Hi there. I would like your professional thoughts on the red oak mismatch and blistering at the joints.

In October 2015 I hired a licensed hardwood floor contractor to lace new material into our existing 1.5" red oak flooring. The scope also included to refinish our existing red oak floor.

The floors were sanded, water-popped, stained with Minwax Special Walnut from Home Depot, first coat of Synteko Swedish, second Glista Gold Seal, and then Light Scent Glitsa Gold Seal. The contractor did a third coat because there was debris and puddling in the second coat. The work was not continuous since our whole house was being remodeled. Weeks would pass between the installation, sanding, and coating. Rosin paper and cardboard protection was laid down between the major steps to protect the floor from other trades.

The third coat (Low Scent Glitsa Gold Seal) was applied in March 2016. A few months later I began noticing blistering/bubbling like this:


More concerning is what looks like a mismatch in red oak grade. Here are pictures of the original floor with the recent stain and finish.




I will continue below because of the four URL limit per post.

Continuation from above.

Here are pictures of the newly laced-in floor with the same stain and finish. Please note lighting is not the same as the pics above.




To the right of the gate is the newly laced-in floor and the existing floor is to the left.


What grade oak would you say is the existing floor and the laced-in floor floor?

Do you know what could be causing the finish bubbling?

Thank you.

Sorry that you have some spots in your refinished floor. These spots usually result in the floor being cold when the finish is applied. The narrow board width makes for more potential for this type of problem. As the finish cures it will shrink and spots will be less noticeable. Scraping smooth and then adding a touch-up coat with the grain will be the solution.
The wood looks like select red oak as well as the original floor. Wood will darken with exposure to light and a match will occur over time. There may be more straight-grain strips in the new wood vs plain sawn, but this only depends on what part of a tree is being milled and how it goes through the mill.
This is a nice looking floor.