NatureWood® treated wood products can be used for interior and exterior uses. Exterior uses include above ground, ground contact, and fresh water contact.
End Use Classifications for Naturewood® Pressure Treated Wood Products
General Use - Above Ground
Examples - decking, railings, and balusters
Ground Contact and Fresh Water Contact
Examples - deck posts, fence posts, joists, beams, ledgers, and sills
Ground Contact - Critical Structural Members
Examples - building poles, permanent wood foundations, and salt water splash zones
IMPORTANT: Treated Wood End Use Information
Ground Contact (UC4A) treated wood should be used in the following end use applications:
Ground Level Decks and Walkways
Treated wood when installed less than 6” above the ground.
When treated wood is used in an application that does not permit air circulation or water drainage underneath the structure.
When treated wood is used in an application where vegetation, leaf litter, or other debris will build up and remain in contact with the treated wood product.
Decks and Fresh Water Docks
When treated wood is used in an above ground application where the treated wood component would be considered difficult to maintain, repair or replace and that component is critical to the performance and safety of the structure. This standard change will affect joists and beams used in above ground decks and fresh water docks, including floating docks.
When treated wood is wetted on a frequent or recurring basis such as wind and wave action (such as fresh water docks and walkways) or watering systems, swimming pools and hot tubs.
Export Products - Exterior Use
When treated wood is used in tropical climates.
AWPA U1 Standard and 2015 International Residential Code (IRC)
The American Wood Protection Association (AWPA) has changed the U1 standards for treated wood used in residential, agricultural and commercial applications. The AWPA Book of Standards states, “Standard U1 is the primary standard for specifiers, such as architects and engineers, but also for end users and building code officials. This Standard contains the information needed by specifiers in order to select a product that best suits their needs.”
The residential code (IRC) states that wood that is preservative-treated must be in accordance with the AWPA U1 Standard.
One of the new revisions to the AWPA U1 Standard will change deck and fresh water dock joists and beams to Ground Contact, because those components are typically considered difficult to maintain, repair or replace and are critical to the performance and safety of the structure.
Treated Wood End Use Guide
Above Ground
1
High Level Deck Boards
2
Railings & Accessories
3
Fence Boards and Rails
4
Trellis
5
Lattice
Ground Contact
6
Ground Level Deck
7
Stair Stringers
8
Ledger Boards*
9
Post Supporters
10
Joists*
11
Beams*
12
Planter Boxes
13
Fence Posts
14
Retaining Walls
15
Playset Structures
16
Ground Level Walkway
17
Raised Garden Bed
18
Fresh Water Bulkhead
19
Fresh Water Dock
20
Fresh Water Dock Posts
21
Floating Dock (Decking, Joists, Beams)
When treated wood is used in an above ground application where the treated wood component would be considered difficult to maintain, repair or replace and that the component is critical to the performance and safety of the structure.
New AWPA Standards for Treated Wood
Effective July 2016, the American Wood Protection Association (AWPA) U1 Standard was revised establishing new guidelines for wood treated to UC4A Ground Contact General Use.