Preservative-Treated : Use and Specification

Presented by Kris Owen, Consultant Prepared by Western Wood Preservers Institute

Disclaimer: This presentation was developed by a third party and is not funded by WoodWorks or the Board “The Wood Products Council” is This course is registered with a Registered Provider with The AIA CES for continuing American Institute of Architects professional education. As Continuing Education Systems such, it does not include (AIA/CES), Provider #G516. content that may be deemed or construed to be an approval or endorsement by the AIA of any material of Credit(s) earned on completion or any method or of this course will be reported to manner of AIA CES for AIA members. handling, using, distributing, Certificates of Completion for or dealing in any material or both AIA members and non-AIA product. members are available upon ______request. Questions related to specific materials, methods, and services will be addressed at the conclusion of this presentation. Copyright

This presentation is protected by US and International Copyright laws. Reproduction, distribution, display and use of the presentation without written permission from WWPI is prohibited.

© Western Wood Preservers Institute 2018

Western Wood Preservers Institute www.wwpi.org 360-693-9958 Course Description

In applications where wood may be exposed to moisture, insects or fungal organisms, preservative-treated wood can help ensure a building’s durability. In this presentation, participants will learn about the manufacturing process for pressure-treated wood, available products and their differences, and how preserved wood is used in construction. Topics will include types of preservative treatments and the required levels of retention, as dictated by the end-use application, desired service life and exposure conditions. AWPA Use Category standards and ICC-ES Report Evaluations will be reviewed, and current issues concerning treated wood in non-residential and multi-family construction be discussed.

4 Learning Objectives

• Learn how to specify pressure treated wood products using the American Wood Protection Association's Use Category System. • Learn where pressure treated wood is required under the Building Code. • Develop an understanding of the AWPA Use Specification Guide, and a list of resources where they can find more information on pressure treated wood.

5 Western Wood Preservers Institute

• Represents preservative treated wood producers, chemical manufacturers and others serving the industry throughout western North America • Mission Increase awareness of the proper use of treated wood products by providing information to: • Owners • Bldg. Material Dealers • Builders • Code Officials • Architects, Specifiers • Ports and Marinas

6 Wood: The Real Renewable Building Product Treated wood products are sustainable

Inputs Outputs • Seed • Oxygen • Soil • Habitat • Water • Stored Carbon • Sun • Mature Forest • CO 30-80 years of • Wood Products 2 forest management

By the time your treated product has served its life, a new one will be grown and ready to replace it

8 Common uses of preservative treated wood in non-residential buildings • members on foundation or in direct contact with concrete (wood frame over podium) • Wood used in balconies, porches, etc. exposed to weather

9 Durability Wood durability is threatened by: • Carpenter ants • Wood boring beetles • Termites • Decay fungi, rot • Fire

10 Wood destroying insects

Wood Boring Beetles

Carpenter Ants

Formosan Termite

11 Wood destroying insects

Wood Boring Beetles

Carpenter $5 Billion Ants

Formosan Termite

12 Termite infestation probability

Figure R301.2(6) International Residential Code

13 Hidden dangers of decay, rot

14 More moisture, more potential problems

15 Solution • Pressure treat wood with preservatives • Extends service life of wood to decades • Maintains reliable physical, mechanical properties • Readily available, safe to work with, cost effective

16 Treated Wood Standards, Production American Wood Protection Association

• Founded in 1904 • Standards writing organization for the U.S. wood preserving industry • Provides technical forum for industry, research, users • Referenced in all building codes • Updated annually – 2017 edition now available

18 AWPA’s role in the treating industry

• Determines if a preservative is effective and can be listed in the standards • Established how much preservative is needed (retention) depending on exposure, use • Industry seeking to minimize chemical use through lower retentions

19 Who determines if preservatives are safe?

• All wood preservatives must be registered • U.S. Environmental Protection Agency (EPA) • Detailed risk reviews for human health, environmental impacts • Product labels designate in where treated wood can be used in construction

