The Clement Stone Mansion sat on Sheridan Road for 111 years before anyone found a way to actually stop its demolition. Nobody did. In October 2023, the new owners of the 1912 Spanish Mission Revival estate filed a demolition permit. The village's Landmark Preservation Commission spent the next thirteen months reviewing it, ordering a historic study, delaying the permit for the maximum time the law allows, and asking the owners twice to reconsider. Then, on schedule, the house came down anyway. If you're weighing a lakefront purchase in Winnetka right now, that timeline is the most useful fact in this whole story, because it tells you what historic review actually does: it buys time, not protection.
The house that was never going to survive
Built for Lena Gilmore in 1912 and known for decades as the Clement Stone House, the mansion at 445 Sheridan Road went on the market in 2022 and sold the following year for $12.3 million to Shiraz and Vijay Kotte, both health care executives, Vijay is the CEO of GoHealth. When they filed for demolition that October, the Winnetka Historical Society flagged the house as architecturally significant, which triggered a Historic and Architectural Impact Study. The study confirmed the significance. The Landmark Preservation Commission voted to delay demolition for 270 days, the longest delay the ordinance allows. One commissioner resigned in protest after the vote, saying she was disappointed at not being able to save the house.
None of it mattered in the way most buyers assume it would. The Winnetka Historical Society said it plainly in its own history of the property: neither the society nor the village has authority to prevent the demolition of a historic building. The delay expired on November 1, 2024. Demolition proceeded. Construction on the replacement, a 28,690-square-foot house with an estimated $10 million construction cost, is now underway on the same lot.
What "historic" actually buys you in Winnetka
Winnetka's demolition ordinance was tightened in 2021 after a run of high-profile teardowns, including the 1861 Thomas Bassett House on Maple Avenue, one of the oldest homes in the village, and a 2020 fight over 740 Ardsley Road that only ended when the owners voluntarily withdrew their permit under community pressure. A village trustee at the time called the teardown pace "out of control." The 2021 amendments extended the maximum demolition delay from a shorter window to 270 days and added a 20 percent floor area bonus for owners who preserve a home the commission finds significant, an incentive meant to make renovation pencil out against a teardown.
The mechanics work like this. If a home isn't found historically or architecturally significant, the review typically takes 30 to 60 days. If a study is required but the home still isn't found significant, expect 60 to 120 days. If the home is found significant, the commission can delay the permit up to 270 days, full stop. There is no fourth outcome where the village says no. The ordinance was built to slow a demolition down long enough for a buyer, a preservation group, or a change of heart to intervene. It was never built to require one.
That distinction matters for anyone pricing a historic Winnetka property. A protected-sounding designation is really a clock, not a lock. Budget for it as a timeline risk on your closing and construction schedule, not as a reason to assume the house will still be standing when you're ready to build.
The gate that has nothing to do with history
Separate from historic review, and arguably more consequential for anyone buying directly on the water, is Winnetka's 2024 bluff protection ordinance. It has nothing to do with a house's age or architectural pedigree. It cares about one thing: where your lot sits relative to the lake's steep slope zone, measured against an ordinary high-water benchmark the village set at 581.5 feet under U.S. Army Corps of Engineers standards.
The ordinance grew directly out of private equity billionaire Justin Ishbia's construction at 205 Sheridan Road, a $77 million, 68,000-square-foot compound built by combining several lakefront parcels, which included leveling a stretch of bluff and drew sustained neighbor opposition over erosion risk. The village council passed the new steep-slope rules 5-0 in February 2024, restricting how much of a lakefront lot's table land and bluff face can be built on, regardless of what stood there before.
An architect's case study submitted to the council during debate over the ordinance, using a 1.25-acre bluff-top parcel that had sold in 2020, found the new rules would cut the buildable area on that lot by 37 percent, push any new house 56 feet farther from the lake, and eliminate walk-out basement rooms with lake views entirely. That's not a hypothetical for every Sheridan Road buyer. It's the baseline you're now negotiating against.
The permit record so far
The clearest evidence of how the ordinance plays out in practice comes from a Real Deal review of village permit files: of at least eleven applications for construction in the steep slope zone filed since February 2024, only four had been approved as of January 2026. Two homeowners withdrew their applications outright. Five were still working through review, one more than a year after submission. Reviewers rejected a retaining wall design for having a flat top that effectively extended a backyard into the bluff zone, and blocked a terrace replacement for extending four feet past its original footprint.
