This historic mansion in Cheltenham could be demolished to make way for 216 housing units.

The property has been called “the best example of an early 20th century estate” in the vicinity of the Route 309 Road Improvement Project “and one of the best in the area” by the Pennsylvania Bureau of Preservation.

Its importance is highlighted in Cheltenham Township’s open space and comprehensive plans.  But it’s not listed on the National Register of Historic Places.

In the 1890s, it was home to former Pennsylvania Railroad vice president John Clark Sims, and following Sims’ death in 1901, the property was bought by Philadelphia socialite Isaac T. Starr, who commissioned the renowned architect Charles A. Platt to build a Georgian mansion on the property during World War I. Elizabeth Biddle Shipman designed the garden.

The 43-acre estate, straddling Springfield and Cheltenham townships, has since been divided into smaller parcels, and now Blue Bell-based development firm Hansen-Lloyd is planning to build an age-restricted living community for baby boomers on 10.7 acres.

No one knows exactly how many units Hansen will build – the first meeting between the development firm and the townships was scheduled for Monday morning – but a group of area residents is already organizing to ensure that the mansion and other historic elements will be integrated into Hansen’s plans.

As of Friday, March 20, the group had 80 members registered on its Web site, savelaverockhill.com. Over the weekend, 15 volunteers joined Save Laverock Hill founder Scott Laughlin in distributing flyers to 750 households in the vicinity of the Hansen property.

“Inner-suburban, age-restricted housing is a need in this area,” Laughlin said in a phone interview. “The overall concept is not completely against the interest of the people.”

Still, Laughlin said he was concerned with Hansen’s initial sketch plan.

“The initial sketch plan does not preserve the mansion or gardens,” he said. “The developers said they would preserve the historic building if density shifted to Springfield. There are hurdles in Cheltenham that preclude the plans as presented.”

The tentative sketch plan of the Laverock Hill development shows the location of eight proposed four-story buildings west of Willow Grove Avenue in Cheltenham Township. This proposal calls for 216 age-restricted housing units.

The Montgomery County Planning Commission’s report to Cheltenham Township defines the problem well:

“The proposed plan would create a new main entrance to the site off Willow Grove Avenue, approximately 450’ north of Newbold Lane, and would widen the existing driveway to the main house to provide secondary site access. The proposal is for eight four-story buildings … with 27 units in a building, for a total of 216 age-restricted dwelling units.”

The tentative sketch plan also called for 388 parking spaces, both above and underground, and a 2400-square-foot community building in the heart of the development.

“The proposed plan would raze the Laverock Hill house, remove the majority of the existing trees and plantings on the property, and regrade much of the existing slope of the land,” according to the report. “The proposed plan may also require the demolition of another existing home to the rear of the development area, which is located on the Springfield Township portion of the overall 43-acre tract.”

That’s the part that caught Laughlin’s attention when the report was released last month.

“I have a personal passion for historic architecture,” he said.

The problem literally hits close to home for Laughlin, who lives in one of the carriage houses built on Laverock Hill in 1917.

“Our greatest concern is why do they have to tear down a beautiful structure? Why can’t they keep the garden and mansion for a clubhouse?”

Laughlin said that increased traffic and density would also be a concern.

The planning commission report raises those issues as well:

“The current zoning of the Cheltenham Township portion is R-3, Medium-Density Residential, permitting by-right development of single-family detached homes on minimum 20,000 square foot lots, and permitting town homes in Planned Cluster Development as a Conditional Use…

“The Age-Restricted Overlay District may also be applied to this parcel at the discretion of the Township, provided that it meets all of the requirements for the overlay and for special exception use. Cheltenham Township has a Preservation Overlay District, which would apply to development on this site; however, it appears that the proposed community is permanently restricted to persons aged 62 or older.”

The planning commission has asked the developers to clarify the age restriction, which has been pitched at both 55-plus and 62-plus, because the Cheltenham zoning code provides exemptions only for the latter. The plans would have to be redesigned for a 55-plus age-restricted community in accordance with Cheltenham’s preservation overlay code.

In that case, “density would be determined by a By-Right Yield plan; existing structures and natural features would have to be preserved; new structures would need to be relocated a minimum of 100 feet from the preserved structures on the site; maximum height would be three stories of 40 feet; no more than eight units would be permitted in a building; and other requirements apply...”

In other words, Hansen and Cheltenham Township have to hammer out the details.

“The issue is very much in a tentative stage,” Cheltenham Township manager David Kraynik said in a phone interview on Friday. “It’s a bit premature to talk about. They haven’t submitted anything official.”

Plans for an additional access point to the development and a 50-foot rear setback to accommodate parking requirements would require the cooperation of Springfield Township — hence Monday’s meeting.

“Springfield, like many of our neighbors, is fairly well built out and preservation of green space is a high priority,” said Douglas J. Heller, one of the township’s seven commissioners, in an e-mail on Friday. “I am personally very interested in historic preservation and retaining the historic character of our neighborhoods. Our built environment helps to define who we are and as a commissioner I take seriously my charge to preserve our quality of life by fighting to retain our historic resources and green spaces.”

Nonetheless, Heller said he was open to the developer’s suggestions.

Scott Laughlin and his growing group of supporters will no doubt be offering their suggestions as well to Heller and others.

“They’re pretty well organized,” said Hannah Mazzaccaro, who drafted the planning commission’s report for Cheltenham Township. “I’m not sure what legal standing the residents have, but right now people are generally concerned with the size of the development.”

If Cheltenham Township applies the age-restricted overlay, Mazzaccaro said, Hansen could build 300 units by right.

If the zoning issues are not resolved in discussions between the developer and both townships, Mazzaccaro said there could be litigation.

The future of Laverock Hill is fraught with contingencies. The community waits with baited breath.

The developer’s attorney, Ross Weiss of the law firm of Cozen O’Connor, did not return a call for comment.