waste disposal, or other fluid systems.
Gold Standard Building Maintenance is a family-owned company founded by brothers Mason and Thor Michelsen, born and raised in San Francisco. With deep local roots and a shared passion for craftsmanship, they lead with integrity, professionalism, and a dedication to doing every job right.
Mason brings over a decade of financial and operational experience, ensuring each project runs efficiently, transparently, and with long-term client trust. Thor, a skilled carpenter and licensed contractor, adds years of hands-on expertise across all phases of construction; from framing and finish work to complex site coordination ensuring every project is built to last.
Gold Standard operates under CA Contractor License #743317, held through TNT Construction & Restoration, with Thor Michelsen serving as the company’s Responsible Managing Officer (RMO). This license covers both B – General Building and C-36 – Plumbing classifications, authorizing a wide range of construction, maintenance, and renovation work across California.
A Legacy of Excellence
Their father, Thor Michelsen, brings over 40 years of hands-on experience in the construction industry
and nearly 30 years as a licensed general contractor. His career spans residential builds,
commercial renovations, and structural projects throughout the Bay Area. His craftsmanship, reliability,
and leadership continue to define the “Gold Standard” — a tradition built on hard work, skill,
and pride in every job completed.
Our Evolution
What began as a professional custodial and post-construction cleaning company has evolved into a full-service
construction and facility improvement provider. Today, Gold Standard delivers expertise across building
maintenance, tenant improvements, installations, and general construction. Combining precision, safety,
and care in every project.
Please fill out the form below to request a quote or ask a question.
