Cos Cob, CT Home Insurance

By Jon Merwin, Founder and CEO

Cos Cob wraps around the mouth of the Mianus River, where the river widens into Cos Cob Harbor before it reaches Long Island Sound. It is Greenwich’s river village: an eighteenth-century saltbox that hosted America’s Impressionists, condos and two-families a short walk from the train, harborside houses near the boatyards, and I-95 crossing high overhead. That variety makes Cos Cob one of the more interesting parts of town to insure.

Our agency, Portsmouth Atlantic Insurance, has been family-owned and independent since 2005, and we are licensed in 10 states. Cos Cob homeowners, condo owners, landlords and drivers get quotes from 40+ carriers through us. Call (203) 859-6858 if you would rather talk it through. Cos Cob clients work with us through our Fairfield office at 1885 Post Road, and by phone, email and online.

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A village built on the river

Cos Cob grew up at the Lower Landing of the Mianus River as a working waterfront village. In 1882 Josephine and Edward Holley moved here and soon opened their old saltbox to summer boarders. From the early 1890s until the 1920s the house was the gathering place of the Cos Cob Art Colony, the first Impressionist art colony in Connecticut, with John Twachtman, J. Alden Weir, Childe Hassam, Theodore Robinson and Ernest Lawson among its early members (Greenwich Historical Society).

That house, the Bush-Holley House on Strickland Road, was built in stages beginning about 1730. It was listed on the National Register in 1988 and named a National Historic Landmark in 1991 (historic designations). The National Register nomination describes it on an elevated site overlooking the Mianus estuary at the head of Cos Cob Harbor, inside the Strickland Road Historic District (NPS). The Greenwich Historical Society bought it in 1957 and runs it as a museum (Bush-Holley House).

The Greenwich hazard plan also lists the Cos Cob Fire House and the Cos Cob Power Station among the town’s historic resources. For homeowners, the takeaway is that many Cos Cob streets mix antique houses with mid-century and newer homes, and the insurance has to fit each one.

A mixed housing stock

About 7,500 people and 2,840 homes are in the Cos Cob census area, per the Census Bureau’s five-year survey for 2020–2024 (B25024). About 1,740 are detached single-family houses. The rest is a real mix: about 410 homes in two-unit buildings, 240 attached townhouse-style units, 200 in three- and four-unit buildings and smaller numbers in larger buildings.

About 800 homes were built before 1940, the largest single group, and the median year built is 1959 (B25034). Renters occupy about 910 homes, roughly a third (B25003). That is a far higher share of rentals and multi-family buildings than in neighboring Riverside or Old Greenwich, and it changes the insurance conversation.

The Mianus River, the harbor and flood risk

The Greenwich hazard mitigation annex treats the lower Mianus as one of the town’s main flood areas. It says the southern reaches of Brothers Brook and the Mianus River Pond have large mapped floodplains and are probably the most at-risk stretches of the river, with 18 repetitive loss properties and road and rail crossings that may strain capacity in a heavy storm.

• The tidal harbor. Below the town-owned Mianus River Dam at Mianus Pond, the river is tidal. The harbor plan describes Cos Cob Harbor as that tidal reach ({a(HMPLAN,”Greenwich Harbor Management Plan”,True)}). Houses along it can flood from Sound surge, not just rain.
• Strickland Brook and Mill Pond. The town studied flooding on Strickland Brook, and the annex lists mitigating flooding in the Cos Cob area and at the Cos Cob Firehouse, which sits across the road from the tidal Mill Pond, as an ongoing action.
• Facilities in the flood zone. Cos Cob School and the Cos Cob dockmaster facility are both on the annex’s list of town facilities inside the 1-in-100-year flood zone.
• Sea level rise. Pair a foot of higher sea level with a 1-in-100-year storm and, by the plan’s estimate, parts of Cos Cob would be under water.

The annex also notes the town has been making significant improvements to the Cos Cob dam. Dams lower risk most of the time, but water released or overtopping in a big storm is still flood under an insurance policy.

How flood coverage works here

Homeowners and condo policies exclude flood. We write new NFIP policies through Selective. FEMA sets the terms: a house can carry up to $250,000 on the building and $100,000 on contents, and a new policy normally waits 30 days before it starts (FloodSmart). Bigger harborside homes often need more, so we also look at Neptune Flood, Flow Flood, CatCoverage, Aon Edge, Beyond Floods and The Flood Insurance Agency, either as a standalone private policy or as excess over the NFIP.

