Proponents of the $42 million renovation and expansion of the Martha's Vineyard Hospital will go before the Oak Bluffs zoning board of appeals next week for a special permit.

The permit would clear the way for the new building to be larger and taller than normally allowed under the town zoning bylaws.

The public hearing, scheduled for Thursday at 6 p.m. at the town senior center, will be dedicated entirely to the hospital application.

At present, the combined size of the existing hospital buildings in the hospital care district in the Eastville section of town is about 140,000 square feet - well beyond the 100,000-square-foot maximum allowed under town zoning.

If approved, the special permit will allow the hospital facility to expand to about 221,000 square feet, and also will allow for a two-story addition with steeply-pitched roofs higher than 35 feet.

In December, the Martha's Vineyard Commission unanimously approved the hospital renovation despite misgivings on the part of some commissioners with the existing location. They spoke of their concerns about the present hospital site, which they described as too small, at risk for natural hazards and situated within a historic residential neighborhood in the Eastville section of Oak Bluffs.

But in the end commission members agreed those factors were eclipsed by the pressing need for an improved emergency medical facility on the Island.

In response to residents' concerns about the impact of the project on their homes and neighborhoods, the Oak Bluffs board of selectmen in January agreed to appoint a special committee to serve as a bridge between homeowners and the hospital construction team over the next few years.

The six-member committee will be a largely informal panel. Town officials expect its meetings to serve as a forum for residents to ask questions, air concerns and generally keep tabs on the project.

Town administrator Michael Dutton said this week that the committee likely will hold its first meeting next week. Because the neighborhood committee is informal, he said meeting notices will not need to be posted in town hall and local newspapers.

Hospital officials expect to break ground on the project once the special permit from the Oak Bluffs zoning board is secured.