Procrastination is NOT a good thing, as a result we have not only water damaged flooring and subflooring but the kitchen floor is starting aslant. I am figuring on the following to repair the damage I just need to know if I'm headed in the right direction.

1. All the existing damaged flooring material has got to go. That's a given, plus I'm thinking of taking an extra foot around the area to be on the safe side.
2. The joists appear to have suffered some water damage as well, at least 2 of them, so I'm thinking I'll have to laminate joist materials over the damaged ones, jacking them back up and adding stacks or permanent floor jacks as a means to level the area.
3. Only then can I look at reinstalling the subfloor material and flooring.

The issue I have is with #2, should the joist material I use be treated wood or untreated and should it extend the full length of the existing joist or just the area with regards to the damage plus a bit to level up the floor?

Thankfully we have several folk in our parish who are Habitat for Humanity builders who have offered their assistance in helping us get this done so all we will actually be out is the materials, food and drink, plus plenty for tips for these great folks!

Any and all suggestions would be appreciated!!