Squirrels, Birds, and Solar Panels

The maintenance page says a lot of systems fail from chewed wiring, not from a missed wash. This page is that problem. Pollen, lovebugs, and the hose stay over there. A low number on a clear day still starts on the monitoring page.

What is actually living under there

A rooftop array sits a few inches off the shingles or the tile. The cavity is dry, dark, and warmer than the open roof. It is a nest site with a built-in supply of things to chew.

Three animals do most of the damage on a Central Florida house.

• Squirrels. The eastern gray squirrel is the common one. Their front teeth grow for life, so they gnaw. A solar cable is an easy chew. They also use tree limbs as a bridge onto the roof.
• Roof rats. University of Florida extension calls the roof rat, Rattus rattus, out by name. It nests up high, not in a burrow, and it can jump about three feet straight up and more than four feet across. A limb or a palm frond that touches the house is a road. The same teeth problem applies. A rat will take the insulation off a wire.
• Birds, especially pigeons where the neighborhood already has them. They are not chewing the copper. They pack nesting material into the cavity and leave droppings on the frames, the flashing, and the glass. Droppings are acidic. Left there, they stain and they can speed up corrosion on metal. They also shade cells the way a leaf does.

A nest full of rodents can draw a snake. That is a reason not to stick a hand under the array, not a reason to start a wildlife project from a ladder. Raccoons are less often inside the low gap and more often in the attic or the soffit. Scratching in the ceiling may be an attic animal, not the panels. Do not assume one problem is the other.

What the chew does

The wires under the panels carry direct current, the kind the modules make before the inverter turns it into household power. When the plastic jacket is chewed off, two bad things can happen. The conductors can touch each other or the frame and arc, which is a hot electrical spark. Or the inverter sees a ground fault or an arc fault and shuts that part of the system down, which is the equipment doing what it is supposed to do. The inverter page is that shutdown. Resetting the alert without finding the chewed spot just turns the spark back on.

You will usually see it first as a number, not as a fire. One panel, or one group of panels, drops to zero on a clear day while the others keep working. Nesting material hangs out of the gap. Droppings streak the wall under the eaves. With binoculars, from the ground, the cable jacket looks ragged at the edge of the array. Any of those is a call. None of them is a Saturday project on a tile roof.

A module warranty is not going to pay for this. Qcells, as one plain example, excludes damage caused by animals from its limited warranty. Other makers use the same idea, sometimes in different words. Read the page that came with your modules before you argue with the manufacturer. Animal damage is the exclusion. A workmanship warranty from the installer might cover a bad crimp the crew left. It usually does not cover a squirrel that moved in two years later.

The homeowners policy is a second disappointment, and it is not the same as the module warranty. A typical HO-3 policy, the standard homeowners form, says it does not cover damage by birds, vermin, rodents, or insects. The chewed cable is that kind of damage. The part people miss is the next sentence in many of those forms: an ensuing loss that the policy does cover is still covered. If the chewed wire starts a fire, the fire damage to the house can be a claim even though the cable itself is not. Florida policies are not all the HO-3 form. Read yours, and do not file a “squirrel” claim expecting a new harness. The insurance page is the rest of what that policy does and does not do for an array.

A screen is the right tool, in the right order

The product is a critter guard. It is a strip of wire mesh, usually steel with a coating so it does not rust on the first rainy season, clipped around the open edges of the array. It closes the door. It is not a pesticide, and it is not a sheet of plastic bird net. Soft net sags, traps animals, and holds leaves. A rodent can chew it. Steel wire is the version that matches the teeth.

The order is the whole job.

• Look under the array, which means a person who is allowed to be on that roof, not you on a ladder “for a minute.”
• Get any animal out before the gap is closed. Sealing a live animal in is how you get a dead animal, a smell, and a chew from the inside.
• Repair the wires that are already damaged. A licensed electrician, or the company that still honors the work, replaces the chewed leads and checks the connectors. Mesh over a bare conductor hides the fault. It does not fix it.
• Clean out the nest and the droppings. That debris holds moisture against the roof and the metal.
• Then fit the mesh to the whole perimeter, including the corners and any place two rows of panels leave a tunnel. One open end is a door.

Clipping the mesh to the frame, without drilling the module and without new holes in the roof, is the usual method. Drilling the frame can void the module warranty for a different reason than the squirrel. Ask, in writing, that the guard will not be screwed through the panel or the shingles. Do not accept a price that skips the inspection. A screen on top of unknown damage is a cosmetic.

Leave the cavity able to breathe. The mesh stops animals. It should not turn the underside into a closed box. Packed foam, solid flashing across every inch, or a mat of leaves behind the new screen makes the modules run hotter. Heat is already a Central Florida tax on production. The heat page is that tax. A guard that chokes the airflow spends the savings you thought you were protecting.

Contractors advertise a wide range of prices for this, and the range is not a quote. A simple rectangle on a one-story shingle roof is a different afternoon from a cut-up tile roof with three array islands. Get the number for your roof, after someone has looked underneath. If they find chewed copper, that repair is a separate line. Do not let it disappear into the mesh price.

What you can do without a ladder

University of Florida extension is blunt about the road onto the roof. Prune limbs that touch the house. Take palm fronds off if they hang over the roof. Rats and squirrels use those as a highway. A gap of several feet is the point, because a roof rat’s jump is measured in feet, not inches. That pruning does not replace the mesh. It removes the easiest commute.

From the ground, once a month, the same look you already owe the array:

• Nesting material, straw, or a gray rag of insulation sticking out from under the panels.
• Droppings on the wall, the gutters, or the panels at the lower edge.
• A cable that looks frayed where it leaves the array, seen with binoculars.
• On the app, one rectangle at zero, or an arc-fault or ground-fault message, on a day the rest of the array is producing.

Do not set poison on the roof. A bait block above the array is how a poisoned animal dies in the cavity or in the attic, and how bait ends up in the gutter. Do not shoot at the roofline. Do not pull wires to “see if they’re loose.” Those wires can be live in daylight even when the inverter has shut the house side off. The hurricane page makes the same point after a storm. It applies to a squirrel.

If the nest is occupied, a wildlife control company removes the animals and then the solar company, or an electrician, does the wire and the screen. Those are two trades. The person with the traps is not automatically the person who should open a connector.

Ask for it before the array is closed up

The cheap time to do this is while the crew is already on the roof for the original install, after the wiring is finished and before they leave. It is a line on the quote, not a mystery. If the proposal is silent, ask whether the edges will be screened, what the mesh is, and whether the price includes it. A company that says animals are not a Florida problem has not worked here long.

If the system is already up, add the guard when the wires are still intact, not after the first arc-fault email. The permission-to-operate page is the moment you still have the contractor’s attention. Mention the screen before that attention ends. And if a later company offers to “critter-proof” the array by drilling through the modules or smearing sealant over the leads, send them away. The installer guide is how you check the license of whoever you do hire for the repair.

This page is general information, not a pest diagnosis or a reading of your warranty. The chewed wire is an electrical repair. The nest is a wildlife problem. The mesh is what keeps the next one out.