New homes less than 3,500 square feet could soon have to adhere to stricter energy efficiency standards in Southampton Town.

Currently town code requires a Home Energy Rating System index of 80 on a 100-point scale with 0 being the most efficient. Under a proposed measure that was the subject of a public hearing Tuesday, the maximum rating could be lowered to 70 for houses 3,500 square feet or less.

An initial hearing on July 26 was adjourned so the town board could acquire more information about how much this would cost homeowners.

The board discussed this change at its work session Friday with Michael Benincasa, the town’s chief building inspector, David Machke, a HERS rater, and John Burrows, a former builder and an energy consultant. They presented the board with numbers crunched by a program specifically designed to calculate energy savings at different HERS indexes and the cost to get there.

A principal matter of discussion both Friday and at Tuesday's hearing was on how the legislation would affect a homeowner’s ability to take advantage of rebates offered by LIPA; if a certain level of energy efficiency is mandated, many times it can disqualify a homeowner for a rebate.

According to Machke and Burrows, it is impossible to address that now because LIPA is still in the process of codifying its rebates.

Along with changing the HERS rating, the proposed law would also switch the measurement of energy efficiency. Currently the town, and LIPA, use an Energy Star rating, where a high score is good. The proposed switch to the HERS index, where a low index number is better, added to the confusion about an already complex issue.

The ratings required for larger buildings — an Energy Star rating of 87 for dwellings between 3,501 and 4,500 square feet and a rating of 90 for dwellings bigger than 4,501 square feet—would stay the same, but be converted to the HERS index.

The measure was tabled so the board could gather more information and await LIPA’s decisions.

Supermajority for PDDs

A public hearing Tuesday on an amendment to the law that would require a supermajority vote of the town board to approve a planned development district was filled with praise for the change.

A planned development district is a zoning tool that permits greater density on a parcel than current zoning allows in exchange for a public benefit.

The town’s planning board supports the supermajority rule as does the Group for the East End, which was represented by its executive director, Bob DeLuca, and the East Quogue Citizens Advisory Committee, represented by Joan Hughes.

To change the law, since it would restrict the power of council members, the town has to go to public referendum. To make get the referendum on November election ballot, the board will have vote to approve it at its August 23 meeting.