Hi there...need help blocking these joists (see pic below)...obviously the air ducts are going to cause an issue. How to work around this?

Floor needs to be braced for this add-on sun room (9x7 ft). Hardwoods are going down on this entire level, and the joists here run in the opposite direction as the rest of the house. Would like to block joists in order to run hardwoods in this room the same way as the rest of the house.

Thoughts? How tough a job are we talking? Thank you so much!!

(see pic below)

Cut you some blocks to fit and just skip the two that have the ductwork. My real concern is that the area below is going to be "open" to the outside air. You may get some movement over that section due to the larger swings in moisture content that will be allowed by this type construction.

Is your subfloor super flat?

I did the entire 2nd story of my house in solid red oak parallel to the joist, it was against my better judgment but aesthetically just worked way better. The biggest problem i had was the subfloor diving / waving between the joist. In some spots the subfloor dropped as much as 3/4". I ended up using thin cardboard and a bunch of old cedar shake roofing that I had to build up the low spots.

All in all it came out well but we'll see what time has to say about it.

Best of luck to you.