A Charleston second home sitting empty from October to April isn't going to freeze solid, but it isn't zero-risk either. The Lowcountry has handed us hard freezes in recent winters that caught snowbirds flat-footed — burst pipes on Isle of Palms, flooded ground floors in Mount Pleasant, and HVAC systems that quietly ran themselves into failure while owners were in Pennsylvania. Here's the walkthrough I give every seasonal client before they lock the door for the winter.

I've helped a lot of snowbirds buy, sell, and manage second homes across the Charleston area over 20+ years. The ones who get burned on return trips almost always skipped one of the items below.

Plumbing — The Single Biggest Risk

Charleston pipes typically don't freeze in a normal winter night. The problem is the three or four nights per winter that drop into the low 20s or teens. Pipes in attic spaces, exterior walls, crawl spaces, and outdoor hose bibs are the usual casualties.

Before you leave:

  • - Shut off the main water supply (know where your valve is before departure day — don't be hunting for it the morning you fly out)
  • - Drain outdoor spigots and disconnect every hose
  • - Insulate exposed pipes in the attic, garage, and crawl space
  • - If you leave water on, install freeze-protection drip switches or a smart leak detector
  • - Consider a smart water shutoff valve that triggers on leaks

On homes near marsh or on raised foundations, the crawl space is the number-one source of winter plumbing failures. Vent closures and insulation here pay for themselves the first winter.  

Winterizing Your Charleston Second Home Before You Head North

HVAC — Don't Just Turn It Off

Here's what nobody tells you. Turning the HVAC completely off in a Lowcountry winter is a mold invitation. Humidity sits around 70%+ on mild winter days, and without air circulation plus some conditioning, mold grows on walls, inside closets, and behind furniture.

What to do instead:

  • - Set the thermostat to about 60°F in winter — enough to prevent freezing and dehumidify
  • - Install a smart thermostat (Nest, Ecobee) you can monitor and adjust from your phone
  • - Change the filter the day you leave, and set a reminder to have someone swap it monthly
  • - Schedule a service tune-up to catch coil issues before you leave town
  • - Keep interior doors open and closet doors cracked so air circulates

Pest Control

Empty homes are a magnet for mice, roaches, and (in low-elevation areas) wildlife. Spring returns in April to a mouse-chewed sofa are more common than you'd think.

  • - Deep clean the kitchen before leaving — crumbs, pantry food, pet food
  • - Store pantry items in sealed containers or clear everything out
  • - Have a pest control company do a pre-departure treatment and set traps
  • - Seal gaps around utility entries, dryer vents, and crawl space openings
  • - Keep gutters cleaned — standing water invites mosquitoes right into spring return

Security and Monitoring

Even a quiet neighborhood is a different animal when half the block is empty for the winter. Insurance carriers also increasingly ask about monitoring on seasonal homes.

  • - Install smart video doorbell and cameras at main entry points
  • - Use a monitored alarm system — the monitoring fee is cheap compared to a claim
  • - Set lamps on smart timers to vary daily
  • - Suspend mail and newspapers; use a USPS vacation hold or forwarding
  • - Alert a trusted neighbor and your HOA (if applicable) that you'll be gone
  • - Keep landscaping maintained — overgrown yards signal vacancy

Insurance Review Before You Go

Call your insurance agent before you leave town — not after you've landed in Michigan. Make sure your policy covers:

  • - Extended vacancy (standard policies may not — ask specifically)
  • - Water damage from frozen pipes
  • - Theft from an unoccupied dwelling
  • - Wind and flood coverage if you're near the coast

If you're in a Kiawah Island, Seabrook Island, or Folly Beach flood zone, confirm your NFIP or private flood policy is active through the winter.

The Hire-It-Out Checklist

Second-home owners who don't have family nearby almost always benefit from paid property watch service. Expect to pay $75–$200 a month for someone to:

  • - Walk the property every week or two
  • - Check for leaks, HVAC issues, and pest activity
  • - Flush toilets and run water briefly to keep traps full
  • - Rotate lights, blinds, and mail
  • - Send photos and a written report

In the Charleston market, there are several reputable concierge property-management companies that specialize in snowbird clients. Vet by referral and ask for proof of insurance.

Pre-Departure Walkthrough

The day you leave, run this list before closing the door:

  • - Main water valve: off (or smart shutoff armed)
  • - Hose bibs: drained, covered
  • - Thermostat: 60°F, smart-connected
  • - Fridge/freezer: emptied or stocked only with freezer items
  • - Dishwasher and washing machine: run and dried, doors cracked open
  • - Garbage disposal and sink traps: run water, add a splash of mineral oil
  • - All exterior doors and windows: locked, verified
  • - Security system: armed
  • - Mail hold: active
  • - Property watch service: scheduled
  • - Trusted contact: has your keys and phone number

Twenty minutes of discipline at departure saves you an entire spring of problems.

Key Takeaways

  • - Plumbing is the number-one winter risk — shut off main water or install smart leak protection
  • - Don't fully turn off HVAC — set to 60°F and keep air circulating to prevent mold in Lowcountry humidity
  • - Pest control, security monitoring, and insurance review belong on every pre-departure list
  • - Smart home tech (thermostat, cameras, water shutoff) pays for itself the first winter
  • - Hiring a property watch service is cheap insurance for snowbird owners without local family
  • - The last 20 minutes before you lock the door matter more than anything you did the week before
  • - Verify vacancy and flood coverage with your insurance agent before you leave, not after

About Greg Harrelson

Greg Harrelson is Broker/Owner of Century 21 The Harrelson Group and owner of Century 21 Expert Advisor in the Charleston market. With more than 20 years selling coastal Carolina real estate and 500+ Google reviews, Greg and his team of roughly 500 agents help snowbirds and second-home owners across the Grand Strand and Charleston buy, sell, and maintain seasonal properties.