Copper Naphthenates

Copper Care Wood Preservatives, Inc. can supply your company with the copper naphthenate solution you need. Cu-Nap Concentrate and ready-to-use Tenino Copper Naphthenate® are available in a wide variety of packaging options: two-hundred- and seventy-gallon totes down to pint bottles. Pints of Tenino Copper Naphthenate® are favored by utility linemen, while single gallon containers of ready-to-use Tenino Copper Naphthenate® are stocked by many fine retailers and available online at 55 Gallon drums and 260 gallon DOT totes of Cu-Nap Concentrate are economical solutions for many bulk fence post treaters - Copper Care Wood Preservatives' offers Tenino Copper Naphthenate® and Cu-Nap Concentrate in packaging that works for you.

Performance Studied Proven

In a major 50+ year study by the USDA Forest Product Laboratories, wood treated with copper naphthenate demonstrated similar performance to that of creosote treated woods.

Fifty Year USDA Forest Products Laboratory Study
Results of a fifty-year USDA Forest Product Laboratory study demonstrates Cu-Nap Concentrate has similar performance to Creosote and Pentachlorophenol. USDA Forest Products Laboratory Study

Labeled for General Use

Copper Naphthenate is an oil-borne wood preservative classified as a General Use pesticide by the Environmental Protection Agency (EPA) under the Federal Insecticide, Fungicide and Rodenticide Act (FIFRA). Tenino Copper Naphthenate®, and Cu-Nap Concentrate are EPA registered “general use” preservatives and have been standardized for use by the American Wood Protection Association (AWPA). Copper naphthenates may be used in pressure treatment for utility poles, bridge timbers and railroad crossties. Copper naphthenate is the only pesticide product not Labeled Restricted Use in this market. Copper naphthenate has a low mammalian toxicity profile.

Our Copper Naphthenates are EPA Registered Pesticides. Always read and follow all Label Directions. EPA Labels carry the full force of Federal Law

Fence posts treated with Cu-Nap Concentrate copper naphthenate.

Copper Care Wood Preservatives' Cu-Nap Concentrate (8% Cu as metal) is a liquid Copper Naphthenate wood preservative that can be diluted with diesel or mineral spirits. It is widely used for pressure treatment of ground contact lumber and as a dip treatment for fence posts using a 24-hour soak. Cu-Nap Concentrate is labeled for the treatment of posts, poles, lumber, siding, boxes, roof shakes and shingles, fence pickets, landscape timbers, cellulose textiles, and cordage. Apply by brush, dip, or pressure treatment. Cu-Nap Concentrate is a cost-effective solution for large volume, commercial users. For dilution and other detailed information, refer to the product label, the product flyer, or call us.

Tenino Copper Naphthenate on treated wood end-cuts pressure.

Tenino Copper Naphthenate® contains 2% metallic copper (by volume) and may be used to satisfy AWPA Standard M-4 field treatment of pressure treated wood.

Copper Naphthenate preservatives containing a minimum of 2.0% copper metal are recommended for material originally treated with copper naphthenate, pentachlorophenol, creosote, creosote solution or waterborne preservatives.

American Wood Protection Association

AWPA M4 Standard §7 field treatment of wood


Demonstrated Efficacy

USDA Forest Service Forest Products Laboratory studies document long-term performance. American Wood Protection Association (AWPA) Standards ensure peer review and qualify intended applications.

Protects Against

Subterranean Termites

Carpenter Ants

Decay Fungi

Drywood Termites

Wood Destroying Beetles

Powder Post Beetles

Formosa Subterranean Termite Protection
Copper Naphthenate protects against insects including Formosa Subterranean Termites Lightbox

Copper is both repellent and toxic to termites. The University of Hawaii has found Copper Naphthenate in wood at loadings of 1.5 lbs. per cubic foot is resistant to Formosan Termite attack and degradation. Copper Naphthenate will successfully protect against termites only if minimum loadings and sufficient penetration are achieved. Copper Naphthenate is best used to supplement pressure-treated preservative wood protection in aggressive hazard class environments envisioned in AWPA Use Category 4, 4B,4C.

Non-Corrosive to Hardware and Fasteners

 Multiple studies demonstrate no excessive corrosion of hardware and fasteners due to contact with the preservative.

Copper Naphthenate Is Time Tested

Copper Naphthenate has been used as a wood preservative for over one hundred years with many applications for use, including field boxes, benches, flats, fence posts, water tanks, canvas, burlap, ropes, nets, greenhouses, utility poles, crossarms, and wooden structures in ground contact and above ground contact.

Reveals Natural Wood Grain

Bright green color of wood freshly treated with copper naphthenate will become brown in outdoor exposure.


Durable Packaging

Black Nylon fortified HDPE one-gallon jugs and clear PET pints provide excellent resistance to aromatic hydrocarbon degradation. Our containers and copper naphthenate products have a shelf-life rating of five years. A unique induction sealing process utilizes 18-micron copper foil eliminating galvanic degradation.

Waste Disposal

Copper Naphthenate treated wood waste is neither a listed nor a characteristic hazardous waste according to the current EPA regulations under the Resources Conservation and Recovery Act (RCRA). It may be disposed of in landfills in accordance with federal, state, and local regulations.

100% Domestic

The primary constituents of the treating solution are derived and/or manufactured from domestic sources by US owned companies.

Which Copper Naphthenate is right for your needs?

Ready-to-use Tenino Copper Naphthenate® is suitable for most consumer applications.

Cu-Nap Concentrate must be diluted in accordance with label directions prior to use and is best suited for high volume applications (greater than 260 gallons per year) by experienced applicators.

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