20 Pressure treating process

Dried wood is loaded into retort, or pressure cylinder

21 Pressure treating process

Retort is sealed, vacuum applied to remove air

22 Pressure treating process

Pressure applied to infuse preservatives into wood

23 Pressure treating process

Preservatives drained, returned to storage tanks

24 Pressure treating process

Core samples taken to check for retention, penetration

25 Incising to achieve required penetration

Incisor knives mounted on drums

Lumber drawn through the drums

26 Preservatives: Oil-Type and Waterborne Oil-type Preservatives

• Creosote • Pentachlorophenol • Copper Naphthenate

28 Creosote

• One of the first preservatives used • Railroad ties, utility poles, pilings, docks, guard rail posts, bridge timbers • AWPA approved • Ground contact and fresh/salt water immersion

29 Pentachlorophenol

• In use since 1930s • Utility poles, crossarms, pilings, timbers, bridge decking, guard rails • Est. 80%+ of utility poles treated with penta • AWPA approved • Ground and fresh water contact

30 Copper Naphthenate

• AWPA approved preservative for field treatment • Utility poles, crossarms, posts, bridge timbers, decking • Above ground, ground and fresh water contact • Not listed by EPA as a restricted use pesticide

31 How safe are wood preservatives?

32 Regional product differences Western species • Douglas , Hem-Fir, • WWPI members produce only products listed in the AWPA Standards Southern species • Southern Yellow • SYP production includes products listed in AWPA Standards or ICC Evaluation Service criteria

All treated products inspected by accredited agency

33 Waterborne Preservatives

AWPA approved • ACQ – Alkaline Copper Quat • CCA – Chromated Copper Arsenate • ACZA (Chemonite) – Ammoniacal • SBX – Inorganic Boron Copper Zinc Arsenate • PTI and EL2 – Carbon-based • CA – Copper Azole preservatives • MCA –Micronized Copper Azole

34 ACQ – Alkaline Copper Quat

• , Hem-Fir, Southern Yellow Pine • AWPA, ICC-ES approved • Ground and fresh water contact

35 ACZA – Ammoniacal Copper Zinc Arsenate

• Douglas Fir, Southern Yellow Pine • AWPA approved • Ground, fresh and salt water contact

36 CA – Copper Azole

• Douglas Fir, Hem-Fir, Southern Yellow Pine • AWPA approved • Ground and fresh water contact

37 MCA – Micronized Copper Azole

• Douglas Fir, Hem-Fir, Southern Yellow Pine • AWPA and ICC-ES approved • Above ground, ground and fresh water contact

38 CCA – Chromated Copper Arsenate

• Used since the 1940s • Douglas Fir, Hem-Fir, Southern Yellow Pine • AWPA approved • Ground contact and fresh/salt water immersion

39 CCA – Chromated Copper Arsenate

• Industry voluntarily modified EPA registered uses for CCA • Since 2003, CCA not available for consumer, residential applications • CCA approved for industrial use: , highway construction, utility poles, piling, agriculture • EPA does NOT recommend removal of existing CCA structures

40 SBX – Inorganic Boron

• Douglas Fir, Hem-Fir, Southern Yellow Pine • AWPA approved • AWPA C-31 – “Where its application is continually protected from liquid water.” • Sill plate, interior framing applications

41 PTI – Carbon-based preservative

• Douglas Fir, Hem-Fir, Southern Yellow Pine • AWPA, ICC-ES approved • Above ground use only • Low impact on hardware, coatings

42 EL2 – Carbon-based preservative

• Douglas Fir, Hem-Fir, Southern Yellow Pine • AWPA, ICC-ES approved • Above ground use only • Low impact on hardware, coatings

43 Reference for Preservatives

• PreserveTech: Preservatives • Two-page reference sheet • Covers common waterborne preservatives • Available for download at PreservedWood.org in the Tech Library

44 Care and maintenance

• Waterborne treated products can be painted or stained • Follow manufacturer’s recommendations • Water repellent coating recommended annually

45 Field treating

End cuts for preserved MUST be field treated to meet code

46 International Building Code requirements

“Cut ends, notches and drilled holes of preservative treated wood shall be treated in the field in accordance with AWPA M4”

47 Why field treat?

Properly sealed end cuts prevent decay!

