I was called out to investigate 14 I-joists in the basement of a new house under construction. The owner complained to the builder these joists were darker with black and white spots. I arrived and it was obvious these joist were stored outside for an extended period of time bundled for shipment like in the photo below:
The following photos show these joist already in place;
The date stamp on the I-joist were a year older then the other I-Joists installed:
Using a screwdriver I demonstrated to the home owner and the contractor on the good I-Joists I could not poke the screwdriver through the web with considerable force. Then I proceeded to poke holes in the darken joists as the contractor’s face turned white. He told the homeowner it was only a little mold and he sprayed it with a fungicide. Turns out significant dry rot fungus had developed where the flanges were touching the web when bundled. (see first photo above)
Waiting until the I-Joist supplier and contractor decide what they want to do. Meanwhile I am working on a possible repair.