On a recent inspection I observed and noted the lack of backer blocks on these I-Joists. The builder told the client that because the I-Joists were non bearing walls they required NO backer blocks. Though we are no code enforcement officials, I still think that the backer blocks should be installed. Thoughts anyone?
APA: Backer blocks are used to fill the rectangular space between the outside edge of the I-joist flange and the web of the I-joist. In this respect, a backer block is quite similar to a filler block; however, it is only half as thick. Unlike a filler block, the backer block does not run the full length of the I-joist. It is only as long as it needs to be. The purpose of the backer blocks is to provide a flat, flush surface by which surface- or top-mounted hangers or other structural elements can be attached to I-joists.
Perhaps you’re thinking of squash blocks?
I-Joists are proprietary products. Their detailing is up to the manufacturer.