CuNap treatment of bridge timber gaining traction from IWT-Moldrup

IWT-Moldrup, a 3rd generation company for designing and supplying processes and equipment for industrial impregnation of wood, including CCA, creosote, Copper-Organics as well as industrial wood modification, will now be supplying the worldwide first dedicated Cu-Nap plant as the environmentally friendly but effective future alternative to CCA and creosote.

Copper naphthenate (CuNap), has been used for many years in the United States and represents a well tested and well-documented alternative to both CCA and creosote and an improvement over newer Copper Organics.

IWT-Moldrup will supply the first dedicated CuNap plant worldwide for an American producer of wooden bridges in a few months (

Stina Cecilie Moldrup, marketing manager, explains: ​“The timber to be treated is used for bridge construction where the wood durability is of utmost importance for road safety as well as an excellent environmental profile is required since many bridges pass over water-ways. We expect to see a surge in use of Cu-Nap for heavy construction use such as bridges, foundations for housing, and pilings, as wood is an attractive alternative to steel and concrete not only from a CO2 perspective but also ease and speed of construction all year around and not least due to the cost.”​ Cu-Nap is also a more cost effective alternative to using modified timber like IWT-Moldrup’s own unique sustainable resin treatment concept biobiowood. The Cu-Nap preservative is announced to be available from several preservative suppliers world-wide. The first exclusively designed plant in the US has been developed by IWT-Moldrup, in this case, in close cooperation with one of the market ́s chemical suppliers, Nisus Corporation, who is now the leading manufacturer of Cu-Nap in America. Mr. Moldrup, a more than 49 year veteran in the business, explains: ​”The treatment is a hot process contrary to cold processes using other copper-based products. Cu-Nap is not just a simple mixture of copper with naphthenate in an oil. It is a complex formula, and using simple acid-ingredients is not an option, if the durability is to be assured.”

Main photo: IWT-Moldrup CuNap for bridge timber

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