PWT I-Joists

I-Joist are strong, lightweight, “I” shaped engineered wood structural members that meet demanding performance standards. I-Joist are comprised of top and bottom flanges, which resist bending, united with webs, which provide outstanding shear resistance. The flange material is typically laminated veneer lumber (LVL) or solid-sawn lumber, and the web is made with plywood or OSB. The robust combination of structural characteristics results in a versatile, economical framing member that is easy to install in residential and light commercial projects. https://www.apawood.org/i-joist

I-Joist are used extensively in residential floor and roof framing. They are ideal for long spans, including continuous spans over intermediate supports. Because I-Joist are straight and true, it’s easier for builders to avoid crowning and maintain a level framing surface. In addition, wood I-Joist are typically stocked and readily available in depths that meet the needs of residential framing. (https://www.apawood.org/i-joist)

PWT I-Joist are a balanced product and do not have a top or bottom like an unbalanced glulam. However, the web does have pre-punched knock-outs that are closer to one flange. The knock-outs are easier for electricians to use when located near the bottom of the installed joist.

Don’t panic! There is technical staff available to help you. Contact the supplier you purchased the product from. They will help you through the process. Expect to fill out a damage report form, take measurements, and send pictures. They will run a calculation and let you know how to proceed.

Engineered Wood Products (EWP), including prefabricated wood I-joists and LVL, have been successfully used in dry service conditions, including exterior applications that are protected from precipitation, for several decades. Except for PWT Treated LVL, PWT products are not intended to be installed in applications where permanent wet-use conditions exist. Dry service conditions for EWP are defined similarly in the United States and Canadian building codes. In the U.S., the National Design Specification (NDS) of Wood Construction defines dry service conditions in sections 7.1.4 (wood I-joists) and 8.1.4 (structural composite lumber) as “...where the moisture content of sawn lumber in service is less than 16%, as in most covered structures.”. In Canada, CSA O86 defines the dry service condition as “...a climatic condition in which the average equilibrium moisture content of wood is 15% or less on average over a year without exceeding 19%.” For more information refer to the Wood-I-Joist Manufacturers Association (WIJMA) document: Use of non-preservative treated products in protected non-conditions applications.

Code Reports are used by building officials and design professionals to determine a product’s compliance with building codes and standards. The report also includes a description of product use, design values, and how to identify the product. Code Reports are issued by entities that have reviewed test reports and audit a manufacturer’s quality management system.

I-Joist Floor Assemblies

I-Joist Code Requirements

Installation Guides

Web Hole Specifications