The museum that operates the Glass House, the internationally known modernist landmark designed by architect Philip Johnson, is moving to expand arts programming and the fundraisers its hosts on the building grounds in New Canaan.

First, it had to win over the town’s planning and zoning board, and some neighbors who had other ideas for what should be allowed in the suburban, mainly residential area.

After scaling back its request for modifications in discussions with nearby residents, the Glass House won approval this month for changes to the permit. An annual fundraiser, once capped at 250 people, can now have as many as 400 guests, hours for evening tours have been extended, and the site can host four events a year with as many as 150 people.

“We think a fair balance has been struck between our programming and the property owners’ rights,” said Greg Sages, executive director of the Glass House.

Johnson, who died in 2005, built the house on a hilltop for himself in 1949. A steel structure with only glass walls, the house has been widely influential and famous for its re-imagining of domesticity. The house is a National Trust Historic Site and has been operated as a museum for the past decade.

The Glass House has been looking to expand its tours and arts programming to bring more people to the 49-acre property, which also features 13 other structures including a permanent collection of 20th-century painting and sculpture. Its programs this season include dances, art exhibits and tours that combine stops at the Glass House with tours of other modernist homes in New Canaan. One day this week, photography students from New Canaan High School visited the grounds.

Some neighbors expressed concern at a meeting in January that the changes would bring more traffic and noise.

“The immediate neighbors had some concerns,” said Steve Kleppin, the town planner. “Outside of that group, there was support for the Glass House from people within town.”