A leak in a primary residence is bad. A leak in a vacation home that's empty from May through October is catastrophic. We've responded to second homes in Boca, Naples, Palm Beach, and Fort Lauderdale where a refrigerator water line failed in June and the owners walked in the first week of November to find every drywall sheet on the first floor sagging, every cabinet swollen, hardwood cupped beyond repair, and mold visible on every wall.
Long absences in South Florida humidity multiply every risk. The good news is that the problem is solvable — the right shutoff, the right monitoring, and the right maintenance routine reduce the probability of a catastrophic water event by an order of magnitude. This guide is the playbook we wish every second-home owner had before their first summer away.
Why empty homes fail in South Florida
Three things conspire against an empty house here:
Heat and humidity continue at full strength. A house closed up with the AC dialed to save mode runs at 80% indoor humidity. Wood expands. Caulking degrades faster. Adhesives soften. Mold germinates anywhere there's a moisture source.
Slow leaks have time to escalate. A toilet running 24 hours a day for 90 days dumps thousands of gallons. A hairline pinhole in a copper line that would dry on a wall in an occupied home turns into a black-mold colony in an empty one.
There's no one to notice. Every leak we fix in an occupied home was caught by someone hearing a drip, smelling something off, or noticing a stain. None of that happens in a closed-up second home.
The protection plan addresses each of those three.
Smart water shutoff: the single best investment
The most cost-effective protection a vacation-home owner can make is a smart whole-home water shutoff. These devices install on the main supply line where it enters the house and either:
- Detect anomalous flow (water running at unusual times or in unusual volumes) and automatically shut off, or
- Pair with leak sensors placed throughout the house and shut off when any sensor reports water.
The two leading models in South Florida second homes:
- Flo by Moen (now Moen Smart Water Shutoff). Plumbed in-line. Learns your normal water use, alerts your phone, and can shut off automatically.
- Phyn Plus. Similar concept. Some users find the leak signature detection more accurate.
Both are roughly $700–$900 installed by a plumber. The avoided cost of a single bad leak event in an empty home is 10x to 100x that.
If you do nothing else from this guide, install one of these.
A layered leak detection setup
A good layered setup for an empty South Florida home:
Layer 1: Smart whole-home shutoff (above).
Layer 2: Wireless leak sensors at the high-risk points — under every sink, behind the refrigerator, behind the washing machine, under the dishwasher, in the AC closet drain pan, behind the toilet, and at the water heater. The sensors are usually free or bundled with the smart shutoff, and they pair to it.
Layer 3: A separate cellular-monitored alarm system that includes water sensors. Why a separate system? Because if power or Wi-Fi goes down, the smart shutoff loses connectivity. A cellular system keeps reporting.
Layer 4: A scheduled drive-by inspection. We'll cover this below.
The pre-departure shutoff checklist
A 30-minute checklist before you leave for the season, in this order:
1. Turn off the main water supply. This is the single highest-impact action. The smart shutoff usually has a manual override — confirm the valve is closed.
2. Open one or two faucets to bleed pressure off the lines so any small failure isn't sitting under pressure.
3. Turn off the water heater. Gas valve to vacation or pilot. Electric heater breaker off.
4. Close all toilet supply valves. Belt and suspenders — even with the main off, this prevents any residual line pressure from running water if a flapper fails.
5. Set the thermostat to 78°F (or whatever your insurer requires) and a humidity setting if your thermostat supports it. Many South Florida insurance policies require occupancy or a specific thermostat setpoint to maintain coverage on long absences — check your policy.
6. Inspect all visible plumbing fittings. Tighten anything obviously loose. Replace anything visibly corroded.
7. Take photos of every room and the exterior. Date-stamped. Establishes a baseline if anything happens.
8. Confirm your insurance policy is in force and that any vacancy clauses don't kick in.
What to do about the AC
The AC is your biggest tool against humidity damage in an empty home, and the AC condensate drain is one of your biggest leak risks.
- Service the AC right before you leave. Have a tech flush the condensate line, clean the coil, verify the float switch, and replace the filter.
