The problem with this is that the hardwood floor in the rest of the house runs perpendicular to the original subfloor, which is parallel to the addition subfloor, and parallel to the transition between the two subfloors. If we ran the new hardwood in the kitchen parallel to the hardwood in the rest of the house, Mike said that the uneven subfloor in the addition would cause a "hump" in the floor that the new boards would separate along, and we'd have a gap open up in the floor over time right where the addition meets the original house. This wasn't a problem on the old floor because there was about three layers of plywood spanning the gap, with the linoleum on top covering up all the sins. If we run the new hardwood perpendicular to the rest of the hardwood in the house, it would span the gap, even out the hump, and have the additional bonus of spreading the weight of our new kitchen island more evenly across the joists in the basement ceiling.
So we have to make some kind of transition between the old and new hardwood floors, since they're running perpendicular to each other. This was already an issue anyway because the kitchen hardwood is going to be all sealed up and glossy, so it will have a slightly different sheen than the adjacent old floor in the dining room. The solution was to put in a wide transition strip in the kitchen / dining room doorway, with strips of mahogany, to visually break things up between the old and new floors. In the image below you can see the transition strips installed, with a tiny glimpse of the old dining room floor peeking out from under its protective cover. After the new floor is finished it should bring out more of the rich colors of the oak and mahogany.
The kitchen is starting to look fabulous with the new floor!
I missed talking to anyone on the job today when I got home from work, but my guess is that those two darker patches on the floor are where they spread some extra poly underneath where the dishwasher and refrigerator are going to go, before the cabinet boxes come in a week from now.
Another small conundrum came up when the linoleum was ripped out of the landing next to the back door. The top tread of the basement stairs was under that linoleum, and it's this weird red-painted board. I think it's made out of soft pine based on the grain showing through the paint and the character of the mashed-up front of the stair tread.
I really don't want to mess with the basement stairs which are currently covered in an old gray carpet, and I'd like to leave them that way, thank you. I'm pretty sure that the carpet isn't attached to this tread, and this board is too mashed up to keep. I think this weekend curiosity will get the better of me, and I'll get out the pry bar and take it off so that we can think fresh about the transition from the back door area (in the scope of the project) to the basement stairs (out of scope).