Condo owners have their own wrinkle: the association’s flood policy, if it has one, covers the building, but your unit improvements and belongings need your own coverage. FEMA’s map viewer shows the zone for any address; Greenwich’s panels date from a 2013 revision. Our Greenwich and Westport flood guide and Fairfield County flood guide explain the options in more depth.

Antique and historic houses

Insuring a house from the 1700s or 1800s is mostly a rebuild-cost question. Hand-hewn framing, plaster walls, old-growth trim and slate roofs cost far more to replace than their square footage suggests. Build the dwelling limit on a current rebuild estimate, not what you paid for it, and ask about extended replacement cost and ordinance or law coverage, which helps pay for code upgrades after a loss.

National Register listing alone generally does not restrict a private owner’s changes unless federal funding, licensing or permits are involved, according to the Greenwich Historical Society. Even so, plans, photographs and appraisals of original details make a rebuild estimate more accurate and support a claim. Our article on historic home insurance covers the details carriers ask about.

Homeowners carriers for Cos Cob

Ten Connecticut homeowners carriers are in our lineup: Vermont Mutual, Providence Mutual, Andover, Hanover, Liberty Mutual, Foremost, Stillwater, Cincinnati, National General and Openly. Antique and harborside houses narrow the field, which is why we shop all of them.

If the house calls for a high-value form, Cincinnati and Chubb are the two we quote head to head. They are similar, they compete, and both write homes at any dwelling limit. Openly and National General can also fit homes up to about $5 million. For the larger harborside homes, see our Greenwich high-value home insurance page, and for the rest of town our Greenwich homeowners insurance page.

• Roof, wiring, plumbing and heating updates. Knob-and-tube wiring and old oil tanks are common questions on antique houses.
• How far the house sits from the river or harbor, and what is in the basement.
• Wood stoves and fireplaces, and when chimneys were last inspected.
• Additions and finished space added over the years, so the rebuild cost is complete.

Condos, townhouses and two-families

With so many multi-unit homes, the condo and rental questions come up constantly in Cos Cob. An HO-6 should match the master policy: find out whether the association insures the building as originally built or including unit improvements, what its deductible is, and whether you can be assessed for it. Loss assessment coverage helps when the association bills owners after a large loss. Our condo vs. homeowners insurance guide and the Connecticut condo association page explain how the pieces fit.

If you rent out a unit, a two-family or a small building, it belongs on a landlord policy. Hanover, Foremost, Vermont Mutual, Andover, Liberty Mutual and Providence Mutual write our one- to four-unit rentals, and buildings with five or more units go to Andover, Providence Mutual or Vermont Mutual on a commercial package. Tenants should carry renters insurance.

Trees, wind and outages

Mature oaks and maples line most Cos Cob streets. On March 2, 2018, according to the Greenwich annex, wind on rain-soaked ground toppled several hundred trees across town and cut power to thousands of homes and businesses. It notes the town’s at-risk tree program and Eversource’s trimming along power lines.

For a homeowner, the claims that follow a storm like that are usually wind and tree damage to the roof, fences and cars, and sometimes water damage when a sump pump stops. A generator, a battery backup on the sump, and water backup coverage on the policy are worth discussing before the next one.

I-95, the Post Road and the commute

Cos Cob sits at the I-95 crossing of the Mianus River, along the Post Road (Route 1), and has its own Metro-North station on the New Haven Line (MTA). The highway bridge here has a hard history: on June 28, 1983, a 100-foot span of the eastbound bridge fell 70 feet into the river, killing three people, and the NTSB traced it to corrosion in the hanger assembly (NTSB).

Today the commute is simply busy. Heavy traffic, tight village streets and on-street parking make liability limits and comprehensive coverage worth a look. Our auto insurance quotes run across the same carriers, and a personal umbrella can stack extra liability above the car, the house and any boat. For more on the Stamford side of the Mianus, see our Stamford insurance page.

Boats in Cos Cob Harbor

Cos Cob Harbor holds club and town-permitted moorings, and the town runs a dockmaster facility on Strickland Road. Moorings need a town permit, handled through a waitlist unless you belong to a club with a managed field (Town of Greenwich). For boat insurance we compare American Modern, Foremost Specialty, Hanover, Liberty Mutual and Progressive, and Chubb when the boat is high-value.

