My entire downstairs is oak flooring. There is no stain on the floor just a ploy finish. My dining and formal living room floors are in great shape. I would like to refinish the rest of the floors without touching my dining and formal living rooms. However, the flooring downstairs runs seamlessly without any break or transition. Can I blend a new finish with the old without putting some sort of transition inlay between the area I want finished and the area I want to leave as is?

The refinished area is going to look lighter, cleaner and brighter than the existing area. However, if you would cut-in a turn board between those areas, you would be able (professional must do it) to connect it nicely. I did it many times, it works well but not perfect.

Roman K.

I'd agree. A transition strip between the rooms would work the best, and you can always throw it a piece of a different species in there for a change of pace depending on what colors you like ( walnut, Brazilian cherry, etc )

Otherwise you are going to want to tint your first coat of poly and maybe the second with a clear poly coat on top, but if you aren't careful, you'll have an ugly floor with blotches of color or streaks, etc.