The Board of Appeals on Wednesday will hold separate public hearings on applications for special permits to add in-law apartments to two single-family homes. One application seeks permission to build a 22.6-by-24-foot addition to the rear of a home at 286 Porter St. The other application would convert the basement of a home at 16 Warwick Road into an in-law apartment. The board will meet at 7:45 p.m. in the aldermen’s chamber at City Hall.