Why Is a Woodpecker Pecking My House?

Why is a woodpecker pecking my house has several answers, and the holes tell you which one you have. A bird hammering a gutter at dawn and making no hole at all is doing something completely different from one drilling a neat row across your siding, and only one of those two is after something inside the wall. Get the behavior right and the response follows. Get it wrong and you buy a deterrent for a problem you do not have.

What is the bird actually doing?

One of a small number of things, and Iowa State Extension lists them: Woodpeckers drum on house siding for four reasons: to obtain food (insects) within the siding, to build a nest, to establish a male's territory, or just for the heck of it.

The territorial one is the case that alarms people most and damages least. The Internet Center for Wildlife Damage Management defines it: Referred to as "drumming," pecking establishes territories and apparently attracts or signals mates. The bird is not trying to get in. It is trying to be heard, and it chooses surfaces accordingly: Both sexes drum by striking their bills against a hollow or dried branch or other hollow or resonant objects.

That last phrase explains the gutter, the flashing, the chimney cap, and the metal vent. A woodpecker drumming on aluminum has found the loudest instrument in your yard, which is the point of the exercise. It is also why drumming is loud, rhythmic, seasonal, and leaves nothing behind, while feeding and nesting are quieter and leave a hole.

So the first question is which of these you are looking at, well before anything about how to stop it, because the territorial version ends on its own when the season does and the other two carry on.

Woodpecker holes in siding, in a neat row

This is the signature case, and the cause is not the one people assume.

Iowa State: The most common woodpecker damage to houses occurs on houses sided with rough-sawn plywood siding. The pattern is distinctive enough to identify from the ground, and the measurements are specific: The holes are about 1/2 inch apart, 1/2 inch in diameter and extend to the middle layers of the plywood.

What the bird is eating is the part almost nobody guesses: In this situation, the woodpeckers are feeding on the larvae of leafcutter bees that have nested within the siding.

The chain that produces this runs through a construction detail. Routing rough-sawn plywood to give it a grooved, board-and-batten look exposes gaps between the plywood's inner layers. Leafcutter bees, which normally nest in hollow plant stems, find those gaps and provision them with cells. A woodpecker, most often a Downy, locates the larvae by sound and works down the line, one hole per larva. That is why the holes are evenly spaced and in a row: they are a map of where the bees nested.

Does a woodpecker on my house mean I have termites?

Not in the common case, no.

The insect involved in the classic row-of-holes pattern is a solitary bee that was using a gap your siding already had. Iowa State is explicit that the bees are not structural pests: The bees do not tunnel or otherwise weaken the plywood, because they utilize gaps that already existed.

Two things follow. The damage is shallower than it looks, since Damage is confined to the face of the plywood. And spraying is not the answer: To my knowledge, there is no effective chemical control for this problem, with the author adding that the bees are a valuable part of the ecosystem and that treating the plants they forage on would be impractical anyway.

None of that rules out an actual insect problem in an actual wall. It does mean that a row of half-inch holes in grooved plywood has a documented explanation that is not termites, and that reaching for an exterminator first is reaching past the likelier answer.

Are woodpeckers protected by law?

Yes, all of them, and this is the constraint that rules out most of what people are tempted to do.

ICWDM states the status plainly: All species of woodpeckers are classified as migratory non-game birds and are protected by the Federal Migratory Bird Treaty Act. Two species carry more protection still, being listed under the Endangered Species Act.

The two sources here are worth reading together, because they emphasize different halves of the same rule. Iowa State puts it as a flat prohibition: Woodpeckers are protected birds and cannot be legally killed. ICWDM describes the narrow exception that exists: When warranted, woodpeckers other than endangered species can be killed under a depredation permit issued by the Law Enforcement Division of the USDI-Fish and Wildlife Service (USFWS), noting that state authorization may also be required and that sound justification must be present.

For a homeowner with holes in the siding, those two statements point the same direction: not without a federal permit you almost certainly will not be granted. What is unrestricted is scaring the bird: Acts of hazing woodpeckers do not require a permit if the species is not endangered.

This is the same body of law that governs what you may and may not do around birds you feed.

How to stop woodpeckers from pecking house siding

Close the opportunity, deter the bird, or offer it something better. All three are in the published guidance.

