BuildZoom was founded by Jiyan Wei, left, and David Petersen, who grew up as friends in Bethesda, Md. They're pictured in BuildZoom's San Francisco headquarters.

BuildZoom, a San Francisco-based tech startup, has tapped into public records to put online what it says is "the complete remodeling history of Chattanooga."

"Chattanooga residents can now access information on every single remodeling and construction project that has [begun] over the past 10 years through BuildZoom's Permit Mapping project," the company said in an announcement of the new service.

Users key in an address and can see the details of what's happening to homes in their neighborhood, Buildzoom says. Additional features allow users to filter by project type, for example, solar-electric power, and project cost.

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BuildZoom’s building permit map of Chattanooga can be at

Chattanooga's not alone. BuildZoom has collected and put into map form information from more than 600 building permit departments in roughly 500 cities and 100 counties. The company, which was co-founded in 2011 by David Petersen and Jiyan Wei, describes itself as "the world's largest collection of construction data, which includes information on over 3.5 million licensed contractors and 80 million construction projects nationwide."

"We have rolled it out in about 300 cities, so far," Wei told the Times Free Press.

He said the building permit map is meant as a service of BuildZoom, which makes its money by helping people find contractors for projects such as home remodeling. If someone hires a contractor they found through the website, BuildZoom gets a percentage.

So far, 172 of the 2,762 licensed contractors based in Chattanooga have signed-up for BuildZoom, Wei said. However, information about all 2,762 contractors is available on, he said.

Chattanooga-based Better Homes, owned by contractor George Allen, gets a BuildZoom score of 97, which puts it above 80 percent of the 55,771 contractors in Tennessee, the website says. BuildZoom generally recommends hiring a contractor with a score of 95, or higher, which means Better Homes makes the cut.

That was news to Allen.

"I've never heard of the site, to tell you the truth," said Allen, a lifelong contractor who specializes in total bathroom and kitchen remodels who's worked about 15 years in the Chattanooga area. "It's something that I'm getting for free that I never signed up for."

This isn't the first time Allen has been contacted by someone who's found him on a website that connects homeowners with contractors.

Allen said people have asked him about doing work after finding him on, a website that encourages people to submit a photo, video or short description of the work they need completed, and then "sit back" and "let top-rated contractors bid to complete your project." Allen didn't wind up getting any work through gosmith, but he said, "That's just how it goes."

In 2011, Wei and Petersen built the initial version of BuildZoom to solve personal challenges they both experienced with finding reliable home improvement contractors. They made their offering available to the public and, before long, saw demand for their service increase dramatically.

In 2013, they moved to San Francisco and participated in Y Combinator Winter 2013 class., a Mountain View, Calif., startup business "accelerator" that has funded 800 startups since 2005, including reddit and Dropbox. Soon after, the two boyhood friends raised an additional round of seed funding led by Formation 8's Joe Lonsdale, the co-founder of Palantir, a mission-driven computer software and services company, specializing in data analysis, BuildZoom's website says. The company now has about 50 employees, Wei said.

Currently, BuildZoom says 1 million visitors come to each month for information on contractors and remodeling projects.

Contact staff writer Tim Omarzu at or or business or 423-757-6651.