The owner Dereck , he has many years experience and did the good job . His quote is reasonable and completed the inspection and installation on time. Highly recommended. read more

Derek recently replaced the roofs at both our properties, he was very easy to work with, professional, and provided a quality end product at a very competitive price. I'm very happy to recommend him! read more

This review should have been written 12 years ago. In 2008, Derek put a new (composite) roof on my house. I chose Derek bc his pricing was hard to beat and reasonable. This week, I did a routine check of the roof and discovered that it is in good shape, which reminded me of Derek and his crew. I checked online today and found that Derek is still in the business, which was no surprise to me. read more

Dereck is great, so knowledgable and so thorough. He and his crew did an excellent job to repair my roof. Definitely recommend his company to everyone that needs a roof work. read more

We are so lucky to have Dereck as our roofer. It is a truly peace of mind service. You know how difficult it is to have this feeling during remodeling. Dereck is very reliable, knowledgeable, professional and responsive. 1000% recommended if you are looking for a roofer in bay are! read more

Dereck gave us a fair price and the roof looks great! He went out of his way to make sure we understood what they were doing, and communicated with our other contractors as needed. They even painted our roof pipes, new and old, to match the rest of the roof. I'll highly recommend this company in the future, and will use them again if I'm still kicking in 30 years! read more

We were so right to ask Dereck to do the roof project. It was great and smooth. I really enjoyed working with Dereck because he is so nice and reliable. He is also pretty happy to help if you have some other questions or asks. I shopped around and he gave the best quote, eventually did an awesome work!!! I would 100% recommend him and his company -- principle roofing. read more

5 star. Dereck is really amazing. The whole process is very reliable and smooth. Dereck is very transparent and super responsive on the roof replacement process. He kept me updated on all the job status. (when to start, how long it will take, when will inspector comes) Whenever I have questions, he will reply immediately via text. I strongly recommend Dereck for roof installation. The price is also very good compared to other companies I asked. read more

Had our home roof replaced by Dereck. Dereck is awesome! Can't go wrong with Dereck in terms of pricing, professionalism, attention to details and execution. From quoting, explaining options, scheduling, being on site every day during install and completion per original schedule, Dereck was great! Highly recommend Dereck for any roof work! read more

We just completed our new roof with Derek's company, I am very happy with quality of workmanship Derek & his team put on. Derek is quite different from owner of other roofing company, from very beginning of estimate, throughout entire replacing process, I can find him on our roof line every single day. He's very detail oriented, always listening to customer request/concern, and point out his crew to each junction whenever special attention/treatment is needed. I am a hands-on type engineer, I got to say I learned so much from him sharing roof job know-how, you can easily see he's really passionate about what he does everyday, I am glad I follow thru with him about entire replacing process, now I really appreciate good roofline workmanship :-) read more

We wanted to replace our old tile roof with composite shingles. Dereck was referred by my friend and we had three quotes and Dereck's price is similar to another one but we chose Dereck because he was super fast in replying my messages. Before installation, Dereck brought 5 shingle samples to my house and walked me around the neighborhood and showed me different color choices. Dereck was very knowledgable about roofing and patiently answered every question I may have. The whole installation took 4 days including rain gutter replacement. After the installation, my neighbor texted me and complimented my new roof. Dereck also helped to fix two small holes on my wall for FREE. Overall, a great job at a reasonable price. read more

I asked 6 roofers to give me estimation. 3 of them do not do metal roof. Among the rest three, Derek Loi gave me the lowest price. But I chose to trust him because after talked to him quite a few times, I feel he is a real roofing professional. He knows how to do it. He has various insurances; He has long term roof workers. He answered my questions patiently. It turned out my metal roof is very good.I am satisfied. If you need to find someone to do your roof, Dereck is the right guy. read more

Mr. Dereck Loi of Principle Roofing did our new roof and gutters. He always kept us updating every step of the way, so we coluld be sure that he installed our new roof and gutters in the right way and finished the project on time. He provided us with excellent customer servicetomer service, and I would like to recommend Principle Roofing for any roofing work and gutters instalation, based on the qulity of the work and he reliabliity of Mr. Dereck Loi. read more

We had a leak and called Dereck. He promised to come in the afternoon. He came at the end of the day and the only thing that he did - gave advice to fix it ourselves. Was not interested in any projects from fixing a leak or redoing the roof completely. read more

We had looked for a roofer for several weeks, and got at least 5 other bids. Principle Roofing was very good and had the best quote. We live in Saratoga, and wanted a higher end roof. They did a great job! We had the Presidential TL roof in Autumn Blend color. It looks great! The workers were nice and efficient. They kept things clean, and the work was done in a very professional manner. I highly recommend them. read more

I had Principle Roofing do a 2000 square foot roof in Sunnyvale a few years ago. I was happy with the work that he did then and I'm still happy with it. Principle was the lowest of four bidders. He was clear about what he was going to do, worked his schedule around our needs, did not complain about squirrelly little flashing problems, always kept the place neat, performed the work in an organized fashion, didn't cut any corners, had friendly workers, was always available to discuss options and progress. He did a good job. If I had another roof, I'd hire him again. read more