Jena Radnay, a lakefront broker who has worked with clients navigating the ordinance, put it bluntly to The Real Deal: they are "making it as hard as possible to do an improvement." Winnetka's village attorney, Peter Friedman, has taken the opposite position publicly, saying the ordinance has clear requirements and that construction has continued to move forward under it. Both things can be true. The rules are legible on paper and slow in application, which is exactly the kind of friction that shows up in a closing timeline rather than a listing description.
The dollar impact isn't theoretical either. A Cook County-based appraisal cited in a federal lawsuit found that one Taylorsport Lane estate lost 64 percent of its pre-ordinance value, dropping from $7.54 million to $2.69 million, after roughly 17,700 square feet of its lot became unbuildable. A Sheridan Road owner told village officials a land use analyst found the rules cut his buildable land by 41 percent.
Why this is now permanent, not temporary
If you were waiting to see whether courts would unwind the bluff ordinance before factoring it into a purchase decision, that window has closed. A group of lakefront owners, including private investors and former Abbott and United Airlines executives, sued the village in 2024 arguing the rules amounted to an unconstitutional taking of their property. A federal judge dismissed that claim in October 2025 for lack of proof of actual loss. The plaintiffs refiled with new appraisal evidence in December 2025, claiming $16 million in combined lost value across four estates and warning the number could reach into the hundreds of millions if applied across all 112 affected lakefront parcels.
That refiled case was also dismissed. Federal District Judge LaShonda Hunt rejected the plaintiffs' constitutional claims again, and the village has said it is hopeful the litigation is over. Whatever happens with any remaining state law claims, the practical answer for anyone evaluating a Winnetka lakefront property today is that the ordinance is not going anywhere in the near term. Underwrite your offer accordingly.
What this changes about how you shop Sheridan Road
Two separate approval processes now govern any teardown-rebuild on Winnetka's lakefront, and they answer completely different questions. Before you write an offer on a lakefront or historic-adjacent property, it's worth asking for documentation on both fronts:
- Has the home ever been reviewed by the Landmark Preservation Commission, and if not, what's the realistic range for a first-time demolition review, 30 days or 120?
- Does the lot include any steep slope zone acreage, and if so, has a survey established where the 581.5-foot ordinary high-water line falls on this specific parcel?
- If prior owners applied for steep slope permits, what was approved, what was rejected, and how long did review take?
- Does the purchase price reflect pre-ordinance assumptions about buildable square footage, or has it already been adjusted for the reduced footprint?
None of this means Winnetka's lakefront has stopped being one of the most sought-after stretches of shoreline on the North Shore. Ishbia's estate, the Clement Stone rebuild, and the steady flow of new construction on Sheridan Road prove buyers are still willing to pay for it. It does mean the math behind a lakefront teardown now runs through two separate village processes with two separate timelines, and treating them as one hurdle instead of two is how a buyer ends up surprised at the closing table.
A short FAQ
Does landmark or historic status protect a Winnetka home from demolition? No. Historic or architectural significance triggers a study and can delay a demolition permit up to 270 days, but the village has no legal mechanism to deny the permit outright once that period ends.
Does the bluff ordinance apply to homes that aren't directly on the water? It applies specifically to the steep slope zone along Lake Michigan, defined relative to the 581.5-foot ordinary high-water benchmark. Homes outside that zone are not subject to the 2024 restrictions, though they may still fall under standard Winnetka zoning and demolition review.
How long should I plan for if I want to tear down and rebuild on Sheridan Road? Budget for both processes separately. Historic review alone can run 30 to 270 days depending on findings. Steep slope permit review has taken over a year in at least one documented case still pending as of January 2026. Treat the combined timeline as a material part of your carrying cost, not an afterthought.
If you're weighing a purchase on Winnetka's lakefront, or wondering what these rules mean for a historic or blufftop property you already own, the details in your specific parcel's survey and permit history matter more than the headlines. Summerville Partners can walk through what your property or target address actually faces before you write an offer or list. Request a Free Home Valuation to start that conversation.
