Shoddy work by the contractor over a decade ago most likely led to extensive water and termite damage in several classrooms in the West Tisbury School’s newer wing, according to a recent engineering report prepared for the school.

Town and school officials are now negotiating with J.K. Scanlon of Falmouth, the contractor who built the school wing and is also currently the general contractor for the town hall renovation project. Town officials are hoping that the contractor will either pay for the school repairs or reimburse the town, and that damage will be repaired in time for the start of the school year on Sept. 10.

The damage is confined to the school’s newer wing that was built over a period of two years and completed in 1996. Town insurance will not cover the repairs.

The school district hired engineer Geoffrey Koper to conduct a site visit to the school on May 18 and compile a report outlining the water and termite damage and recommend a plan for repairs.

Mr. Koper started by inspecting a wall and window frame in a single classroom and found extensive damage caused by rot and a termite infestation, which allowed water to penetrate the framing.

The termite and rot damage was both structural and cosmetic, the report said, and the water infiltration caused mold to grow on the cavity side of the interior wall. Mr. Koper concluded that poor craftsmanship was a factor in the damage.

“The principal cause of the water infiltration appears to be the poor quality of the joint between the window sill and the side casing . . . the window installation in general was poorly done and normal construction weather-proofing practices such as the installation of the proper flashings and window splines were not included in the original work,” the engineer said.

Mr. Koper said another factor leading to water infiltration was the lack of a galvanized metal sleeve connecting the HVAC unit to the exterior grille, which allowed wind-blown rain to enter the wall while also blocking condensation that formed in the unit from draining properly. Damp conditions may also have encouraged termite access to the wall cavity, he said in his report.

Mr. Koper said he inspected the construction drawings for the building and concluded the windows were not installed as detailed. When he inspected other windows in other classrooms in the same wing of the school, there were “strong indications of water damage at all of the sill casings,” he said.

Mr. Koper recommends in his report that all of the exterior wood trim surrounding each HVAC window be removed to determine the full extent of the water and termite damage. This will allow general contractors interested in bidding on the repairs to get a more accurate estimate for the work.

The report recommends that all damaged wall sheathing and framing be removed and replaced, and new building wrap be placed over the sheathing to protect seams. The window units should then be removed and reinstalled, the report recommends, and water-damaged and moldy gypsum board should be removed.

The windows will also need to be inspected by a pest control expert, who may recommend treatments to the wood in order to remove any remaining infestations and prevent future problems. New window trim should then be installed, as well as new exterior shingles, the report recommends.

West Tisbury school vice principal Robert Lane said yesterday that the exterior wood has already been removed, revealing more damage in other rooms in the new wing. He was reluctant to go into further detail pending the outcome of the meeting with J.K. Scanlon this week.

“I can say we are doing what we need to do to make sure the building is ready to go for the start of the school year,” Mr. Lane said.

Vineyard schools superintendent Dr. James H. Weiss said yesterday it is now evident the damage in the newer wing is extensive. “The most recent reports are that the damage is widespread, but not as widespread as we initially thought, which is a bit of good news,” he said.