Design and Engineering for Wood Poles
Preservative-treated wood utility poles are essential to the North American electricity distribution system. Each pole serves as an engineered structure, supporting considerable weight from power lines, transformers, co-axial cable, fiber optic cable and other loads.
Standards that define the quality, dimensions and basic engineering data for preserved wood poles were first written in the early 1900s. Design values for wood poles have been refined over the decades through testing and an extensive record of in-place performance under rigorous conditions.
Review and download the following engineering reference materials and design tools for your computer, smartphone and tablet. Please note the American National Standards Institute (ANSI) maintains the basic standards for wood poles and crossarms, which must be purchased directly from ANSI.
Engineering & Design
National Wood Pole Standards Video Series
Three-part video presentation on wood pole standards in the NESC, reviewing the standards process, strengths, loads, groundline stresses, transverse loads and other technical data. Presented by ANSI O5 Committee Chairman Nelson Bingel.
Video, 04/20
ANSI O5.1-2022 – Wood Poles, Specifications and Dimensions
FOR PURCHASE ONLY. The minimum specifications for the quality and dimensions of preservative-treated wood poles that are to be used as single-pole utility structures.
Buy for $60 at ANSI eStandards Store
ANSI O5.3-2021 – Solid Sawn Wood Crossarms and Braces
Product technical sheet reviewing checks and splits in timbers, beams,posts and other sawn lumber, why they occur and how they typically have little impact on the structural or servicability of preserved wood products.
1 page, 06/23
Technical Bulletin – Sustainable Wood Pole Design for Overhead Systems
Review alternatives to sustainably improve overhead system resiliency without increasing pole sizes to classes that are more difficult and expensive to source. Includes examples for shortening spans between poles to utilize more sustainable and readily available wood pole sizes.
12 pages, 02/20
Technical Bulletin – Unique Overload Capacity of Wood Poles
Reviews how natural variations and recognition of such variations in the National Electric Safety Code allow wood poles to have a much greater overload capacity in extreme weather events compared to poles made from alternative materials.
8 pages, 10/19
Technical Bulletin – Wood Pole Design Considerations
Explores the basics of wood pole design, including the structural criteria that must be considered in determining the proper wood pole for specified loading, wind, ice and other conditions under the National Electric Safety Code.
16 pages, 07/19
Technical Bulletin – Wood Utility Pole Design Values in the NESC
Provides the fiber strength and Modulus of Elasticity (MOE) design values for all species used for wood poles in the U.S. The values are listed in the 2022 edition of ANSI O5.1 Wood Pole, Specifications and Dimensions.
4 pages, 08/24
Technical Bulletin – “Wood Equivalent” Poles and the NESC
Discussion of issues in marketing thin walled steel poles, prestressed concrete poles, and fiber-reinforced polymer poles as “wood equivalent.” Includes details on how the NESC applies different strength and load factors for each material, which means there can be no true “wood equivalent” poles.
8 pages, 05/17
ANSI Dimensions for Wood Poles
Excel spreadsheet that calculates the minimum circumference of a wood pole 6 ft. from the butt, based on selection of species, class and length. Requires Excel 2007 or higher.
ZIP file (151KB), 03/14
Get this tool for your smartphone or tablet!
Download the free Wood Pole Guide app.
Excel spreadsheet that calculates range of pole weights for shipping based on selection of species, class and length. Includes estimators for single poles and multiple pole selections. Requires Excel 2007 or higher.
ZIP file (115KB), 03/14
Get this tool for your smartphone or tablet!
Download the free Wood Pole Guide app.
Verification of ANSI O5.1 Southern Pine Wood Pole Strength Values
A 2014 research paper on research verifying published ANSI strength values for Southern Pine utility poles, confirming that poles with higher summerwood percentages are as strong as slower growing trees. Published in the 2014 AWPA Annual Meeting Proceedings.
12 pages, 06/15
Juvenile Wood Concerns in Southern Yellow Pine Poles
Statement addressing juvenile wood concerns and the impact on strength of treated Southern Yellow Pine poles.
1 page, 04/04