Honest Buildings, the startup that's collecting billions of square feet of property data in a LinkedIn-like online database for real estate professionals, efficiency experts and would-be tenants, has just raised an undisclosed Series A round from Mohr Davidow Ventures and RockPort Partners. Chalk up a point for information technology and social media, applied to greening the built environment.

The New York City-based startup previously raised an undisclosed seed round from Spring Ventures partners Nick Allen, Sunil Paul entrepreneur and author Lisa Gansky, former Expedia.com CFO Michael Adler and other angel investors, who also participated in the new round.

Honest Buildings has 250,000 commercial and mixed‐use buildings in New York, representing more than 4 billion square feet of property. It also has projects underway in San Francisco and partnerships with the Environmental Defense Fund, and just announced a 37,000-building project in Portland, Ore.

What it does is tap public data sources on properties, and puts the data online for use by  thousands of building owners and management firms, along with architects, engineers, contractors and other building services businesses. That’s a lot of building data: square footage, building ownership and management, projects and renovations performed on the building, and on the green front, its LEED or Energy Star status. While much of the data comes from a variety of public sources, it also draws on relationships with property owners and management firms to collect proprietary information as well, Josh Boltuch, chief marketing officer, said.

While much of the site’s content is free, the main money-making proposition is to sell premium subscription services to businesses that serve property owners. In that sense, it’s a massive, open-book referral and data service for a host of building-related business relationships, not all necessarily aimed at greening buildings as a main goal.

But co-founder and CEO Riggs Kubiak has said that his property management experience, including his multi-year stint as sustainability officer for property management giant Tishman Speyer, led him to create the site as a way to push the industry to put its money where its mouth is on the green front.

So how does creating such a database drive more green building investment? Boltuch mentioned a few avenues, such as providing green businesses a single source of properties to peruse for likely retrofits or services.

As more sources of data on a building’s green credentials become available, that could expand the usefulness of the site for driving efficiency. New York City’s Local Law 84 requires all buildings over 50,000 square feet to report annual energy benchmarks, and Honest Buildings is working with the city on integrating that data as it comes out, Boltuch said.

It will be interesting to see how a platform like Honest Buildings might compare to the more energy-specific services being developed by the likes of Retroficiency and FirstFuel, startups that use utility and building data to compile energy profiles of buildings. Getting true building energy data into the mix will be the critical next step for the platform's green credentials.

Certainly, getting the basic information up is an important start -- particularly when it reveals where building owners aren’t walking their green talk. Honest Building’s San Francisco project, for example, has shown that a good number of the city’s buildings that are required to provide basic energy data to the city haven’t yet complied with the ordinance. It’s all good and well to provide the carrots to encourage building owners to go green -- but the stick of shaming them into greater efforts can also work wonders.