A sleek, 4,300-square-foot building under construction by a foundation created by renowned British architect Sir Norman Foster is causing a stir among neighbors on the Tisbury Great Pond.

The building was unanimously approved by the West Tisbury planning board three years ago as a three-bedroom single-family home for guests of the Fosters, who live across the pond at Blue Heron Farm. The area where the property is located is zoned for residential use.

But the website for the Norman Foster Foundation touts the building as a retreat center to advance its mission of helping new generations of architects, designers and urbanists to anticipate the future.

“Designed as a flexible space to accommodate a range of multi-disciplinary activities including think tank sessions, workshops and seminars, the retreat will also host a residency programme for selected fellows of the Norman Foster Foundation,” according to the website, which features drawings and photographs of the building under construction.

An internationally acclaimed architect, Mr. Foster is noted for steel and glass structures that incorporate natural light and green spaces to infuse futuristic design with an appreciation for the environment. His best-known buildings include London city hall, the Hearst building in New York city, the Reichstag in Berlin and Apple headquarters in Cupertino, Calif.

At a meeting of the West Tisbury planning board Monday, members heard a litany of concerns from neighbors, ranging from lack of parking at the site to runoff from construction activities to the effect on the water table from the large number of evergreen trees that have been brought in to border the site.

“My concern is . . . well, I have many concerns,” said neighbor Marilyn Hollinshead. “Its application was for a residence. It is not a residence. It is going to be a conference center,” she said.

Aerial photos of the site displayed at the meeting appear to show a completed building framed by a heavy border of trees. The surrounding pondfront area is predominantly open grassland, its sandy soils dotted with scrub oaks and cedars.

Sarah Doyle, who manages the Pond View Farm equestrian center, said excavation on the property had turned two of her horse paddocks into wetlands that could no longer be used.

“I’m most concerned that we have the most massive change I’ve ever seen in any piece of landscape in West Tisbury or on-Island that I have seen — massive geographical change. And it’s been going on for three years and nobody has said stop,” Ms. Doyle said. She continued:

“It’s not just what we cut. And it’s not just what we build. It’s what we plant and what we change. It impacts all the people on the point who are already homeowners and taxpayers who bought and paid to live there.

“We picked one flavor. We’re there because we wanted a farm-y grassland plain. And it’s been that forever. And someone came in, and I don’t think they meant badly, and they did this, and nobody said ‘wait.’”

The Norman Foster Foundation was not represented at the meeting.

Surrounded by trees, the single-story building is not readily visible, but it is made primarily of wood with minimal steel portal frames, according to the description on the foundation’s website. Its southern face is lined with solar panels.

“(I)ts simple monopitch shape recalls barn-like structures in the New England tradition . . . Over time, the external cedar will weather with a silvery patina which relates to the expressed grey painted structure. This combination of greys is typical of Vineyard buildings that visually recede into the landscape,” the description continues.

The building is located on a 3.8-acre parcel on Pond View Farm Road on the eastern shore of the Tisbury Great Pond that was included in the 2011 sale of the 28-acre Blue Heron Farm to Mr. Foster and his wife, Lady Elena Ochoa Foster. Most of Blue Heron Farm is located on the pond’s western shore. Formerly owned by the late Anthony Fisher and his wife Anne, who died in an airplane crash in 2003, Blue Heron Farm later served as a summer vacation retreat for President Obama during his first three years in office.

In November 2018, Vineyard architect Chuck Sullivan appeared before the West Tisbury planning board on behalf of Fosters seeking approval for a single-family residence on the unbuilt eastern shorefront lot.

According to official minutes of the meeting, the owners intended to build a three-bedroom house for guests, who would mostly travel to and from their home across the pond.

Speaking to the Gazette by phone Thursday afternoon, Mr. Sullivan said the town had not flagged any problems with the building project. “It’s a single family house in a residential district — all the proper permits were issued and all the guidelines and rules regulations were followed,” he said.

Monday’s planning board discussion was prompted by a letter signed by Marilyn and Warren Hollinshead and Ted and Betsy Wheeler, who enumerated their concerns and sought guidance on who was responsible for monitoring the site.

“What recourse do the neighbors and the town have in case the residential requirement is flaunted and the building is used for a commercial purpose?,” the letter asked in part. “It is distressing to feel that the town of West Tisbury has given little attention to this construction.”

Planning board members listened sympathetically to neighbors’ concerns, noting they had no enforcement authority and urging them to take environmental complaints to the town conservation commission, according to a recording of the public meeting made available to the Gazette.

The board also unanimously agreed to send a letter to the building inspector to look into whether the construction violates the zoning bylaw, as it is located in a residential zone.

“In terms of our jurisdiction, the only thing we have control over is the business use in a residential area. And we have not approved a business in that residential area and we have not been approached or even asked to approve it,” said planning board member Bea Phear.