Principle Roofing replaced our existing roof and they did an excellent job. I'm really happy with the whole process and I think our new roof turned out great. We started with a detailed estimate and the price we were quoted was extremely reasonable. The crew was friendly and polite, and kept a clean work site. The job was done right on time and now we have a very nice roof. If you need a new roof, be sure to get a bid from Principle Roofing. I think you'll be pleased. read more

Had a roof put on by Principle Roofing in 2013. We have a pretty standard ranch burger single story home so not very challenging. Dereck Loi, the owner came out to bid on the project. We went with him given our budget as well as his experience with the Decra metal roofing system. Fast forward to the 2014 rain deluge and to our surprise, our new roof sprung a leak! Our 20+ year old cedar shake roof hasn't leaked ever. We were bummed. This is when you get to really see what a company's true worth is. A call to Dereck and the next day, he was up on the roof assessing the leak. He's got it fixed now so with the coming rain storms, we feel very confident the newly repaired roof will last for many leak free years to come. read more

Noticed a leak around a lighting unit in my kitchen, and since I'd had Principle re-roof the place 3 years ago I gave them a call. It was a Sunday morning so I didn't expect to do more than leave a message to set up an appointment later. Instead I talked right to Mr. Loi who got to my house before lunchtime and, in the pouring rain, went up on the roof to find a cracked vent that was causing the trouble. He sealed it up and told me to contact him if there were any future problems, and that the roof was guaranteed for 5 years so no charge. I can't tell you what a weight was lifted off my shoulders. If you need a roofer I really can't recommend Principle more highly. read more

After a walk through with the contractor on the roof, I called them week after week after week for getting a quote. They told me it would take couple days each time. Finally, I go for another contractor after a month of calling for quote. It is slow market time in 2009 and I got this treatment. Imagine how they will be when they are busy. read more

Derek worked very professionally when he and his team conducted the re-roofing works for my old house in west San Jose late March. I will strongly recommend Principle Roofing to my local friends due to Derek's excellence. read more

It seems everytime we move to a new house, we end up replacing the roof. I've done it 4 times so far, and this experience with Principle Roofing was the best. Derek ran the project for us. He is extremely knowledgeable and a truly good and honest person. I would recommend him to my own family. He went out of his way to help us. I've never written a review about anyone or any service, and the fact that Derek was so good prompted me to actually sign up to Yelp and give him a good review. I hope other roofers and home repair companies see this and learn what good service can get them. read more

Principle Roofing just finished a re-roof of our house and detached garage. They were able to work around our schedule which was very important. They did a great job! My neighbors have been stopping by to ask who did our new roof and asking for the phone number. I highly recommend Principle Roofing! read more

I recently put my house on the market, and, at the inspection, they found some problems with the shingles, even though the roof was only six years old. I had to correct the problem right away, and so I called Dereck Loi from Principle Roofing. Even though he was busy, he managed to find time for me on short notice. He came to do the work promptly and did an excellent job at a very reasonable price. He always answered the phone right away and was never annoyed by my many phone calls. Dereck Loi is an excellent roofer and very professional, and I recommend him highly! read more

The only company that sent a email refusing to bid. My roof is not configured to his capabilities.Most roofing companies do not contact at all and leave you with no bids. Principle Roofing is very considerate to the homeowner. read more

I had 4 roofers to come to estimate the work of reroofing my home, Dereck Loi from Principle Roofing gave me a very good quote. It was not the cheapest quote, but I still chose him based on his knowledge and attitude. Dereck truly knows the roofing stuff, he paid good attention to every specific detail issue of my house. Both my wife and I feel he is a trustworthy professional. Our feeling is absolutely right. My home reroofing project was completed today, Both my wife and I really like the quality and process of Dereck's work. I decide to write this review to share my joy and recommend strongly for Dereck's business. Please note that my wife is very detail oriented. We had many remodeling projects for this house and the other house, every main part of the current home was changed once or even twice. So far only this project pleases us in both quality and price. If you want to choose a roofer to replace your old roof, this is the right choice. read more

Just finished my roof. They have done a great job to accommodate our request. I got 5 quotes from different companies which all have good reviews on yelp. Principle Roofing was referred to me by my realtor. Principle came with the best bid. Dereck definitely knows his stuff, since he s the owner, the sale and the supervisor. Not like other companies which sent out their sales-persons who did not know what they talked about and/or had never done a roofing project and some quoted me for items that were not suitable for my roof. Anyway, go back to Principle, Dereck followed up closely in every step of the process and communicated with me in advance. The job was finished within 3.5 days and they did the clean up. However, Dereck did make a couple of price adjustments after the first quote, but before we signed the contract. He said he miss-quoted the radiant barrier osb price and he underestimated the length of our gutters. But these are just minor and we are more comfortable with him than the other companies. In short, 5* and highly recommend. read more