Q: I recently inspected a 50 year old house with original red oak flooring. We found extensive termite damage in crawl space. Some of the 1×6 pine subfloor was severely damaged (crumbling). Except for a few small areas the finished oak floor was in good condition. What is the best way to repair/replace the subfloor?
Do we have to tear up the finish oak? Can the repair be done from underneath in 2-4 ft.height crawlspace? Do we need new subfloor between the 1 1/2inch floor joist and the finish oak? Can we just sister on ledger strips to the existing floor joist (treated) and add new subfloor between the floor joist?
A: If the termites snacked out on the sub floor, I would suspect the oak strip probably is somewhat spongy since it isn’t sitting on much. My gut feeling is that it is best in the long run to remove the oak where needed, remove the damaged sub and screw down plywood. Strange creatures. I just finished a job with termite damage. They pretty much left the soft woods alone and went straight for the Seaman Kent oak strip!