Diamond Certified Company Spotlight Series: San Mateo County (Part 1)

We’ve all felt the joy of choosing a good company in <a href=https://www.diamondcertified.org/counties/san-mateo-county/ca/ target=_self>San Mateo County</a> and, unfortunately, the pain when we mistakenly choose a bad one. The problem is, every company claims to be good, yet despite these glowing claims some provide inconsistent quality while others are downright dishonest. We’ve solved this problem for you with Diamond Certified Resource. Only San Mateo County companies independently rated Highest in Quality and Helpful Expertise earn Diamond Certified. Our rigorous <a href=https://www.diamondcertified.org/ratings-process/ target=_self>rating and certification process</a> starts with the in-depth pass/fail rating of each company’s customer satisfaction, license and insurances. Most companies can’t pass our rating and earn Diamond Certified, and every Diamond Certified company must continue to deliver on its promises to you, the consumer. That’s why we conduct ongoing customer satisfaction research and credential-based ratings and monitor each company’s performance. Here’s a partial list of all the Diamond Certified companies that serve San Mateo County. Stay tuned next week for Part 2! <a href=https://www.diamondcertified.org/report/able-glass-company/ target=_self>Able Glass Company</a> Able Glass Company replaces windows and patio doors for homeowners in San Mateo and Santa Clara Counties. Second-generation owner Eric Holder continues his father’s legacy of quality work, and the company has earned recognition from the San Jose Mercury News with 16 consecutive “Best Window Installer” and “Best Door Installer” awards from 2010 to 2025. Able Glass Company also offers free in-home estimates and comprehensive home evaluations. <a href=https://www.diamondcertified.org/report/able-paving-grading-inc/ target=_self>Able Paving & Grading Inc.</a> Able Paving & Grading Inc. handles grading and paving work for residential and commercial clients in the Bay Area, covering everything from driveway and parking lot paving to large-scale earth moving, asphalt crack sealing, and sealcoating. The company prioritizes customer satisfaction with careful planning and onsite oversight, taking detailed notes at the start of each job and making sure technicians have the right materials so they never need to shortcut the work. <a href=https://www.diamondcertified.org/report/abstract-windows/ target=_self>Abstract Windows</a> Abstract Windows installs and sells windows and doors for residential and commercial clients in San Mateo County, San Francisco, and the Peninsula, working with everything from vinyl and fiberglass windows to French and patio doors. Owner Dimitar Georgiev credits the company's success to a meticulous, detail-oriented approach on every job and a focus on matching each installation properly to its opening. The family-owned company now runs a 12-person crew and averages 10 to 15 jobs a week. <a href=https://www.diamondcertified.org/report/airstars-corp/ target=_self>Airstars Corp.</a> Airstars Corp. provides HVAC services for residential and commercial clients in San Mateo, Santa Clara, Contra Costa, and Alameda Counties. In addition to installing, repairing, and maintaining heating and air conditioning systems from brands like Carrier and Trane, the company performs air flow and performance testing to confirm customers' systems run at peak efficiency. Owner Rafael Barrios says the company is focused on getting to know clients personally and solving comfort issues like uneven temperatures and poor airflow. <a href=https://www.diamondcertified.org/report/alexander-company/ target=_self>Alexander Company</a> Alexander Company installs replacement windows and doors for residential clients in San Mateo County and San Francisco. The company’s Burlingame showroom is stocked with vinyl, aluminum, wood, and fiberglass windows from manufacturers such as Simonton and Marvin. Brothers Jeff and John Alexander run the business as second-generation owners after taking over from their father, who founded the company in 1971. Because Alexander Company partners directly with major window manufacturers, it works as both dealer and contractor, letting customers handle sales and installation through a single company rather than coordinating separate vendors. <a href=https://www.diamondcertified.org/report/all-bay-insulation-hvac/ target=_self>All Bay Insulation & HVAC</a> All Bay Insulation & HVAC cleans attics and crawl spaces, installs HVAC systems, and handles other work aimed at improving indoor air quality and energy efficiency for residential and commercial clients in the Bay Area. The company also resolves crawl space moisture problems through encapsulation. Owner Noam Yaakobi points to the company's broad service lineup as a key advantage, since clients can meet all their HVAC, energy efficiency, and air quality needs through a single provider rather than hiring separate companies. <a href=https://www.diamondcertified.org/report/alternative-heating-air-conditioning-solutions-inc/ target=_self>Alternative Heating & Air Conditioning Solutions, Inc.</a> Alternative Heating & Air Conditioning Solutions, Inc. installs energy-efficient HVAC products for residential and commercial clients in San Mateo, Santa Clara, Alameda, and San Francisco Counties, with a focus on ductless split systems, zoning, and variable-speed and dual-source equipment that can heat and cool multiple rooms at once. General Manager Mike Rebholtz says the company works to stay current on energy-efficient technology, representing brands like Mitsubishi, Trane, and Carrier. Alternative HVAC Solutions is a participating contractor with BayREN, Peninsula Clean Energy, and TECH Clean California, and it sponsors community education events on net-zero and heat-pump technology throughout the Peninsula. <a href=https://www.diamondcertified.org/report/aren-electric-co-inc/ target=_self>Aren Electric Co., Inc.