NTR Wood Protection Classes

Complete table of all NTR-wood protection class and related use class and product data

Wood protection classNWPC Quality MarkColour codeShort DescriptionWood SpeciesScopeNWPC protection class general usageUse Class according to EN 335Use Clas DesriptionService conditionsManufacturing technologyPenetration class according to EN 351-1PenetrationPenetration class descriptionRetention requirements
NTR Antr-aWHITEPreservative treated Pine or other soft wood for in ground contact usePine (Pinus spp) and other permeable softwoods according to EN 350 with sapwood that is classified as treatability class 1.The wood protection classes refer only to the protection against biological deterioration. Any other requirements on the treated wood, such as wood quality grading, machining before treatment and moisture content on delivery must be specified separately.Consumer, Construction, Utility poles, Sleepers, Industrial joineryYesUC 4Wood in contact with the ground or fresh water or severely exposed to the weather; or if a wood component is inaccessible or where the consequences of failure will be particularly serious.Exterior stairs, load-bearing wooden structures, balcony and stair railings. Wire posts, piles, sleepers, fence posts, bridgesVacuum pressure impregnationNP5NTR-A PenetrationFull sapwoodAccording to NWPC approval for the wood preservative
NTR A modntr-a_modWHITEChemical modified wood for in ground contact useWood species in accordance with NTR approvalThe wood protection classes refer only to the protection against biological deterioration. Any other requirements on the treated wood, such as wood quality grading, machining before treatment and moisture content on delivery must be specified separately.Consumer, Construction, Industrial joinery, Utility poles, SleepersNoUC 4Wood in contact with the ground or fresh water or severely exposed to the weather; or if a wood component is inaccessible or where the consequences of failure will be particularly serious.Exterior stairs, load-bearing wooden structures, balcony and stair railings. Wire posts, utility poles, piles, sleepers, fence posts, bridgesChemical modificationNP5Full sapwoodAccording to NWPC approval for the wood preservative
NTR A Polentr-a_poleWHITEPreservative treated Pine or other soft wood for poles in ground contact use Pine (Pinus spp) and other permeable softwoods according to EN 350. Permeable softwoods are those whose sapwood is classified in treatability class 1.The wood protection classes refer only to the protection against biological deterioration. Any other requirements on the treated wood, such as wood quality grading, machining before treatment and moisture content on delivery must be specified separately.Utility polesYesUC 4Wood in contact with the ground or fresh water or severely exposed to the weather; or if a wood component is inaccessible or where the consequences of failure will be particularly serious.Wire posts, utility poles, bridgesVacuum pressure impregnationNP5NTR-Pole PenetrationFull sapwoodAccording to NWPC approval for the wood preservative
NTR ABntr-abYELLOWPreservative treated Pine or other soft wood for above ground usePine (Pinus spp) and other permeable softwoods according to EN 350 with sapwood that is classified as treatability class 1.The wood protection classes refer only to the protection against biological deterioration. Any other requirements on the treated wood, such as wood quality grading, machining before treatment and moisture content on delivery must be specified separately.Construction, Consumer, Industrial joineryYesUC 3Wood above ground and either continually exposed to the weather or subject to frequent wetting; where it is relatively easy to replace damaged components and where the consequences of failure will be moderate.Vacuum pressure impregnationNP5NTR-AB PenetrationFull sapwoodAccording to NWPC approval for the wood preservative
NTR AB Modntr-ab_modYELLOWChemical modified wood for above ground contact useWood species in accordance with NTR approvalThe wood protection classes refer only to the protection against biological deterioration. Any other requirements on the treated wood, such as wood quality grading, machining before treatment and moisture content on delivery must be specified separately.Consumer, Construction, Industrial joineryNoUC 3Wood above ground and either continually exposed to the weather or subject to frequent wetting; where it is relatively easy to replace damaged components and where the consequences of failure will be moderate.Chemical modificationNP5Full sapwoodAccording to NWPC approval for the wood preservative
NTR Bntr-bREDPreservative treated Pine or other soft wood for use in window and door joinery, etc.Pine (Pinus spp) and other permeable softwoods according to EN 350 with sapwood that is classified as treatability class 1.The wood protection classes refer only to the protection against biological deterioration. Any other requirements on the treated wood, such as wood quality grading, machining before treatment and moisture content on delivery must be specified separately.Industrial joineryYesUC 3Wood above ground and either continually exposed to the weather or subject to frequent wetting; where it is relatively easy to replace damaged components and where the consequences of failure will be moderate.Vacuum pressure impregnationNP3NTR-B PenetrationMin 6 mm lateral into sapwoodAccording to NWPC approval for the wood preservative
