Another redevelopment of commercial real estate in East Watertown is adding to the pipeline of future life science inventory in the inner suburbs.

Developer Westbrook Partners is planning a 213,500-square-foot office-lab building on a 5-acre site at 85 Walnut St., currently occupied by a 89,000-square-foot office building.

The current occupant of the property, Doble Engineering, acquired 123 Felton St. in Marlborough for a new headquarters last year, and sold the Watertown property to Westbrook Partners for $17.5 million.

The project designed by Spagnolo Gisness would include a 451-space parking garage and 97 surface spaces.

The project is part of a series of acquisitions by commercial developers in Watertown seeking to redevelop industrial and commercial buildings into lab space as the life science industry grows in new markets surrounding Cambridge.

Alexandria Real Estate Equities and National Development this month acquired the Mount Auburn Club fitness and tennis facility on Coolidge Avenue for $32.6 million, with the intent of building an office-lab complex.

While lab space inventory remains chronically scarce in East Cambridge, developers also continue to buy older commercial properties in the Alewife section for future projects. IQHQ Inc., a life science REIT, this week announced it’s agreed to buy the 26-acre headquarters of construction material supplier GCP Applied Technologies near the Alewife MBTA station for a future life science campus.

Lab space has accounted for nearly three-quarters of all absorption in Boston suburbs in 2020, according to research by Colliers International. Greater Boston is the favorite market for the 10 largest life science landlords, which have over 36 percent of their portfolios concentrated in the region, according to a report this month by Newmark Knight Frank.