For architects, complying with building codes means navigating labyrinthine layers of regulations that vary between municipalities. Sorting through different codes and keeping track of updates is a daunting task and, in a worst-case scenario, a mistake can cost thousands or even millions of dollars to tear out and fix. Firms that can afford it hire building code consultants, but a startup called UpCodes wants to make code compliance easier for all builders.

Founded last year by brothers Garrett and Scott Reynolds, UpCodes is currently taking part in Y Combinator. It now has more than 45,000 monthly active users and claims 11 percent growth week-over-week this year. Its app puts building regulations into one place, makes them searchable and adds collaboration tools so team members can research and share notes on projects.

Before founding UpCodes, Scott worked as an architect in New York City and Hong Kong.

“I came out of school where design is freeform and architecture is a very creative endeavor, then got into the workforce and realized how difficult the regulation atmosphere is to navigate,” says Scott. “I realized how difficult it was for me, my colleagues and individuals to understand those codes. It drove me to a point where architecture wasn’t enjoyable any longer.”

Looking for his next step, Scott talked to Garrett, a software engineer at construction software startup PlanGrid, and they decided to tackle building codes, hacking together an app over Thanksgiving break. As they got deeper into the project, however, the brothers discovered that the problem was even more complicated than they had realized.

Being code compliant means builders need to deal with multiple layers of building regulations and figuring out which ones are relevant to their project. There are codes at the federal, state and local jurisdiction (like city or county) level, as well as more specific codes that deal with areas like plumbing, electrical wiring, fire safety and accessibility for people with disabilities. Builders need to pay attention to the smallest of details, like the height of stair risers or handrails, to avoid expensive construction tear-outs and redos.

Many builders research code by going through physical books or PDFs. UpCodes simplifies the process by putting all building codes in one place and also updating them in real-time. Codes are overhauled once every few years, but in between there are a lot of smaller changes. The startup immediately updates all regulations in its app with tools that monitors changes on the websites where they are posted. One benefit of using UpCodes is that it can make it easier and less costly for architects to work in different jurisdictions.

The brothers say that in 2017 so far, UpCodes has processed more than 110,000 searches, making up what they say is “the world’s largest trove of construction search data.” In the future, this will be used to build intelligent prediction models for building codes.

Garrett, who researched machine learning and artificial intelligence at UCLA and was on PlanGrid’s machine learning team, says that in five to 10 years, architects may be able to draw up blueprints and see immediately if they are code compliant. In the meantime, however, UpCodes will focus on adding more building codes to its database. The app currently has building codes for about 40 states, as well as New York City. The Reynolds say they plan to add Seattle, Los Angeles and Denver next due to user demand.

UpCodes’ collaboration tools allow users to hyperlink to sections of code and create project folders to share with team members. Being able to save project notes helps firms build institutionalized knowledge, Scott says.

“Firms will often do projects that repeat themselves and have similar requirements, but in my experience, a lot of that code research gets done twice,” he explains. “We try to remove as much of that as possible and bring it to future projects as well.”