48 Field treatments

• Available field treatment products • Tenino Copper Naphthenate (2% oil based) • QNAP 2 Copper Naphthenate RTU (2% oil based) • Copper-Green Brown Preservative (1% oil based) • Copper-Green Preservative (1% oil based) • Woodlife CopperCoat (1% water based)

Photo courtesy of Poles, Inc.

49 Reference for Field Treating

• PreserveTech: Field Treating • One-page reference sheet • Code requirements, recommended treatments • Available for download at PreservedWood.org in the Tech Library

50 Treated Wood and Building Codes International Building Code reference

• Section 2304.11 Decay and Termite Protection

52 International Building Code reference

• Section 2304.11.2 Wood used above ground, all uses

53 IBC – Wood used above ground

• Section 2304.11.2.1 , girders and subfloor • Wood joists or the bottom of a wood structural floor closer than 18” or wood girders when closer than 12” to exposed ground in crawl spaces or unexcavated areas located within the periphery of the building foundation.

54 IBC – Wood used above ground

• Section 2304.11.2.2 Wood supported by exterior foundation • Wood framing members that rest on concrete or masonry exterior foundation walls & are less than 8’’ from exposed ground.

55 IBC – Wood used above ground

• Section 2304.11.2.3 Exterior walls below grade • Wood furring strips or other wood framing members attached to the interior or exterior masonry or concrete walls below grade.

56 IBC – Wood used above ground

• Section 2304.11.2.4 Sills and sleepers • All foundation plates or sills and sleepers on a concrete or masonry slab, which is in direct contact with earth, and sill which rest on concrete or masonry foundations.

57 IBC – Wood used above ground

• Section 2304.11.2.6 Wood , sheathing • Wood siding, sheathing & framing on the exterior of a building having a clearance less than 6” to the ground.

58 IBC – Wood used above ground

• Section 2304.11.2.7 Posts or columns • Posts or columns supporting permanent structures and supported by a concrete or masonry slab or footing that is in direct contact with the earth.

59 IBC – Wood used above ground

• Section 2304.11.3 Laminated timbers • The portions of glued laminated timbers that form the structural supports of a building and are exposed to weather and not protected from moisture.

60 IBC – Wood in contact with ground, water

• Section 2304.11.4.1 Posts or columns • Posts and columns supporting permanent structures that are embedded in concrete that is in direct contact with the earth, embedded in concrete that is exposed to the weather, or in direct contact with the earth.

61 IBC – Wood in contact with ground, water

• Section 2304.11.4.2 Wood structural members • Wood structural members supporting moisture- permeable floors or roofs that are exposed to weather such as concrete or masonry slabs.

62 IBC – Exposed supporting members

• Section 2304.11.5 Supporting member for permanent appurtenances • In geographical areas where needed, wood members which support buildings, balconies, decks or porches if exposed to weather and without adequate cover protection.

63 IBC – Safety from wood-damaging insects

• Section 2304.11.6 Termite protection • In geographical areas where hazard of termite damage is known to be very heavy, wood floor framing in locations specified in Section 2304.11.2.1 and exposed framing of exterior decks or balconies.

64 IBC – Wood in contact with ground, water

• Section 2304.11.7 Wood used in retaining walls and cribs

65 Reference for Codes

• Preserved Wood and 2015 IBC • Covers current code references for preserved wood in construction • Available for download at PreservedWood.org in the Tech Library

66 Treated Wood Quality Marks, Fasteners Product quality mark

• Section 2303.1.8.1 • “All preservative-treated wood shall bear the quality mark of an inspection agency which has been accredited by the American Lumber Standards Committee and complies with the requirements of the ALSC Treated Wood Program or equivalent.”

