Treated Lumber Classifications: What You Need to Know - Decks …
2020年7月15日 · For decks and docks of all kinds, many contractors choose UC4B and UC4C for the decking and framing. Experienced contractors know that you need to have lumber that is certified for “ground contact” or higher for humid, harsh, or near water applications.
Preservative Use Categories | Western Wood Preservers Institute
Wood treated to UC4C can be used where there is extremely high potential for deterioration, with considerable exposure to moisture such as in rivers or lakes. UC4B service conditions: Ground contact or fresh water contact, heavy duty, critically important components.
Pressure Treated Wood: Types, Grading Standards & More
2007年7月16日 · Pressure treated wood is lumber impregnated with a variety of preservative chemicals to prevent rot and insect infestation in exterior applications like decks and fences. Several species of wood can be treated, but a regionally available species usually predominates in any particular locale.
The American Wood Protection Association (AWPA) Book of Standards addresses changes in Above Ground (UC3B) and Ground Contact (UC4A) use conditions for treated wood. As part of the standards process, the AWPA standards define situations where pressure preservative treated lumber may be
What is the Best Pressure Treated Wood for Ground Contact?
2021年11月13日 · The best treated lumber levels are UC4A and UC4B since the AWPA designates them for ground contact service conditions. UC4A is typically used to construct fences and decks, making it an ideal treated wood for building a …
For Code Officials - AWPA
You should also look for the appropriate AWPA Use Category for the application, such as UC3B or UC4A. Note that in most cases, wood treated to a higher Use Category may be used for applications in a lower Use Category. For example, sill plates are a UC2 application, but you may use wood treated to UC2 requirements or higher, such as UC3B.
UC4B — Wood and wood based materials used in contact with the ground either in severe environments, such as horticultural sites, in climates with a high potential for deterioration, in critically important components. USE ENVIRONMENT: Severe ground contact or salt water splash. Difficult replacement. Exposed to all weather cycles.
Pressure Treated Lumber Grades, Types, and Uses Explained
The recommended type of treated wood for in-ground use is UC4B and UC4C; UC4B has a higher retention level than lower graded types, and UC4C has even more. Marine Grade Wood treated with water-based preservatives for saltwater immersion has significantly higher retention levels than other types and categories.
Use of Treated Wood in Residential and Light Commercial …
2018年10月3日 · UC4A is the most common Use Category for residential construction and is referred to as General Use which includes products such as fence posts, deck posts, ledger boards, joists, beams and decking. UC4B is defined as Heavy Duty use, and includes products such as permanent wood foundations, timber posts and building poles.
For example, sill plates will be a Use Category 2 (UC2), which is an interior-damp application. A residential deck would carry an exterior-exposed Use Category 3B, whereas a ground contact structural post supporting a building would be either a UC4B or UC4C application.