All four were taken to the hospital after the accident at about 10 a.m Thursday at the house at 138 South Gate Lane in the Southport neighborhood.
The workers reportedly fell about 15 feet into the basement of the home. Three of them had to be extricated from the debris, officials said.
Two were transported to Bridgeport Hospital for treatment, and two were taken to St. Vincent's Hospital in Bridgeport. The injuries were not life threatening, officials said.
The federal Occupational Safety and Health Administration was called, and officials were en route to the scene.
The house at 138 South Gate Lane was bought by Southgate LLC for $650,000 in May. It was first built in 1939. It is located off Pequot Avenue near the Westport border. The house is undergoing major renovations.
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