So I found out my entire upstairs has hardwood floors. I pulled up the vents in each room. One room has what appears to be MDF board that is level with a section of the hardwood floor. See
It's very possible as I pull up more of the carpet I will find other areas with sections of MDF. It's likely some of the boards were damaged and they pulled em out to level out the surface before installing carpet over it right? Is it reasonable to think I could cut this MDF out and install new hardwood over it? I will then sand and finish it. It's 100% ok if the new hardwood "patches" don't end up looking the same as the old ones when all said and done.
Edit: New picture attached to show board thickness
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