Even though Pearson had a permit for the previous house, town bylaws require him to get another one before rebuilding.

"We're trying to fit in within the context of the community," said Miguel Linera, the architect who filed for the special permit. "I'm a Hopkinton resident so I know what that context is. We have preliminary drawings, but we're not ready to show them yet."

Iris Carey, 4, and Violet Carey, 5 1/2, died in the July 24 explosion.

The girls' parents, Heath and Tara Carey, filed suit in Middlesex Superior Court, alleging that a leaking gas line caused their home to explode. They're suing Pearson, NStar and Inner-Tite Corp. of Holden, which made the gas-line fitting. The case is ongoing.

Pearson, who lives in Hopkinton, could not be reached for comment.

Linera would not comment on the explosion, saying he is not the "developer, owner or paying for the new building," but he did say he hoped to include some commemorative feature in the design.

"It would be my wish as the architect to add some architectural element that would not simply forget the event," he said.

"One of the moves that I was trying to introduce uses one of the stair towers to illuminate that element, creating some sort of beacon or memorial -- sort of an anchor element that would face the street and perhaps move people in some way."

He said he does not want to simply post a plaque in memory, but actually incorporate a commemorative element into the building's design.