The Jaffrey Planning Board approved amendments to a plan for 58 new units on the former St. Patrick’s School grounds.

The plan calls for a mix of housing, including townhomes, duplexes and a 30-unit workforce housing apartment building.

Construction on the townhouses is proposed to begin this summer.

The plan, previously approved by the Planning Board in 2024, came back before the board on Tuesday for several amendments, primarily to the proposed size of the 14 duplexes.

The change would increase the size of the approved duplexes from 1,590 square feet to 2,334 square feet.

Jonathan Devine of TF Moran, representing owners MJ & MJ Realty, said the reason for the changes was a “scaling discrepancy” between the civil engineering plans and the architectural plans that was not caught before the plans were submitted.

Planning Board member Keith Dupuis noted there was a “large discrepancy in the numbers.”

Jack Belletete, one of the owners of MJ & MJ Realty, said the discrepancy should have been caught. He explained that building the units with the approved dimensions would make them too small.

The change in building size prompted several other amendments to the plan. The units would largely remain in the same proposed area, but be closer together, reducing the separation between them by about five feet. One duplex would be moved entirely from its previously planned location, where it was partially encroaching on the wetland overlay district buffer, to an area completely outside the buffer.

The stormwater management system on the site was adjusted to accommodate additional roof and impermeable surface space.

Audience members offered no feedback on the changes. Tom Ahlborn-Hsu, the chair of the Conservation Commission, said the plan lessened the impact on the wetland conservation overlay district and raised no objection.

The Planning Board discussed the proposed changes briefly and raised no objections.

The board reapproved previous waivers and a conditional use permit for the updated plans and then approved the amended plan itself, finding the amendments were “minor changes” to the site plan approved in 2024. The vote was unanimous.