I'm making some hypothetical blueprint ideas and started thinking about the various floor joist options. In our neck of the woods, I-Joists are by far most common with floor truss systems becoming more common on only higher end ($$$) homes. I do like them, but they are typically 2.5x the cost of a traditional I-Joist (after delivery fees). I can typically pour a 9' basement cheaper and use regular I-Joists than I can go with an 8' basement and use floor truss systems to make up for the missing height and keep everything above the bottom chord of the floor truss. So it doesn't seem like an economical option.
I was thinking about how people are now tiling directly over their OSB subfloor, or sometimes they will tile over 1/4" underlayment, or something like 1/4" densshield type material. I can only assume this is possible with an L/600 rated floor joist.
One thing I don't like about tiling is trying to meet the deflection ratings with plywood or thicker tileboard. Would it be possible to simply order two different types of I-Joists and mix them, or would you notice the moment you step onto the lesser quality floor joist part of the home?
Example: L/600 I-Joist under the kitchen and dining area that has tile, and then L/360 I-Joists under the rest of the home that is laminate or carpet.