Northern New Jersey is getting cooked this week. We’re talking triple-digit heat indexes, nights that barely dip below 80, and AC units across Morris County running like they’re training for a marathon. If you own a home up here, this isn’t just a comfort issue — it’s a property protection issue.
I’ve seen what extended heat does to homes. Cracked driveways, blown AC compressors, warped siding, foundation stress from dried-out soil. Most of it is preventable if you know what to look for and act before the damage is done. Here’s the playbook.
Keeping Your House Cool Without Killing Your Electric Bill
Your first instinct is to crank the AC down to 65 and hide. I get it. But that’s a fast track to a $400+ electric bill and an overworked system that might quit on you mid-week when you need it most. Here’s what actually works.
Work With Your Thermostat, Not Against It
Set it to 76–78 during the day. I know that sounds warm, but combined with ceiling fans (which make a room feel 4–6 degrees cooler), it’s comfortable and your system won’t be running nonstop. Drop it to 72–74 at night for sleeping. If you have a programmable thermostat, set it to bump up a couple degrees when nobody’s home. Every degree below 78 adds roughly 3% to your cooling costs.
Block the Sun Before It Gets Inside
Close your blinds and curtains on south- and west-facing windows during peak hours (11am–5pm). Blackout curtains can drop room temperature by 10–15 degrees compared to bare windows. That’s free cooling. If you have older single-pane windows, this matters even more — those things let heat pour in.
Use Your Fans Strategically
Ceiling fans should run counterclockwise in summer (looking up at the fan, blades should spin counterclockwise). This pushes air down and creates a wind-chill effect. Put a box fan in a window facing outward on the shady side of the house at night to pull hot air out. Turn off fans in empty rooms — fans cool people, not rooms.
Don’t Create Heat Inside
Your oven is a 400-degree box in the middle of your house. Skip it. Grill outside, use a microwave, or eat cold meals during the worst days. Same goes for your dryer — run it at night or hang dry when you can. Even your dishwasher throws off significant heat. Run it overnight.
Quick win: Switch any incandescent bulbs to LEDs. Incandescents convert 90% of their energy to heat. In a house with 30 bulbs, that’s like running a small space heater in every room.
Protect Your AC Before It Gives Out
Your air conditioning system is working harder this week than it will all year. A breakdown during a heat wave means you’re waiting 3–5 days for a technician because every HVAC company in North Jersey is slammed. Prevention is everything.
Change Your Filter Right Now
If you haven’t changed your air filter in the last 30 days, do it today. A dirty filter makes your system work 15% harder. During extreme heat, I recommend checking it every two weeks. A clean $8 filter can save you a $300 service call.
Clear the Area Around Your Outdoor Unit
Go outside and look at your condenser (the big box with the fan). It needs at least 2 feet of clearance on all sides. Cut back any weeds, bushes, or debris. If mulch or grass clippings are piled around it, clear them. Airflow is everything. While you’re there, gently spray the fins with a garden hose (not a pressure washer) to knock off dust and dirt.
Don’t Set It Too Low
Here’s what happens when you set your thermostat to 65 in 100-degree heat: your system runs continuously, the evaporator coil can freeze, and then you get no cooling at all. Most residential AC systems are designed to cool about 20 degrees below outdoor temperature. In 100-degree heat, 78–80 is realistic and sustainable.
$8 filter — can save you a $300 emergency service call
15% — how much harder your AC works with a dirty filter
3–5 days — average HVAC wait time during a NJ heat wave
Property Damage to Watch For
Heat doesn’t just make you uncomfortable. It puts stress on your house in ways that can turn into expensive repairs if you’re not paying attention.
Foundation and Soil
Extended heat dries out the soil around your foundation. When clay soil shrinks, it pulls away from the foundation walls, creating gaps. When rain finally comes back, water rushes into those gaps and pools against your foundation. I’ve seen this cause cracking, settling, and water intrusion in basements across Boonton and Parsippany. The fix is simple: run a soaker hose around your foundation perimeter for 15–20 minutes every few days during the heat wave. Keep the soil consistently moist — not soaked, not bone dry.
Driveway and Walkway Cracks
Asphalt and concrete expand in extreme heat. If your driveway already has small cracks, heat can turn them into big ones fast. There’s not much you can do during the heat wave itself, but this is your reminder to seal-coat your driveway before winter. Existing cracks should be filled with a flexible sealant — rigid fillers will just crack again with the next temperature swing.
Deck and Exterior Wood
Wood decks, fences, and trim dry out and can warp, split, or crack in sustained heat. If your deck hasn’t been sealed or stained in the last 2–3 years, this heat is accelerating the damage. After the heat wave passes, inspect for new cracks or warping and plan to reseal before fall.
Siding and Paint
Vinyl siding can warp in extreme heat, especially if it’s dark-colored and on a south-facing wall. If you see buckling or waviness, don’t try to push it back — it should return to shape as temperatures drop. If it doesn’t, that section may need replacement. Painted surfaces on the south and west sides take the most abuse. Peeling or bubbling paint during a heat wave is a sign the surface wasn’t properly prepped or the paint is at end of life.
Roof Stress
Your roof is absorbing the worst of it. Asphalt shingles can hit 150+ degrees in direct sun. Prolonged heat accelerates aging, curling, and granule loss. You’re not going up there to inspect it during a heat wave (and you shouldn’t), but once things cool down, take a look from the ground for any curling or discoloration. If your roof is 15+ years old, this kind of heat wave is a good trigger to get a professional inspection.
Don’t Forget Your Landscaping
Mature trees add real value to your property — anywhere from $1,000 to $10,000 depending on species and size. Losing a tree to heat stress is losing money.
- Water trees deeply (30–45 minutes with a slow hose at the drip line) every 5–7 days during extreme heat. Shallow daily watering is worse — it encourages surface roots.
- Mulch around tree bases 2–3 inches deep (but not touching the trunk) to retain moisture and regulate soil temperature.
- New plantings from this spring are the most vulnerable. Water them every 2–3 days. They haven’t established root systems deep enough to handle this.
- Water your lawn early morning (before 8am) if you’re going to water at all. Watering in the afternoon sun wastes 30%+ to evaporation. Watering at night can promote fungal growth.
Check on Your Pipes
This one surprises people, but extreme heat can affect plumbing — especially if you have exposed pipes in crawl spaces, attics, or along exterior walls that get direct sun. PVC pipes can soften and sag in extreme heat. Copper pipes expand. The joints and connections are where problems show up first. If you notice any new drips or reduced water pressure during the heat wave, don’t wait on it.
If you’re selling this summer: A heat wave right before listing can expose issues that were invisible in cooler weather — AC problems, foundation cracks, deck damage. Get ahead of it. I walk every listing with a contractor’s eye before we go live. That’s the kind of thing that prevents a deal from falling apart at inspection.
The Bottom Line
Heat waves are temporary, but the damage they cause doesn’t have to be permanent — as long as you’re proactive. Most of what I’ve listed here takes 30 minutes and costs almost nothing. The homeowners who do this stuff quietly protect tens of thousands in property value. The ones who don’t find out about it when their AC dies at 2am or their foundation cracks in September.
Stay cool out there, North Jersey. And if you’ve got questions about any of this — whether you’re prepping to sell, just bought, or have been in your place for 20 years — reach out. This is what I do.