Buying a house in Cos Cob

Line up insurance early, especially near the water or in an older house. A few steps keep a closing on schedule:

• Look up the flood zone before you make an offer, and ask the seller for an elevation certificate and any current flood policy. An existing NFIP policy can sometimes be assumed by the buyer.
• If the lender requires flood coverage, a new NFIP policy bought in connection with the loan can start without the usual 30-day wait. Private flood waiting periods vary.
• Ask for the home inspection early. Carriers ask about roof age, the electrical panel, oil tanks and any past water in the basement.
• For a condo, get the association’s master policy declarations and its deductible so the HO-6 can be matched to it.
• For a two-family you plan to rent in part, tell us which unit you will live in and how the other is leased.

Send us the listing and inspection report and we will tell you which carriers fit before you are under deadline. Our Greenwich insurance page covers the rest of town.

Nearby

See our Greenwich overview, the Connecticut high-value home insurance hub and our Connecticut page.

Request a Cos Cob quote

Send us the basics through the form below or the quote page, and we will go to the carriers among our 40+ that suit your home, condo or rental. Request a quote. There’s no obligation to buy. We don’t charge any fees, and you can call (203) 859-6858 any time. What clients say is on our client feedback page: 1,000+ Google reviews and over 2,000 testimonials.

Frequently asked questions

Does the Mianus River flood homes in Cos Cob?

It can. The Greenwich hazard plan says the southern reaches of the Mianus River Pond and Brothers Brook have large mapped floodplains and 18 repetitive loss properties. Below the Mianus Pond dam the river is tidal, so harborside houses can see surge from the Sound as well as high water coming downstream. Check your address on FEMA’s map and tell us which side of the dam you are on.

Is river flooding covered by my homeowners policy?

No. Water rising from a river, a pond, a dam release or the harbor is flood, and homeowners policies exclude it. A separate NFIP or private flood policy is the answer, and this page names the markets we use.

My house is in the Strickland Road Historic District. Does that limit what I can do?

National Register listing by itself generally does not stop a private owner from changing a house unless federal money, licenses or permits are involved, according to the Greenwich Historical Society. For insurance, the bigger issue is cost: matching period materials and craftsmanship after a loss. Build the dwelling limit on a real rebuild estimate and ask about ordinance or law coverage.

Can you insure a Cos Cob condo or two-family?

Yes. Condo owners need an HO-6 that matches the association’s master policy. If you live in one unit of a two-family, many carriers write it as an owner-occupied home; if you rent out the whole building, it goes on a landlord policy with one of the carriers named below.

What do insurers want to know about trees and power outages?

Big trees close to the house, the age of the roof and whether you have a generator. Wind that drops a tree on the house is a homeowners claim. Food spoilage and water backup from a failed sump during an outage depend on the endorsements you carry, so ask us before storm season.

Can you insure my boat in Cos Cob Harbor?

Yes. Have your town mooring permit or slip details, the boat’s length and engine, and your winter storage plan ready, and we will compare the boat markets listed on this page.

How do I start a quote?

The quickest route is the form below; (203) 859-6858 works too. Current declarations pages, the year the house was built and its updates, plus any flood paperwork, speed things up. Request a quote. There’s no obligation to buy.

Sources

• WestCOG multi-jurisdiction hazard plan: Greenwich annex
• Town of Greenwich, Harbor Management Plan (adopted chapters)
• Town of Greenwich, Mooring Permit Application & Guidelines
• Greenwich Historical Society, Art Colony
• Greenwich Historical Society, Bush-Holley House
• Greenwich Historical Society, Historic designations
• National Park Service, Bush-Holley House NHL nomination
• NTSB, Mianus River Bridge collapse (DCA83AH003)
• Building size, Cos Cob (Census table B25024)
• When Cos Cob homes were built (B25034)
• Who owns and who rents in Cos Cob (B25003)
• FloodSmart: NFIP limits and waiting period
• New Haven Line station list, MTA
• FEMA Map Service Center

A general guide for Cos Cob homeowners, renters and drivers, not a quote or a contract and not legal advice. Policy wording, endorsements and carrier underwriting decide what is covered, and the local data above comes from public sources that get revised.