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Robert Devengenzo is president of Devengenzo Landscaping & General Engineering Inc., a Diamond Certified company since 2013. He can be reached at (925) 405-6912 or byemail.

Robert Devengenzo

diamond certified contributor profile and expert article

Robert Devengenzo: Full Circle

By James Florence, Diamond Certified Resource Reporter

LAFAYETTE — After getting an early education in the construction field, Robert Devengenzo decided to switch gears and start a gardening business. However, as his business grew, he found himself incorporating more and more of his previous experience…until he eventually came full circle. “My dad built two or three of his own homes during his lifetime, and from the time I was 10 years old, he had me working alongside him,” he remembers. “After high school, I got into landscaping and ended up starting a gardening business with my wife, Marilyn. During the next few years, I acquired my landscape contractor’s license and brought on a few employees. It continued to grow from there—the more experience I had, the bigger the jobs became. It wasn’t long before I branched out from gardening and landscaping to doing drainage systems and general construction.”

Today, as owner of Devengenzo Landscaping and Engineering Inc., Robert continues to maintain a hands-on involvement with his company’s operations. “I enjoy meeting new clients, doing estimates and presenting our company to them. I also like to be out in the field, running crews and overseeing things. After all these years, those are still the aspects of the job I enjoy the most.”

Robert resides in Walnut Creek, which he considers an ideal location for someone in his line of work. “Between the affluent economy and the prevalence of older homes, there’s plenty of demand for our services in Contra Costa County. A lot of our work comes from homeowners who buy older homes and don’t know they have drainage issues. Also, with all the hills around here, there are a lot of challenges, which keeps things interesting.”

Outside of work, Robert enjoys spending time with his large family. “Marilyn and I have five kids, several of whom have worked for our business,” he says. “My oldest son worked for me for 12 years and is now a general engineering contractor, and my youngest is currently our lead carpenter. We also have 14 grandkids, ranging from age three to 25. Basically, there’s never a dull moment!”

In his life and career, Robert believes in doing things a certain way: the right way. “The main thing I believe, and the thing I impart to my employees, is if you’re going to do something, you have to do it right or not at all,” he affirms. “Other than my kids, I’ve had three guys who’ve worked for me in the past, and I schooled them well enough that they could get their licenses and be successful on their own. I take a lot of pride in that.”

When asked the first thing he’d do if he were to retire tomorrow, Robert says he’d transition to a more rural mode of life. “Marilyn and I did farming for about 14 years and enjoyed it very much, so I’d love to get back to doing that. We’d also like to do some more traveling—it’s been a long time since we’ve been out of the country.”

Ask Me Anything!

Q: If you could travel anywhere in the world, where would you go?
A: Italy, because that’s where my family heritage is based.

Q: What’s your favorite restaurant?
A: I have two: Il Fornaio and Fleming’s Prime Steakhouse & Wine Bar, both of which are in Walnut Creek.

Q: What’s your favorite holiday?
A: Christmas. In addition to my wife’s baking, I look forward to all the kids and grandkids coming over.

Q: If you could time travel, would you go to the past or the future?
A: The past. I love history, and I’ve always wanted to live in the Old West.

Q: Who’s your favorite movie cowboy?
A: Clint Eastwood.

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Understanding Two-Pipe Drainage Systems


LAFAYETTE — While often overlooked, drainage is nonetheless a vital functional aspect of any home. There are a few different ways to go about achieving proper drainage, but the most common method is installing a “two-pipe system.” A two-pipe drainage system… Read more

Expert Video Tip

Video: Understanding your Drainage System

Complete Video Transcription:

LAFAYETTE — Host, Sarah Rutan: When having a new drainage system installed on your property, it’s worthwhile to get an idea of how it functions. Today we’re… Read more

Jim Gardner is owner of Jim Gardner Construction Inc., a Diamond Certified company. He can be reached at (510) 254-5887 or by email.

Jim Gardner

diamond certified contributor profile and expert article

Jim Gardner: A Sound Structure

By James Florence, Diamond Certified Resource Reporter

OAKLAND — After more than 20 years doing structural work, Jim Gardner has established himself as an expert in his field. However, the foundation of his professional expertise didn’t form overnight; rather, it was something he built up gradually. “After college, I wasn’t sure what I wanted to do, so I worked a bunch of different jobs, including firefighter, swim instructor and river rafting guide,” he recounts. “When my mother moved to the Bay Area from Southern California and bought a house, I offered to fix it up for her. I’ve always been handy, but I’d never done any real construction work at that point, so I just dove in and learned as I went along.”

Jim enjoyed working on his mother’s house so much that when he was finished, he started his own handyman business. “While working as a handyman, I progressively took on new projects and expanded my skill set,” he says. “After spending a year or so working with a contractor, I got my own contractor’s license in 1983. In the mid-’90s, I did my first foundation project and fell in love with structural work, which is my specialty today. I liked the heavy duty aspect of it, with all the heavy machinery, but I also appreciated how critical a building’s structure is. After all, it’s what holds everything else up.”