- Run the AC through the season. Don't turn it off. Set it to 78°F or what your insurance requires.
- Add a smart thermostat that reports humidity and lets you adjust remotely.
- Install a float switch on the AC condensate line if you don't have one. This shuts the AC down rather than letting an overflowing pan dump water on your ceiling.
- If the AC closet is interior (no exterior wall), consider a leak sensor wired to the smart shutoff in the AC pan.
A working AC condensate drain plus a float switch plus a leak sensor is layered protection that catches almost every AC failure mode.
Maintenance items that prevent disasters
The least-glamorous, most-effective preventive items:
- Replace flexible supply lines on washing machines, dishwashers, refrigerators, and toilets every 5–7 years. The factory rubber lines are the #1 cause of catastrophic failures in vacation homes.
- Pressure-regulate the house. South Florida municipal water pressure varies — some areas push 80+ psi, which slowly kills fittings. Install a pressure-reducing valve set to 55–65 psi.
- Replace the water heater on schedule. Gas water heaters last 8–12 years; electric 10–15. A water heater that fails while you're away can dump 50 gallons immediately and continue to feed water through the supply line until something shuts it off.
- Have a plumber camera the main sewer line every 3–5 years. Tree roots and corrosion in older South Florida lines lead to sewer backups, and an empty home that backs up sits in sewage for weeks.
- Check caulking and grout in showers and around tubs annually. Shower leaks into framing are quiet, slow, expensive failures.
Have someone check the house
A scheduled in-person inspection while you're away catches things smart sensors miss. Either a property manager, a trusted neighbor, or a paid weekly service. What they should check:
- Front door, back door, garage entry — any visible water on floors.
- Each bathroom — toilet not running, no smells, no visible water.
- Kitchen — refrigerator pulled out a few inches once a month to check the icemaker line.
- AC closet — drain pan dry, float switch hasn't tripped.
- Around the exterior — irrigation working as expected, no pooling water against the foundation.
- Pool equipment — visible leaks at pumps and filters.
- Smell test — anything musty in any closed-up room.
A 20-minute weekly walkthrough catches a lot.
Insurance considerations
Insurance for second homes in South Florida is more complicated than primary residences. A few things to verify:
- Vacancy or occupancy clauses. Most policies define a home as vacant after a certain number of consecutive days unoccupied, and coverage may be reduced or excluded.
- Thermostat and shutoff requirements. Some insurers explicitly require a smart shutoff for second homes. Some require a specific thermostat setpoint.
- Mold coverage cap. Standard policies cap mold at $10,000 — a long-running leak in an empty home blows past this fast. Buy extra mold coverage if your home is empty for more than 30 days at a time.
- Sewer backup rider. Always worth it on a primary, and especially worth it on a second home where you can't catch the backup early.
- Flood insurance. Separate from homeowners. South Florida coastal areas almost always need it.
Have this conversation with your agent every year, not just when you buy.
What to do if you arrive to a flood
If you walk into a vacation home that's been leaking for weeks:
1. Don't turn on lights or HVAC. If water is anywhere near electrical, kill power at the main breaker before you enter further.
2. Don't move things or clean up before documenting. Photo and video everything before any cleanup. This documentation is what saves your insurance claim.
3. Call a restoration company first, your insurance carrier second. The restoration company knows what to document for the carrier and how. A long-vacancy water event is the kind of claim that goes wrong without good documentation.
4. Don't try to assess mold yourself. A house that's been wet for weeks in Florida humidity has mold. A professional remediation team handles containment so the cleanup doesn't spread spores to unaffected areas.
5. Don't sign anything in the parking lot. Florida had abusive Assignment of Benefits problems where contractors took over claims at vulnerable moments. A reputable restoration company will work directly with your insurer without an AOB.
When to call RestoFlo
If you're a snowbird, a part-time resident, or a vacation rental owner with a property in South Florida, we can help with both prevention and response. We do pre-departure inspections, install or coordinate smart shutoff systems, perform drive-by checks, and respond to active emergencies anywhere in Miami-Dade, Broward, and Palm Beach counties.
24/7 emergency line: (754) 289-4815.
