Roy Bartholomew Sonora CA

Director of Engineering for On Guard Security Systems Inc.

About Me

In Modesto, California, Roy Bartholomew (Roy Bartholomew Sonora) is the Director of Engineering at On Guard Security Systems, Inc. Mr. Bartholomew was born and reared in the San Francisco Bay Area, the youngest of seven children born to French-speaking Cajun parents.

Roy Bartholomew is also the owner of By Referral Only Electric. After 35 years in engineering, he has amassed a specialized and in-demand skill set and beneficial relationships with local and national company owners.

Mr. Bartholomew's engineering, design work, and consulting services for Biodomes and other engineered ecosystems are well recognized in the engineering world, in addition to his full-time profession and entrepreneurial endeavours. Mr. Bartholomew currently resides in Northern California with his wife and children.

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Roy Bartholomew Sonora CA - Portfolio

Recent News

Electrical Issues
March 24, 2023

Homeowners’ Top 3 Electrical Issues

If you’re a homeowner, chances are you’ve had to deal with some electrical issues. These problems are a pain and can be hazardous. Surges happen when a lightning strike or other external force disrupts the flow of electricity. Lights Are Dim Dim lights are a common problem and may indicate that something is wrong with […]

March 22, 2023

Five Affordable Methods to Go From Fluorescent to LED Lighting

With their superior energy efficiency, LED lighting offers substantial savings. You can shave $200 or more off your annual electric bill by switching from fluorescent to LED. LEDs also offer several other benefits. For example, they can be dimmable and have various color temperatures to suit your space. They also have a longer lifespan than […]

3 Most Common Electrical Problems in Homes
February 23, 2023

3 Most Common Electrical Problems in Homes

Electrical problems can be frustrating and even dangerous whether your home is old or new. Here are 3 of the most common electrical issues that homeowners experience. A common problem is an appliance or other device tripping the circuit breaker, usually due to overloading it or using too much power. It could also be a […]

January 25, 2023

5 Questions You Should Ask Before Hiring An Electrician

If you need a licensed electrician to fix your electrical issues, you will want to know the right questions to ask before choosing one. This article will provide information on five critical questions you should ask before hiring a professional. Rewiring is the only way to fix an electrical problem The best way to tackle […]

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