Today, as owner of Jim Gardner Construction Inc., Jim says his favorite part of his job is solving problems. “I like taking on challenging projects and figuring out solutions. Sometimes I’ll be looking at a situation, scratching my head, and suddenly there’s this ‘A-ha’ moment and I see what’s needed. It’s very satisfying to find a solution to a problem and then implement it for the client.”

A resident of Piedmont (where he lives with his wife, Lisa, and their two daughters), Jim spends his time outside of work on a variety of pastimes. “I enjoy outdoor activities like camping, fishing and hiking, as well as traveling with my family. My daughters are both involved in sports, so we do a fair amount of traveling to out-of-town games and competitions. Speaking of sports, I’m a diehard Golden State Warriors fan—I never miss a game. And, of course, as a UC Berkeley alum, I also root for the Cal Berkeley football and basketball teams.”

When asked about a professional philosophy, Jim espouses the importance of communication. “Contractors have a reputation for being dishonest, but I think a lot of that stems from poor communication,” he explains. “When there’s confusion around the scope of the work and expectations are unclear, it can lead to a lot of problems. I try to avoid that by spending time communicating with my clients and making sure we’re all on the same page. I think that goes a long way toward securing a positive outcome.”

When asked the first thing he’d do if he were to retire tomorrow, Jim says he’d head for the hills. “It’s always been my dream to buy a place up in the mountains, so that would probably be my first priority. I’d also go on some trips and do some of the things I haven’t had much time for over the years.”

Ask Me Anything!

Q: What was your first job?
A: As a teenager, I had a summer job at the NASA Jet Propulsion Lab in Pasadena. I did model building for some of the space probes they were working on. It felt pretty cool having security clearance to get into a NASA facility.

Q: Are you a dog person or a cat person?
A: It’s funny, I’m kind of both. I used to be a cat person, but then we got a dog, so it’s hard for me to choose now.

Q: What’s your favorite local restaurant?
A: Scott’s Seafood Grill & Bar in Oakland.

Q: Do you collect anything?
A: I collect rocks and tools.

Q: If you could go anywhere on vacation, where would you go?
A: Either Tahiti or Fiji—basically, somewhere that has a beach and is far away.

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Solutions for Drainage Problems


OAKLAND — When it comes to drainage, most homeowners don’t realize there are two different types of water that need to be addressed: surface water and subterranean water (also known as groundwater). Furthermore, these two types of water each require specific solutions… Read more

Expert Video Tip

Video: Avoiding Drainage Problems

Complete Video Transcription:

OAKLAND — Host, Sarah Rutan: From your roof to your foundation, it’s important to have systems in place to ensure proper drainage and avoid related problems. Today we’re… Read more

Mark Corrallo is president of All Seasons Construction, a Diamond Certified company since 2007. He can be reached at (510) 652-2221 or by email.

Mark Corrallo

diamond certified contributor profile and expert article

Mark Corrallo: A Seasoned Career

By James Florence, Diamond Certified Resource Reporter

OAKLAND — When Mark Corrallo purchased a construction firm in 2007, he didn’t have any hands-on experience in the trades. However, given the tempestuous conditions he’d soon be navigating, the background he did have proved to be a far more valuable asset. “Prior to purchasing All Seasons Construction, I was a business broker, which means I facilitated the buying and selling of businesses,” he explains. “All Seasons Construction was one of the businesses that came across my desk, but after looking at it more closely, I decided to purchase it myself. I didn’t have any experience in the construction industry, but it looked like a good business opportunity, so I decided to take a shot at running my own company.”

In hindsight, Mark’s decision to purchase a construction business couldn’t have been more ill-timed: Within a year, the U.S. would slide into the worst economic recession it had seen since the Great Depression. However, while the downturn left many construction firms floundering in its wake, Mark’s business acumen helped him keep his company not just afloat but swimming forward. “By adapting to the economic conditions, I was able to keep my crews busy throughout the recession,” he says. “Since purchasing All Seasons Construction a decade ago, I’ve managed to triple its revenue, so I’d say things have gone pretty well.”

Today, Mark says his favorite part of his job is receiving positive feedback from his clients. “I like hearing from customers that they had a good experience with my guys. I’m the first person they meet, but once the actual work begins, their experience is mainly with my crew and foremen, so I’m always glad to hear they received the level of service and quality I promised at the beginning.”

A resident of Alamo (where he lives with his wife, Hui Ling, and son, Jaedi), Mark spends his time outside of work engaged in a variety of interests, from classic cars to sports. “I’m a classic car enthusiast, and I have a collection of about a dozen English, Italian, and American models,” he says. “I spend way too much time buying, selling and reading about cars. I also like playing pickup basketball and following the Golden State Warriors and San Francisco Giants.” Additionally, Mark enjoys going to the beach, taking bike rides and skiing at Tahoe with his family.