NTR B Modntr-b_modREDChemical modified wood for use in window and door joinery, etc.Wood species in accordance with NTR approvalThe wood protection classes refer only to the protection against biological deterioration. Any other requirements on the treated wood, such as wood quality grading, machining before treatment and moisture content on delivery must be specified separately.Industrial joineryNoUC 3Wood above ground and either continually exposed to the weather or subject to frequent wetting; where it is relatively easy to replace damaged components and where the consequences of failure will be moderate.Chemical modificationNP3Min 6 mm lateral into sapwoodAccording to NWPC approval for the wood preservative
NTR GRANntr-granORANGEPreservative treated spruce for use in some carpentry outdoorsSpruceThe wood protection classes refer only to the protection against biological deterioration. Any other requirements on the treated wood, such as wood quality grading, machining before treatment and moisture content on delivery must be specified separately.Consumer, Construction, Industrial joineryYesUC 3Wood above ground and either continually exposed to the weather or subject to frequent wetting; where it is relatively easy to replace damaged components and where the consequences of failure will be moderate.Vacuum pressure impregnationNP1NTR-B PenetrationNoneAccording to NWPC approval for the wood preservative
NTR GWntr-gwBROWNPreservative treated spruce for use in windowsSpruceThe wood protection classes refer only to the protection against biological deterioration. Any other requirements on the treated wood, such as wood quality grading, machining before treatment and moisture content on delivery must be specified separately.Industrial joineryYesUC 3Wood above ground and either continually exposed to the weather or subject to frequent wetting; where it is relatively easy to replace damaged components and where the consequences of failure will be moderate.Vacuum pressure impregnationNP1NTR-B PenetrationNoneAccording to NWPC approval for the wood preservative
NTR HCntr-hcORANGEPreservative treated hart wood for use in cladding (Hartwood Cladding)EN350-1 Durabillity class 3 or betterThe wood protection classes refer only to the protection against biological deterioration. Any other requirements on the treated wood, such as wood quality grading, machining before treatment and moisture content on delivery must be specified separately.Consumer, Construction, Industrial joineryNoUC 3Wood above ground and either continually exposed to the weather or subject to frequent wetting; where it is relatively easy to replace damaged components and where the consequences of failure will be moderate.Vacuum pressure impregnationNP1NTR-B PenetrationNoneAccording to NWPC approval for the wood preservative
NTR HWntr-hwBROWNPreservative treated hart wood for use in windows (Hartwood Windows)EN350-1 Durabillity class 3 or betterThe wood protection classes refer only to the protection against biological deterioration. Any other requirements on the treated wood, such as wood quality grading, machining before treatment and moisture content on delivery must be specified separately.Industrial joineryNoUC 3Wood above ground and either continually exposed to the weather or subject to frequent wetting; where it is relatively easy to replace damaged components and where the consequences of failure will be moderate.Vacuum pressure impregnationNP1NTR-B PenetrationNoneAccording to NWPC approval for the wood preservative
NTR Mntr-mBLUEPreservative treated Pine or other soft wood for salt water contact Pine (Pinus spp) and other permeable softwoods according to EN 350 with sapwood that is classified as treatability class 1.The wood protection classes refer only to the protection against biological deterioration. Any other requirements on the treated wood, such as wood quality grading, machining before treatment and moisture content on delivery must be specified separately.Consumer, Construction, Utility polesNoUC 5Wood constructions in sea water with salinity > 0,6% and constructions subject to extreme conditions or where there are special durability and strength requirements.Vacuum pressure impregnationNP5NTR-M PenetrationNoneAccording to NWPC approval for the wood preservative
NTR M Modntr-m_modBLUEChemical modified wood for salt water contact Wood species is defined in accordance with NTR approvalThe wood protection classes refer only to the protection against biological deterioration. Any other requirements on the treated wood, such as wood quality grading, machining before treatment and moisture content on delivery must be specified separately.Consumer, Construction, Utility polesNoUC 5Wood constructions in sea water with salinity > 0,6% and constructions subject to extreme conditions or where there are special durability and strength requirements.Chemical modificationNP5NoneAccording to NWPC approval for the wood preservative