Good morning all. First time poster - this is a great forum and only wish I had stumbled upon it a long time ago.

House had wood floors throughout first floor with the exception of the kitchen. First floor is basically 4 rooms, and walking in the front door you have the dining room front left, formal living room front right, den is back right, and kitchen back left. I set out to put wood floor in the kitchen, tying it in with the rest of the house. Started at the door between the dining room and kitchen, and worked out to the large opening between kitchen and den, which is where the lacing started.

When I started at the dining room door, the profiles of the new and existing boards matched very close, with the new boards being only slightly thicker. However, when I got to the opening at the den and started lacing in boards, there was/is a more significant difference in profiles - about a penny or nickel thickness difference. Despite this potential issue I felt very compelled to finish the floor since we live in the house.

At this point I'm very likely to have a pro come in and sand/finish, but will there an issue with the difference in profiles? What if any would be the additional sanding steps to deal with this? I want to be able to make sure that whoever comes in to sand/finish is capable. Pictures attached - glad to take more if needed. Thanks in advance.

Photos:
https://drive.google.com/drive/folders/ ... sp=sharing

With a big difference in height like this it takes lots of energy to get the area smooth. I think the best way to get the floor flat is to use an edger with 40 or 50 grit paper where sanding the area where the new flooring meets the older flooring. After getting the heights close the big machine should be used diagonally
with 40 or 50 grit to get the area flat, then go with the grain to smooth the diagonal scratches.
It takes checking as the work is progressing to get the best results. Sometimes I use a chalk mark every couple of feet across the boards so I don;\'t need to stop and check with refracted light reflected off the floor surface.