For a lot of our customers, October is when the house comes back to life. The shutters come down, the water gets turned back on, and someone walks through the front door for the first time since spring. It is usually a good day, and it is also the day most of the problems that built up over the summer finally get noticed.
A house that sits empty through a South Florida summer does not stay empty. With nobody walking through, cooking, or running the air conditioning the usual way, pests get months of undisturbed time in the heat and humidity. Most of what you find will be manageable, and some of it is simply the leftover evidence of summer. Knowing where to look first, and in what order, is what separates a quick cleanup from a problem that gets a few more weeks to grow.
Where to start
Check the attic first. Rodent activity is the most consequential thing to find in a closed-up house, and the attic is where it shows.
Run water in every sink, tub, and floor drain. A drain trap that has dried out is an open line to the sewer for cockroaches and drain flies.
If pets lived in the house before you left, expect fleas to appear a few days after you return. Flea pupae can wait out an empty house and emerge once people are moving around again.
Do not sweep up rodent droppings. CDC guidance is to wet them with disinfectant and wipe them up, since sweeping can put particles into the air.
Pests do not leave when you do. In much of the country, a house closed for the season sits through cold weather that slows everything down. Here, it sits through the warmest, wettest months of the year, which is exactly when breeding runs fastest.
Two things work in their favor while you are gone. Nobody is disturbing them, so populations that would normally get noticed early have months to settle in. And if the air conditioning was switched off or set high to save energy, humidity builds up inside, which suits moisture-loving pests and the mold that often comes with them.
Our month-by-month pest calendar shows why the summer you missed is the peak of the pest year here.
The attic is where the most expensive surprises turn up, so it comes first, before you settle in.
Look along the ceiling joists and the top of the insulation for droppings, and for insulation that has been flattened, tunneled, or shredded into nesting material. Check any visible wiring for gnaw marks. Roof rats are the usual culprit in South Florida attics, and a summer without anyone home is plenty of time for a pair to become a family.
If you find droppings, resist the urge to sweep or vacuum them right away. The CDC recommends wearing gloves, spraying droppings and urine with a disinfectant until they are soaked, and wiping them up with paper towels, because sweeping or vacuuming can stir particles into the air you breathe. Then look for how they got in. Our rodent guide covers the roofline openings that matter most.
Kitchens hold the food, water, and warmth that pests look for, and a few months is a long time for them to work undisturbed.
Open the cabinets under the sink and around the stove and dishwasher with a flashlight. Small dark specks along cabinet edges, a musty smell, or small striped cockroaches point to German cockroaches, which may have kept breeding the whole time you were away. Ant trails leading to a forgotten spill or a pet food bag are common too.
Check anything left in the pantry. Flour, cereal, pasta, and dried goods can host small beetles and moths that develop over months, and a sealed box is not much of a barrier. If you find them, the safest move is to throw out the affected items and wipe the shelves down.
This is the step most people skip, and it explains a lot of what they find.
Every sink, tub, shower, and floor drain has a curved trap that holds a little water to seal off the sewer line. Over a long, hot summer that water evaporates, and once it is gone the drain becomes an open passage. Large cockroaches can walk straight up from the sewer, which is why so many returning homeowners find them in bathrooms and laundry rooms. Our guide on American roaches covers why dry drains are such a common entry point.
Drain flies follow the same route, breeding in the film inside pipes that have sat unused. Our drain fly guide explains what to do if they have already appeared.
The fix is simple. Run water in every drain in the house, including the garage, laundry, and any guest bathrooms, to refill the traps. Bathrooms that stayed humid while you were gone may also turn up silverfish, which point to moisture more than to anything serious.
This one catches people off guard, because the house was empty, so where could fleas have come from?
If a dog or cat lived in the house before you left, flea eggs and larvae may have been sitting in the carpet and upholstery all summer. Fleas develop into pupae inside a protective cocoon, and UF/IFAS documents that pupae can stay dormant until they sense vibration and warmth. A house full of people walking around again is exactly the signal they wait for.
That is why fleas sometimes appear a few days after you return rather than on the first day. If you notice bites on your ankles in that first week, our guide on confirming a flea problem covers a quick test.
Dead insects on the windowsills.
Finding a scattering of dead bugs on sills is normal after months away, since insects that get inside head toward the light and die there. It is worth a look before you vacuum, though. A small pile of identical, equal-length wings can be left over from a spring termite swarm, and our guide to telling flying ants from termite swarmers covers what to look for.
The garage.
Cardboard boxes stored in a garage make good shelter and food for cockroaches and rodents. Check corners and along the walls for droppings, and look at the seal along the bottom of the garage door, which is a common way in.
Soffits, eaves, and shutters.
Wasps build under eaves and behind shutters when nobody is around to disturb them. If you see wasps coming and going from the roofline with no visible nest, our guide on wasps in soffits explains what is usually happening. Small grey cases stuck to the outside walls are likely plaster bagworms.
Start by opening the house up and running the air conditioning to bring the humidity back down, since lower humidity makes the house less inviting to moisture pests straight away.
Run water through every drain, then walk the attic, kitchen, bathrooms, and garage in that order. Wash bedding and any linens that sat out, and vacuum carpets and upholstery thoroughly, emptying the vacuum outside afterward.
Skip the bug bombs. Foggers do not reach the places where most of these pests actually live, and our guide on DIY mistakes explains why they tend to scatter a problem rather than solve it.
Keep anything you are unsure about. A bug sealed in a bag or a photo of droppings lets a technician identify what you have in seconds.
The easiest way to have a quieter return is to close the house up with pests in mind. Clear the pantry rather than leaving sealed packages, move cardboard out of the garage, and ask someone to actually go inside now and then rather than only checking the outside. Leaving the air conditioning running at a moderate setting helps keep humidity under control while you are away.
If you have just opened the house and found signs of rodents, roaches, or anything you cannot identify, an inspection tells you what settled in over the summer and what needs attention. Wise House Pest Control offers a free inspection across Palm Beach County, Martin County, and St. Lucie County.
1177 Hypoluxo Rd Suite C-31 Lantana, FL 33462 (561) 727-8239
464 NW Peacock Blvd, Unit 106 Port St Lucie, FL 34986 (772) 783-4300