68 Product quality mark – required information

Proper exposure condition

AWPA standard

Preservative used

Minimum retention

Trademark of Identification of ALSC agency the treating plant

69 Fasteners with treated wood

• Section 2304.9.5 • Fasteners, including nuts and washers, in contact with preservative-treated wood shall be of hot-dipped zinc- coated galvanized steel, stainless steel, silicon bronze or copper • Exception: Plain carbon steel fasteners in SBX/DOT and zinc borate preservative-treated wood in an interior, dry environment shall be permitted

70 Reference for Fasteners

• PreserveTech: Fasteners • One-page reference sheet • Code requirements, recommendations listed • Available for download at PreservedWood.org in the Tech Library

71 Specifying with the AWPA Use Category System AWPA Use Categories

• Based on end use biodeterioration hazard • Five Use Categories based on exposures, expected performance • Categories range from weather protected (UC1 mild exposure/lowest risk) to salt water marine (UC5 severe exposure/highest risk)

73 Use Category 1 – UC1

• Interior construction • Not in contact with ground or foundations • Protected from weather • Protected from interior sources of water • Insect hazard only

74 Use Category 2 – UC2

• Interior construction • Not in contact with ground or foundations • Protected from weather • Subject to dampness and occasional sources of water • Decay fungi and insect hazard

75 Use Category 3 – UC3

• Above ground, exposed to weather • UC3A: Coated and rapid water runoff • UC3B: Uncoated or poor water runoff • Decay fungi and insect hazard

76 Use Category 4 – UC4

• Ground or fresh water contact, exposed to weather • UC4A: Deck supports • UC4B: Foundation, building poles • Decay fungi and insect hazard

77 Specifying UC3B or UC4A

• AWPA standards revised in 2016 • Addresses above ground uses where wood exposed to ground contact hazards • UC4A for wood components used “above ground but are difficult to maintain, repair or replace and are critical to the performance and safety of the entire system/construction” • Specific conditions listed in standards

78 Use Category reference

• Specification Guide • AWPA Use Category standards, retentions for specific products • Available for download at PreservedWood.org

79 Use Category reference

• Infographic • Approved by AWPA • Additional information on UC3B, UC4A specification • Available for download at PreservedWood.org

80 Treated Wood and the Environment Life Cycle Assessments for treated wood

• Borate-treated lumber compared to galvanized steel • ACQ-treated lumber compared to plastic composite decking • Marine pilings compared to steel, concrete, plastic

82 Life Cycle Assessments for treated wood

• ISO 14044 compliant • Peer reviewed to confirm science, data • Independently published in Journal of Cleaner Production and Marine Environmental Engineering

83 LCA conclusions

• Preserved wood products have Composite of 7 environmental indicators, normalized significantly lower impacts than alternatives • Wood uses less energy, water and fossil fuels with lower environmental impacts

84 Reports available for review

• WWPI website: PreservedWood.org • Treated Wood Council website: www.treated-wood.org

85 Handling and Disposal of Treated Wood Safe use of treated wood

• Precautions for treated wood same as for non- treated wood • Avoid frequent or prolonged exposure to ; dusk mask recommended • Consumer info sheets, SDS available from manufacturers

87 Disposal of treated wood

• Reusing treated wood is preferred option • Do not mulch • Do not burn, unless in commercial or industrial incinerators • Not considered hazardous waste, can be disposed at a landfill

88 Any time. Any where.

• Treated Wood Guide app • Free download available for iOS and Android • Key information needed to understand, properly specify treated wood • Search “Treated Wood Guide” in online stores

www.PreservedWood.org

89 Thank You!

Western Wood Preservers Institute www.wwpinstitute.org 360-693-9958 90 Questions?

This concludes The American Institute of Architects Continuing Education Systems Course

For more information: Kris Owen, Consultant [email protected] Western Wood Preservers Institute PreservedWood.org

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