Extreme Heat risk in Indiana

Walk into the attic of a 1920s bungalow on the near-east side of Indianapolis in mid-August and the thermometer will read somewhere around 145°F. The air handler is up there. So are the ducts, the joists, and the underside of the roof deck — which is slowly cooking the asphalt shingles from below.

That's the shape of Indiana heat. It's rarely the 118°F desert kind that makes national news. It's 93°F with a dew point in the mid-70s for six straight days, in a state where a lot of the housing stock predates central air. FEMA's National Risk Index puts Indiana at 3 out of 5 for heat — higher than most of the Upper Midwest, lower than the Gulf Coast. That feels about right.

The worst of it tends to concentrate in a few places: Marion County, where the urban heat island adds several degrees over the surrounding farmland; Lake County up by Gary; the Wabash Valley around Terre Haute and Lafayette; the Ohio River bottom near Evansville and Jeffersonville; and South Bend, where older homes with poor attic ventilation take the beating. Rural stretches of Cass, Miami, and Grant counties often have fewer cooling centers and longer ambulance runs.

What actually happens to a house

Heat rarely wrecks a house in one dramatic event. It does it in slow, expensive increments, and then it hands you the bill on the worst possible day.

• Roof and attic. Attic temperatures of 140-150°F are common in a Hoosier July. That heat softens shingle adhesive and bakes the deck. A roof that should have had another decade may not get it.
• HVAC. A condenser that's been marginal all spring fails on the first 95°F afternoon — which is also the afternoon when every contractor in Allen County is booked out two weeks.
• Foundations and basements. Central Indiana's clay soils shrink hard in a dry July, then swell when the rain returns. Hairline cracks turn into seepage.
• Plumbing and electrical. Supply lines in unconditioned crawl spaces expand and stress. Older panels in pre-1960 homes in Muncie, Kokomo, and Terre Haute take a beating from brownouts and surges.

The insurance piece nobody explains at closing

There is no "heat damage" coverage line on a standard Indiana homeowners policy, and no endorsement that turns a dead air conditioner into a claim. Wear and tear, mechanical breakdown, and lack of maintenance are excluded on basically every HO-3 sold in the state. If your 14-year-old compressor dies because it ran eleven hours a day for a week, that's a maintenance bill, not a claim.

What heat does trigger is often covered: fire is a named peril, so a field fire or a house fire started by an overheated fan is a claim. Food spoilage after an outage is usually capped at a few hundred dollars, and often only when the outage traces back to a covered event on your property — not a grid failure three counties away. Here's the split people miss: your homeowners policy handles wind, fire, and hail, while flood — including the basement water that shows up after a drought-then-downpour cycle — is a separate NFIP policy you buy on purpose. Most Indiana basement seepage claims get denied because the water came through the ground, not the sky.

If you only do three things

1. Service the A/C in April. If you have $250 and one free Saturday before the season, that's where it goes — a tune-up and a box fan rigged into the attic hatch. Not a new roof. Not a smart thermostat.
2. Read your spoilage and mechanical breakdown limits before you need them, and ask your agent directly whether an equipment breakdown endorsement is worth it on an aging system.
3. Write down two neighbors' names — one over 70, one who lives alone. The CDC is blunt that heat deaths are largely preventable, and the people who die in Indiana heat waves are usually found indoors, alone, with the windows shut.

Questions we get

Does homeowners insurance in Indiana cover anything during a heat wave?

Sometimes, but not the way people hope. Fire and wind are covered. A failed A/C is not. Spoilage after a power outage is usually a small sublimit, not a full grocery replacement. Read the exclusions page of your policy — it's two pages, and it's the two pages that matter.

I'm buying a house in Marion County in July. What should I ask about?

Ask for the age of the roof, the age of the HVAC system, and the last two summer electric bills. A July bill that looks more like a car payment tells you more about the attic insulation and windows than any inspection report will. Then get a real quote on attic ventilation before you close.

Is Indiana heat actually getting more dangerous?

The trend across the Midwest is toward more frequent and longer heat events rather than one giant spike in peak temperature. Nights are warming faster than days, which matters because a house that can't cool off overnight never resets. We'd rather describe it that way than hand you a specific number we can't back up.

Where to verify this

Don't take our word for any of it. These are the pages we actually use:

• Indiana Department of Homeland Security — state preparedness and emergency guidance.
• National Weather Service — Heat Safety — heat index, warnings, and what the advisories mean.
• Ready.gov — Extreme Heat — practical household checklists.
• CDC — Extreme Heat — who's most at risk and why.

Heat is one of the few hazards where the cheapest fix does the most work — a fan, a tune-up, a knock on a neighbor's door. Start there.