How do you fit a replacement floorboard into an existing floor?

Sand or shave the tongue of the replacement piece for easier fitment, and remove the lower part of the groove side plus a little more. Apply glue to all connection points using PVA cross-linked or polyurethane adhesive, tap into place using a piece of flooring under the hammer head, and top nail to secure. FSA Network floor sanders have the skills and tools for seamless board replacement.