</a> Aren Electric Co., Inc. provides electrical repair and installation services for residential and commercial clients throughout the Peninsula, including wiring for appliances, lighting, and receptacles, electrical panel upgrades, and full safety inspections. Owner Gerry Reyes, a former U.S. Air Force electrical power production specialist, says his favorite part of the job is helping clients through stressful electrical hazards safely and professionally. The company equips its service trucks as fully stocked mobile warehouses, carrying thousands of electrical parts so technicians can resolve most jobs in a single visit. <a href=https://www.diamondcertified.org/report/awc/ target=_self>AWC</a> AWC cleans air ducts, dryer vents, windows, and gutters for residential and commercial clients in San Mateo, Santa Clara, and San Francisco Counties. Ron Frediani took over the family business that his father and uncle started in 1946 and has since expanded it into gutter cleaning, power washing, and air duct cleaning. Mr. Frediani says he treats every customer like family, taking the time to do thorough work rather than rushing through it. <a href=https://www.diamondcertified.org/report/bay-101-roofing-inc/ target=_self>Bay 101 Roofing, Inc.</a> Bay 101 Roofing, Inc. provides roofing services for residential clients in San Mateo and Santa Clara Counties, including reroofing, general repairs, cleaning, and new construction, plus maintenance on ventilation systems, sun tunnels, gutters, and downspouts. Owner Jose Ramirez has built the company around superior quality, attention to detail and customer service. Bay 101 Roofing employs its own certified installers rather than subcontractors, so training and accountability stay consistent from job to job. <a href=https://www.diamondcertified.org/report/bayhill-heat-air-inc/ target=_self>Bayhill Heat & Air, Inc.</a> Bayhill Heat & Air, Inc. installs, maintains, and repairs heating and cooling systems for residential clients in San Mateo, Santa Clara, Alameda and San Francisco Counties. Founder Ricardo Valderrama explains that focusing on HVAC allows for closer customer relationships, ensuring comfort and air quality. The company offers free estimates, 24/7 emergency service and a flexible warranty that extends even after the initial system installation. <a href=https://www.diamondcertified.org/report/best-construction/ target=_self>Best Construction</a> Best Construction provides design/build construction services for residential and commercial clients in San Mateo and Santa Clara Counties. With in-house capabilities for every phase of remodeling (including painting, plumbing and electrical work), the company is known for staying current with industry trends to provide high-quality service throughout the construction process. <a href=https://www.diamondcertified.org/report/bluebird-termite/ target=_self>Bluebird Termite</a> Bluebird Termite offers termite control services to residential and commercial clients in the Bay Area. The company uses localized treatment, fumigation, and soil and rod injection to eliminate drywood and subterranean termites, and it also performs structural repairs for termite and wood-destroying fungus damage. Owner John Chung built the company to make the process less intimidating for homeowners, focusing on clear communication and educating clients about their options during inspections. Mr. Chung says that once people understand what termite control actually involves, they feel more confident making decisions about their homes. <a href=https://www.diamondcertified.org/report/cal-auto-body/ target=_self>Cal Auto Body</a> Cal Auto Body provides body and collision repairs, accident-related mechanical work, and structural and frame repairs for all types of vehicles at its Colma facility. Owner Nana Sarkisian credits the company's success to a personalized approach that includes handling insurance issues, offering courtesy shuttle service, coordinating with rental car companies, and keeping customers updated throughout the repair. <a href=https://www.diamondcertified.org/report/carol-flynn-inc/ target=_self>Carol Flynn, Inc.</a> Carol Flynn, Inc. installs Carrier heating and air conditioning systems and services all types of HVAC equipment for residential and commercial clients throughout the Bay Area. The company has built its reputation over seven decades in business with NATE Certified technicians and a commitment to quality service at competitive pricing. President Marco Sandoval says the company is focused on transparency and customer education, offering free consultations and in-depth information to help clients make informed decisions. <a href=https://www.diamondcertified.org/report/closet-factory/ target=_self>Closet Factory</a> Closet Factory has been creating custom organization systems for closets, garages, home offices, pantries, laundry rooms, and specialty spaces like wine cellars and craft rooms for Greater Bay Area homeowners since 1983. The company designs, engineers, manufactures and installs in-house, which keeps quality tight and scheduling smoother. Free design consultations and digital tools help homeowners visualize finishes and