At night, every bug in America flies up to my exterior lights and dies attached to my siding. There are constantly dead insects around my exterior light fixtures.

Is there any reason not to spray some bug repellent (DEET for example) compound on the siding and the light fixture to keep the bugs off these surfaces?

The siding is wood siding.

Note Previously the question asked specifically about using permethrin which is not a repellent.

  • Possible staining or paint stripping. Liquids near/on electric fixtures is never recommended, unless the fixture is sealed/made for wet conditions.
    – crip659
    May 17, 2023 at 22:46
  • It might be easier to change the lights to the bug repellent type(yellow colour), instead of light colours that attract bugs. Not like you use those lights for reading/watching TV, just to see.
    – crip659
    May 17, 2023 at 23:21
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    Are you an entomologist? If not, I would not presume that since DEET is sold as a mosquito "and certain other biting insects" repellent, therefore it works on all 6-legged invertebrates. That would be like presuming that since cats hate peppermint, that works on all mammals. May 17, 2023 at 23:47
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    You could aways...turn the lights off.
    – Ecnerwal
    May 18, 2023 at 13:20
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    See treehugger.com/… for (one example of) reasons other than it being illegal that spraying DEET on your house is unlikely to "repel" insects. That's not actually what it does, despite it being sold as "repellent"
    – Ecnerwal
    May 18, 2023 at 13:31

3 Answers 3


Certified pesticide applicator here.

Not legally.

All herbicides and insecticides have a warning label that says

"It is a violation of Federal law to use this product inconsistent with its labeling".

enter image description here

So your project would require you to find a product which is certified and labeled for the purpose of applying to walls.

While you're at it, you might also identify a pesticide which is certified and labeled for the species of insect you are trying to repel. DEET is for biting insects such as mosquitoes, and the label says so. E.G.

enter image description here

Aside from the fact that it probably won't work on those herbivore bugs, we're back to the "inconsistent with its labeling" problem, where the product is not listed for that pest.

This prohibition on "off-label use" occurs with all pesticides and many other consumer products with downsides, such as most chemicals.

  • Thanks for the info. Is there any such product to repel bugs from surfaces? I'm kinda surprised here. We're talking a fairly localized application, not applied to skin.
    – User7391
    May 18, 2023 at 1:11

Based on a quick read about Permethrin on Wikipedia, this basically kills bugs. It does not repel bugs.

As a personal protective measure, permethrin is applied to clothing. It is a cloth impregnant, notably in mosquito nets and field wear. While permethrin may be marketed as an insect repellent, it does not prevent insects from landing. Instead it works by incapacitating or killing insects before they can bite.

Emphasis added. This really won't solve your problem. Plus excessive use of insecticides just for convenience and aesthetics really doesn't make sense - the bugs don't hurt the lights.

Look for something that can help repel the insects, ideally without killing them. I am very much in favor of killing insects in more critical areas (e.g., inside a house) but killing them outside doesn't make sense to me unless there is some real use - e.g., to protect a garden from being eaten by insects or to get rid of mosquitos or other dangerous pests.

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    DEET is much more likely to be effective as a repellent. That's the good news. The bad news: 1 (from Wikipedia): DEET is an effective solvent, and may dissolve some watch crystals, plastics, rayon, spandex, other synthetic fabrics, and painted or varnished surfaces including nail polish. Which means it may affect your siding. May 17, 2023 at 23:07
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    2 Bigger problem: It looks like it typically lasts 12 hours or so. Which would mean respraying every day to have much effect. May 17, 2023 at 23:07
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    But all this is based on use of DEET in its usual on-label manner, as personal on-skin repellent for humans venturing outdoors. May 17, 2023 at 23:48
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    A couple of real examples of DEET attacking plastics: The (presumably polyurethane) coating on the inside of a waterproof jacket I had. Even after the repellent had apparently dried, it destroyed the coating on the insides of the sleeves where my bare arms touched the fabric (this was on a visit to Costa Rica, so quite warm even when it rained). Also the coating on the grip of one of my DSLR cameras was softened and wore away. Wood siding is presumably treated - I'd expect DEET to damage most wood finishing products.
    – Chris H
    May 18, 2023 at 10:12
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    DEET is (IIRC) also not actually a repellent, so much as a "prevent the bug from smelling tasty blood-bag-animal" - so an anti-attractant by smell - expect ZERO effect for attraction to light - (and if someone's kid needs a science project, well, here you go!)
    – Ecnerwal
    May 18, 2023 at 13:16

Use blue light fly trap that will just fry them. No harm to you or the environment.

Some study show :General exposure to DEET may also cause gastrointestinal issues or side effects including disorientation, shaking, vomiting, tremors and seizures. ( 11) 6. Environmental Impact The U.S. Environmental Protection Agency says DEET may be slightly toxic to birds, fish and aquatic invertebrates.

That is why not use the chemical spray.

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