Close the gaps, which is the fix aimed at the actual cause. Iowa State's recommendation, offered as the author's judgment rather than as a tested protocol: The best prevention, in my opinion, is to examine plywood siding and plug with caulk any gaps exposed along the routed grooves. No gaps, no bee cells, nothing for a woodpecker to hear.

Materials matter more than anything else long term. ICWDM: Use of appropriate exterior construction materials may be the best long-term solution for preventing woodpecker damage to homes and buildings, and for new construction in wooded areas, contractors should use clapboards or synthetic siding.

Deterrents, in the order the source lists them. Exclusion covers netting, metal barriers, and repairing damage quickly. Frightening covers sound and visual devices, the visual list running to Irri-Tape, Mylar tape, mirrors, and predator models. Two repellent compounds are named, methyl anthranilate and polybutene. On poisons the entry is one sentence: toxicants, None are registered.

And the two options this site is in a position to say something about. ICWDM's habitat-modification list includes using suet as alternative food and nest boxes as alternative cavities. Both are things a feeder-keeper already knows how to do: suet in a cage the bird can work vertically is the standard offering for these species, and a box with the right entrance hole is a cavity that is not your wall. Neither is a guaranteed redirect, and the sources present them as options rather than as solutions.

Timing is the one piece of urgency in the guidance: Damage by woodpeckers should be controlled as soon as it appears.

The part that is better news than it looks

Two findings take the worst case off the table.

The first is that this is common rather than personal. A survey quantified it: A survey by Cornell University done in 2001 and 2002 revealed that 33% of 1,185 houses in Tompkins County, NY had some type of damage by woodpeckers or disturbance related to noise of woodpeckers. A third of the houses in one county.

The second is that the damage tends to be self-limiting, for a reason that follows from the mechanism: Siding that is already damaged is not usually reattacked because the gaps are destroyed and no longer suitable for bee nesting. Once the bird has taken the larvae and wrecked the cavity, the reason to come back is gone with them.

Questions people ask

Why is a woodpecker pecking my house? For one of four reasons per Iowa State Extension: insects in the siding, excavating a nest, establishing territory, or no particular reason. The pattern of the damage separates them.

Why do woodpeckers drum on metal gutters and flashing? Because the sound is the purpose. ICWDM describes drumming as establishing territory and signaling mates, done against hollow or resonant objects, which is exactly what metal is.

Do woodpecker holes mean I have termites? Usually not. The common row-of-holes pattern on grooved plywood comes from woodpeckers taking leafcutter bee larvae out of gaps in the plywood layers, and those bees do not tunnel into or weaken the wood.

Are woodpeckers protected by law? Yes. All species are protected under the federal Migratory Bird Treaty Act. Scaring them off requires no permit; killing one requires a federal depredation permit and, often, state approval.

How do I stop woodpeckers from pecking my siding? Caulk the exposed grooves so the bees cannot nest there, use netting or barriers on the damaged area, and consider visual or sound deterrents. On new construction in wooded areas, ICWDM points at clapboards or synthetic siding instead of grooved plywood.

Will it come back next year? Often not to the same spot. Iowa State notes that damaged siding is not usually reattacked, because the gaps that held the bee cells are gone.

Why is a woodpecker pecking my house: the short version

Read the damage before buying anything. Loud rhythmic hammering on metal that leaves no hole is territorial drumming, it is seasonal, and it will stop. A neat row of half-inch holes across grooved plywood is a bird eating leafcutter bee larvae out of gaps the siding was built with, which is a construction detail rather than an infestation, and the fix is a caulk gun rather than an exterminator.

The bird itself is off the table either way, protected by federal law, which leaves closing the gaps, covering the spot, scaring it off, or offering it a suet feeder and a box instead. And the same woodpecker that is a problem on the wall is the one most people are trying to attract to the yard, which is worth remembering before the situation feels like a war.

This article contains no affiliate links. Siding repair methods, replacement costs, and homeowners insurance are outside its scope and outside the sources used here: those are questions for a contractor and an insurer, not for a bird site. Everything above is attributed to Iowa State University Extension and Outreach or to the Internet Center for Wildlife Damage Management.