accessories before they commit. <a href=https://www.diamondcertified.org/report/craftworks-painters-of-the-bay-area/ target=_self>CraftWorks Painters of the Bay Area</a> CraftWorks Painters of the Bay Area offers interior and exterior painting services to residential and commercial clients throughout the Peninsula, including full surface preparation and priming, power washing, staining and varnish application, and color consultation. Owners Steve and Norie Bonbright left the high-tech industry to start the business after spotting a need for a more customer-oriented painting company with reliable service and dependable crews. The company runs with a singular focus on building lasting relationships with customers, backed by clear communication between crews and clients throughout each project. <a href=https://www.diamondcertified.org/report/dansel-restoration-inc/ target=_self>Dansel Restoration Inc.</a> Dansel Restoration Inc. provides residential and commercial restoration services for properties affected by water, fire, or smoke damage. The company’s IICRC Certified technicians handle everything from structural drying and mold removal to sewage cleanup, offering 24-hour emergency response when disasters strike. Dansel Restoration also helps clients navigate the insurance process to ensure they feel supported during stressful situations. <a href=https://www.diamondcertified.org/report/dean-knecht-painting-inc/ target=_self>Dean Knecht Painting, Inc.</a> Dean Knecht Painting, Inc. offers interior and exterior painting to clients in San Mateo County and San Francisco, specializing in faux finishes and sponging and ragging techniques that add depth and texture. Owner Dean Knecht is a sixth-generation painter who started working for his father at age 15 before eventually starting his own business. Mr. Knecht says the company strip-peels wood the traditional way, with a heat gun, for a smoother and longer-lasting result. <a href=https://www.diamondcertified.org/report/degree-hvac-inc/ target=_self>Degree HVAC, Inc.</a> Degree HVAC, Inc. provides HVAC and plumbing services for residential, commercial, and industrial clients throughout San Mateo County. Owner Rick Lazzarini says the company's customer-oriented approach centers on making homes as comfortable as possible. Degree HVAC belongs to the Green Building Alliance and the Sheet Metal and Air Conditioning Contractors' National Association, and customers note the team's responsiveness and ability to sort out complex HVAC systems. <a href=https://www.diamondcertified.org/report/design-miter-tile/ target=_self>Design Miter Tile</a> Design Miter Tile provides a full range of remodeling services for homeowners throughout the Bay Area, handling everything from kitchen and bathroom projects to entire home remodels. As a general contractor, the company manages every phase of the process, from design to completion. Owner Daniel Zaragoza attributes the company’s success to transparent communication and a focus on quality craftsmanship. <a href=https://www.diamondcertified.org/report/discover-plumbing-rooter/ target=_self>Discover Plumbing & Rooter</a> Discover Plumbing & Rooter offers a wide range of plumbing services to residential and commercial clients in San Mateo County and San Francisco, handling everything from full sewer line replacements to basic fixture repairs and installations. Owner Faren Reyes credits the company's success to customer-oriented practices like free estimates and only performing repairs that genuinely improve a customer's plumbing system. <a href=https://www.diamondcertified.org/report/duggans-serra-mortuary/ target=_self>Duggan’s Serra Mortuary</a> Duggan’s Serra Mortuary has served Bay Area families for generations, combining a long history with deeply personal, family-owned care. The multilingual staff supports families across cultures and faiths with traditional and cremation services, and the facility includes private chapels, reception areas, and practical conveniences like ample parking. The team also offers preplanning support through “My Funeral, My Way®,” which helps families make clear decisions with less stress later. <a href=https://www.diamondcertified.org/report/edge-roofing/ target=_self>Edge Roofing</a> Edge Roofing installs and repairs roofing systems for residential and commercial clients throughout the Bay Area. The company has the training and equipment to handle asphalt, wood shingle, TPO, and modified bitumen roofs, plus roof inspections and seamless aluminum gutter installation. Owner William Young built the company around client relationships and streamlined project delivery. Mr. Young stays closely involved in quality control, keeping a site lead reporting back to him even on days he isn't walking the job himself. <a href=https://www.diamondcertified.org/report/el-gato-painting-restoration-inc/ target=_self>El Gato Painting & Restoration Inc.</a> El Gato Painting & Restoration Inc. provides interior and exterior painting services for residential and commercial clients throughout the South Bay and Tri-Valley, along with drywall patching, cosmetic dry rot repairs, stucco patching and deck staining. Owner Ken Slosarik says the company sprays and back rolls every job, which improves adhesion, coverage, and longevity. Its technicians attend weekly training and safety meetings to stay current on products and techniques. <a href=https://www.diamondcertified.org/report/elite-pro-home-cleaning/ target=_self>Elite Pro Home Cleaning</a> Elite Pro Home Cleaning has been cleaning homes and offices in San Mateo and Santa Clara Counties for more than 20 years, offering weekly, biweekly, monthly, and one-time cleanings. Owner Jennifer Young launched the business in 2003 as a franchise after leaving a corporate career. The company uses Green Seal Certified products, brings all its own supplies, and works in two-person teams. Team leaders need at least four years of tenure with the company, which helps crews get to know a home and tailor the cleaning to each customer's preferences over time. <a href=https://www.diamondcertified.org/report/engineered-soil-repairs-inc/ target=_self>Engineered Soil Repairs, Inc.