In regard to a professional philosophy, Mark espouses the importance of providing a high level of quality. “I think most people would rather pay $12 for a great cheeseburger than $8 for a lousy one,” he explains. “By the same token, we provide a very high level of service, but we’re certainly not the cheapest company out there. I’ve kept my crews busy for the past decade not by being the cheapest, but by being very good and taking care of our clients. That formula seems to work well, so I’m sticking with it.”

When asked the first thing he’d do if he were to retire tomorrow, Mark says he’d devote more time and energy toward his automotive avocation. “I would probably be more active with my classic car hobby. In general, I’m less interested in showing my cars than in the horse-trading aspect, so I’d probably be buying and selling more high-value cars.”

Ask Me Anything!

Q: What was your first car?
A: A 1971 Ford Mustang Fastback.

Q: What’s your dream car?
A: I’ve owned almost every one of my dream cars. I guess the one that has remained out of reach is the Mercedes-Benz 300SL Gullwing. Those are in the seven-figure range and I’m not sure I’ll ever be a seven-figure guy.

Q: If you could immediately master any musical instrument, what would you choose?
A: The guitar. I play a little already, but I’d like to be better at it.

Q: What’s your favorite snack?
A: Pistachio nuts.

Q: What’s the most death-defying feat you’ve ever attempted?
A: Surfing the Banzai Pipeline in Hawaii.

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A Crucial Component of Earthquake Safety


OAKLAND — Due to concerns about earthquake safety, many Bay Area homeowners are taking preemptive action by having their homes retrofitted via measures like foundation bolting and bracing. While retrofitting is a great idea, there’s one caveat: if your home’s foundation… Read more

Expert Video Tip

Video: A Firm Foundation for Earthquake Safety

Complete Video Transcription:

OAKLAND — Host, Sarah Rutan: If you’re planning to have your home retrofitted for earthquake safety, don’t overlook the importance of a firm foundation. Today we’re in… Read more

Luis Barrera is owner of Advanced Plumbing & Drain Master, a Diamond Certified company. He can be reached at (925) 338-0371 or by email.

Luis Barrera

diamond certified contributor profile and expert article

Luis Barrera: An Advanced Career

By James Florence, Diamond Certified Resource Reporter

ANTIOCH — When asked how he got into the plumbing industry, Luis Barrera credits a family connection. “When I was in my early 20s, I had an uncle who was a plumber, and through him I became acquainted with the trade,” he recounts. “I was intrigued by the technical aspects and it seemed like I could make a decent living, so I decided to pursue it as a career. About 10 years later, I got my license and started my own business, which I’m still running today.”

Today, as owner of Advanced Plumbing & Drain Master, Luis says while running a business isn’t easy, it’s worth the extra effort. “It’s a lot of responsibility, but it also keeps me motivated. I take a lot of pride in having my own business.” When asked his favorite part of his job, Luis replies that it’s the fulfillment derived from helping others. “I like making my customers happy by solving their problems. There’s nothing better than seeing the smile on a customer’s face after I’ve bailed them out of a bad situation.”

Originally from Belize, Luis came to the United States in 2002. Today, as a resident of Antioch, he expresses his appreciation for the professional opportunities his relocation has afforded him. “In Belize, the plumbing industry isn’t as advanced as it is here, and as a result, it doesn’t pay much. I’m thankful to be in a place where there’s a higher standard of professionalism and plumbers are well-compensated for their work.”

Outside of work, Luis spends the bulk of his time with his wife, Flore, and their two children. “On the weekends, we like doing family activities like swimming, going to the movies and going out to dinner,” he says. “I also play in a soccer league, so every Sunday we all go out to the game.”

In regard to his professional career, Luis espouses the importance of customer service. “I think the key to having a successful business is providing good customer service,” he affirms. “After all, it comes down to having happy customers, and the only way you’re going to achieve that is by being on time, courteous and solving their problems, which is what I always try to do.”

Ask Me Anything!

Q: What’s your favorite sports team?
A: The San Francisco 49ers.

Q: What’s the best gift you’ve ever received?
A: My kids.

Q: Are you an early bird or a night owl?
A: A little bit of both.

Q: What’s your favorite restaurant?
A: Red Lobster.

Q: What’s your favorite thing to do on a rainy day?
A: Go outside and play with my kids in the rain.

Read more

How to Unclog Your Kitchen Sink


ANTIOCH — When your kitchen sink gets clogged, your first instinct might be to call a plumber. However, by using a simple technique, you may be able to solve this problem yourself. Simply cover up the clogged drain hole and turn… Read more

Expert Video Tip

Video: Simple Solution for Sink Clogs

Complete Video Transcription:

ANTIOCH — Host, Sarah Rutan: If your kitchen sink is clogged, there’s a simple technique you should try before calling a plumber. Today we’re in Antioch… Read more