MICHAEL PRIFTI, 60, of Wynnewood; Eric Rahe, 56, of Phoenixville; and Michael Ytterberg, 60, of East Falls, are principals in BLT Architects. The second-generation Center City firm works in mixed-use, multifamily, education and hospitality spaces. I spoke with Prifti, who's managing principal.

Q: What sets BLT Architects apart from other firms?

A: We don't bring preconceived notions to any opportunity. Our higher-education work has informed our hotel work. Similarly, the hotel work is showing up in residential where there's lots of interplay in the amenity space. We're accustomed to cross-pollination. I think most other firms specialize more in niches.

Q: Current projects?

A: We're in a surge of residential design and construction. We have two apartment towers under construction at 3601 Market and 3737 Chestnut . We have other towers in Center City in design and should be in construction soon.

Q: Your clients?

A: We work with building owners, which could be a developer like Dranoff Properties. We work with universities, including Drexel, Penn, Villanova. On the institutional side, we've worked for Philadelphia Parking Authority and hotel chains Marriott and Loews.

Q: Notable projects?

A: We collaborated with Cesar Pelli on Cira Centre, which has led to work on Cira Centre South. We also worked on the Water Club at Borgata in Atlantic City, the Lincoln Ballroom at the Union League and Hamilton Garden at Kimmel Center.

Q: What part of the biz contributes most of the revenue?

A: Residential makes up about 75 percent. In the past, 75 percent had been driven by resort marketplace.

Q: The biz model?

A: Most work is a fixed fee negotiated with clients. Generally, the fee on a residential tower would be 2 percent of the construction cost. So our fee on a $100 million tower would be $2 to $2.5 million. On a smaller project, the percent fee is higher.

Q: Biggest challenge?

A: I've been managing principal since 1994, and we were the same size as now, 65 employees. We grew to 85 in a few years. We were working in Atlantic City and had an opportunity to work in Las Vegas. By 2008 we had 140 employees with offices here, Las Vegas and Atlantic City.

Q: So the firm is less than half the size it was in 2008?

A: When the economy was hot in 2006-07 we worked on multibillion-dollar resorts. The recession hit us hard. We downsized and regrew the firm so it wasn't dependent on resorts.

Q: How big a biz is this?

A: We're north of $12 million a year revenue. Since January we've added 15 employees.

Online: ph.ly/YourBusiness