</a> Engineered Soil Repairs, Inc. solves complex soil and foundation problems throughout Northern California, handling landslide repairs, creek bed stabilization, underpinning, releveling, retaining walls and drainage systems. The company’s in-house engineers assess issues, develop repair plans, manage permits and inspections, and keep the work coordinated under one roof. Crews bring deep field experience, and foremen and superintendents stay actively involved so projects keep moving with strong oversight. <a href=https://www.diamondcertified.org/report/first-lock-security-technologies/ target=_self>First Lock & Security Technologies</a> First Lock & Security Technologies provides a variety of locksmith services for residential and commercial clients throughout the Silicon Valley. From high-security and smart locks to master key systems, the company offers professional installation, repair, and rekeying services. Founder Gary Lekan emphasizes a commitment to craftsmanship, professionalism, and attention to detail on every project. <a href=https://www.diamondcertified.org/report/freedom-solar-inc/ target=_self>Freedom Solar, Inc.</a> Freedom Solar, Inc. designs, builds, and installs solar power and battery storage systems for residential and commercial clients in the Greater Bay Area. The company specializes in both new installations and system removals for roof replacements or major remodels. President Rich Moore says Freedom Solar helps clients reduce utility costs while supporting the environment, emphasizing its commitment to high-quality products and excellent customer service before and after the installation. <a href=https://www.diamondcertified.org/report/garage-door-experts-repair-installation-llc/ target=_self>Garage Door Experts Repair & Installation, LLC</a> Garage Door Experts Repair & Installation, LLC installs, repairs, and maintains garage doors for residential clients in San Mateo, San Francisco, Santa Clara, and Alameda Counties, handling everything from hinge and spring repairs to full door replacements and opener installations. Owner Omr Tamimi credits the company's success to a focus on customer service and accessibility. Technicians document every job with before-and-after photos, which the team reviews at weekly meetings to share insights and keep improving their process. <a href=https://www.diamondcertified.org/report/generation-builders-inc/ target=_self>Generation Builders Inc.</a> Generation Builders Inc. provides construction services for residential and commercial clients in San Mateo, San Francisco and Santa Clara Counties, including kitchen and bathroom remodeling, custom home construction and ADUs. The company manages each project with an emphasis on honesty, reliability, communication and quality control. Owner Leonardo Da Silva and his team keep clients informed and involved while conducting regular inspections and maintaining strict oversight to ensure each job meets industry standards, stays within scope, and is completed on schedule. <a href=https://www.diamondcertified.org/report/great-wall-termite-control/ target=_self>Great Wall Termite Control</a> Great Wall Termite Control provides termite services for residential, commercial, and industrial clients in San Mateo, Santa Clara, San Francisco, and Alameda Counties. The company uses localized, soil, fumigation and preventive treatments to control the three termite types most common in the Bay Area. Owner Chester Hiu credits much of its success to a customer-oriented approach: inspectors evaluate each property, ask questions, and tailor recommendations to what each client actually needs rather than pushing a one-size-fits-all treatment. <a href=https://www.diamondcertified.org/report/gruber-painting/ target=_self>Gruber Painting</a> Gruber Painting provides interior and exterior painting for residential and commercial clients in San Mateo, Santa Clara, and Alameda Counties, along with cosmetic dry rot repair, stucco patching, epoxy floor coating, drywall patching, and deck staining. Owner Joel Gruber started the company in 2009 as a one-person operation after choosing painting over his other seasonal job as a ski lift operator, and he has since grown it to six crews. Mr. Gruber says taking care of employees has been key to maintaining quality as the business has grown, since well-supported crew members are more likely to take good care of customers. <a href=https://www.diamondcertified.org/report/handy-bay-plumbing/ target=_self>Handy Bay Plumbing</a> Handy Bay Plumbing provides a full range of plumbing services for residential and commercial clients in San Mateo and Santa Clara Counties, including installation, maintenance, and repair of plumbing systems; sewer line replacement; leak detection; water heater repair and installation; and backflow testing. Owner Andres Tellez says he gives clients as much information as possible on every visit so they can make informed decisions, and he avoids pushing unnecessary repairs or replacements just to increase the bill.