What is eating my house in Mount Pleasant?

Formosan vs Eastern subterranean termites

Both are subterranean species that build colonies in the soil and tunnel up into wood. Formosan termites (Coptotermes formosanus) are far more destructive — a mature Formosan colony can number in the millions versus hundreds of thousands for Eastern subterranean, and Formosan colonies forage faster and cause more structural damage in less time. Both species build mud tubes as protected pathways from soil to wood. If you see pencil-width mud tubes on your foundation, sill plates, or pier blocks, termites are the likely cause.

Swarmers (winged reproductives) help with ID. Formosan swarmers are caramel-colored and swarm at dusk in May and June, attracted to lights. Eastern subterranean swarmers are darker and swarm during the day in late winter through spring. Finding wings or swarmers near windows or light fixtures during these windows is a strong signal that a colony is established nearby.

Carpenter ants

Carpenter ants do not eat wood — they excavate smooth galleries in wood that is already softened by moisture. If carpenter ants are active in your structure, they are almost always a secondary indicator of a moisture problem: a leaking roof, a plumbing slow drip, or condensation accumulation in an insufficiently ventilated crawl space. The frass they produce is clean and fibrous, like coarse sawdust mixed with insect parts, deposited in small piles beneath gallery openings. Control requires locating and correcting the moisture source, not only treating the ants.

Moisture problems that draw carpenter ants aren't unique to Mount Pleasant. The licensed pros we connect you with also handle this in West Ashley, where lots near Church Creek and Rantowles Creek hold groundwater close to the surface, and out toward Johns Island, where tidal marsh along Bohicket Creek keeps sill plates and porch posts damp well past a normal dry spell. Any structure sitting that close to standing or tidal water is a candidate for the same soft, moisture-damaged wood carpenter ants prefer to hollow out.

Carpenter bees

Carpenter bees bore near-perfect half-inch round entry holes into unpainted or weathered softwood — fascia boards, roof overhangs, deck rails, siding. A fresh hole will have a small pile of sawdust below it and, if the female is actively excavating, yellow pollen staining around the entry. Structural damage from a single season is usually limited but cumulative over years; woodpeckers that discover carpenter bee larvae will dramatically expand the damage by excavating the wood to reach them. Painting exposed wood removes the preferred substrate.

Wood decay fungi

Lowcountry humidity, soil-to-wood contact in older crawl spaces, and persistent roof or plumbing leaks create conditions where wood decay fungi establish without any insect involvement. Decayed wood is soft, spongy, or crumbling, often with a musty smell. It does not produce mud tubes (termites) or clean round holes (carpenter bees) or fibrous frass (carpenter ants). A CL-100 inspection reports wood decay alongside wood-destroying insects because lenders treat it as a structural concern regardless of cause.