I can't imagine a good craftsman installing that plank. Or continuing with the next one when the problem surfaced right in front of his eyes. Stop the install. Have that replaced. Then allow them to continue.

Thank you. It is already installed everywhere, but not sanded or stained yet. I imagine it’s okay to replace just that plank? They’re so tight/ I worry it wouldn’t work.

Bad millwork, your finisher can sand it flat. If, you want bad millwork sorted out. pay the installer the time to do it. They will need to open every bundle and inspect every single board, with a visual , then measure the width and thickness. You will need a lot of space to do the inspection.

Floor installation is production work charged by the square foot, not hourly. If, it visibly stands out it can be caught and removed. Often, it is not caught until the next row is installed. Purchasing better quality flooring helps but does not alleviate bad millwork that slips through. Filling with wood putty is a common industry practice. Everybody does it. Really bad boards are swapped out.

If, you want high end craftsmanship, hire a craftsman and pay them hourly.

That plank was improperly milled by a planer or machine sander. You don't need a high-priced cabinetmaker to recognize a defective plank. And 'sanding' it down has to create a dip; Thats obvious from visual dimension differences. I'd question this guys abikity to remove the plank and replace it. Bring in a higher priced better qualified alternative floor pro for his opinion and estimate. Have him complete the remainder of your floor, if you feel that's the way forward. I wouldn't sand this out.

Some people commenting obviously aren't installers, so take that into account.

It's unfortunate that piece was installed, but now that it is, it would be best to sand it along with the entirety of the floor rather than losing parts of the t&g.

Show this to the installer. Much less time and expense than sanding the whole floor.

Thank you everyone for the helpful responses. This is a reputable hardwood floor company who installed in our previous home, and I’m hopeful he’s right that sanding it down will work. But, he seems like the kind of guy to fix it until it’s done right. So we will see!

Hardwood has only a specific dimension you can sand before you hit the tongue. That small amount of wood is all you're allowed for refinishing. You're going to lose a good chunk of your floor. The guys this company has now are likely not the guys working when you had the floors at your last house installed. They are slacks.

Most millwork is within +/- 1/64". If, you look around at the other boards. There are a lot of over and underwood throughout, that needs to be sanded flat, about 1/32" total. That planer mishap is about 1/32. It will sand out flat with no issues. I wouldn't worry.

On average a refinisher will remove 1/32" each time the wood floor is sanded. You can remove a maximum of 5/32 out of 1/4". Which no chance will it happen in one sanding. So, that's 5 sanding through it's life cycle. Which no one lives in the house long enough to see. You have brand new floors, nothing to worry about.

Looks great!