Here’s what you need to know about Boston-area development this week

Critical Mass. is a weekly roundup of the most notable development news in the Boston area. This week’s includes a possible independent dorm in Davis Square, a construction-related warning from Logan Airport, and an apartment tower in the Theater District.

Rendering via Fortis Property Group

Brooklyn-based Fortis Property Group received $87.5 million in construction financing to construct a luxury apartment building on what’s currently a surface parking lot at 47-55 Lagrange Street in Boston’s Theater District—yet another change to parking norms downtown. The tower is expected to run to 21 floors and to contain 148 market-rate apartments and 22 affordable ones. Construction is imminent.

Meanwhile, over in Somerville’s Davis Square, Scape—the London-based firm trying to build the nation’s first independent, unaffiliated dormitory in Fenway—acquired the ground lease on a run of retail property and an adjoining parking lot. It looks like the company is planning to try to build a dorm here too.

Also in Somerville, construction started on a nine-story, 289,000-square-foot project off South Street in the city’s Boynton Yards project. Developers DLJ Real Estate Capital Partners and Leggat McCall describe 101 South Street as “the largest state-of-the-art lab development in Somerville’s growing life science market.” It’s also yet another example of a life sciences project in the Boston region.

As are the big plans in Boston’s Fort Point at what was once supposed to be General Electric’s new headquarters. Recall that Alexandria Real Estate Equities and another firm bought the site in May. Alexandria already had a reputation for life sciences developments, and it looks like that’s what it has in mind in Fort Point: an up to 650,000-square-foot campus at 5, 10, and 15 Necco Street.

Rendering via City Realty Group

In Jamaica Plain, developer City Realty Group officially started construction on a 39-unit condo building at 3193 Washington Street in Egleston Square. Its units start in the $400,000s and that’s no accident: The developer is targeting the spreads toward buyers who might not otherwise be able to afford Boston’s increasingly stratospheric prices, particularly for condos.

And, in Dorchester, the Boston Zoning Board of Appeal signed off on developer JPA Development Company’s plans to convert the Our Saviour’s Lutheran Church at 500 Talbot Avenue into a four-story, 40-unit apartment building. It will include about 2,000 square feet for a space for the church.

Finally, major construction—and plans for more—are driving transportation changes at a rapidly expanding Logan Airport.