100 Chestnut St. in Somerville/Image courtesy of Gensler

As more life science conversions and new developments were completed without tenants, Greater Boston’s lab vacancy rate rose to 13.7 percent in the first quarter.

The figure, up from 10.8 percent at the end of 2023, represents nearly 7.6 million square feet of direct lab vacancies throughout the region’s nearly 56 million-square-foot inventory of life science properties.

The vacancy rate has increased for eight consecutive quarters, CBRE researchers noted in the Boston metro lab report. A wave of new lab projects’ completions have coincided with a decline in private investment in the biopharma industry.

“As economic uncertainty lingers, many companies, both public and private, remain cautious in their approach to real estate decisions,” the report states.

Just two new leases over 50,000 square feet were signed in early 2024, both at speculative lab projects: ADA Forsyth Institute’s 76,000-square-foot lease at the new 100 Chestnut St. development in Somerville’s Brickbottom, and BPG Bio’s 70,000-square-foot lease at 300 Third Ave. in Waltham. 

The lab market recorded 183,000 square feet of negative absorption during the quarter, but some local submarkets including East Cambridge are remaining insulated from the worst effects of the downtown.

The 16.8 million-square-foot Kendall Square submarket ended the quarter with an 7.6 percent vacancy rate. By contrast, more than half of the lab space now is available in its crosstown counterpart: the 2.9 million-square-foot West Cambridge market has a 54 percent vacancy rate and 19.1 percent vacancy rate.

Boston’s largest lab cluster, the 5.2 million-square-foot Seaport market, now has a 19.1 percent vacancy rate, and no leases were signed in the first three months of the year.

The 20.1 million-square-foot suburban market recorded positive absorption of nearly 235,000 square feet, largely because of the 100 Chestnut and 300 Third Ave. deals, but now has an 18.1 percent vacancy rate.

CBRE currently is tracking 9.7 million square feet of lab projects still under construction in Greater Boston.

But tenant demand remains skewed toward smaller requirements under 25,000 square feet, which comprise 26 percent of the market’s demand by square-footage.