We have lifted our original floorboards in our property, we now plan on insulating between the joists and relaying the original boards.

Unfortunately, the floorboards were old and brittle and consequentially many boards have lost small slivers of wood from either the tongue or the groove on the underside of the board.

My idea to salvage as many of the original boards as possible is to lay a thin layer of plywood over the original joists to better support the now weakened original boards. Areas where the tongue or groove of the board are damaged that could potentially split benefit from the additional support of the plywood board.

Can anyone comment on the potential merits or pitfalls of this idea?

  • sounds like a good idea to me. Also use some clear drying wood glue, like Gorilla wood glue to help secure some of the splits in your reclaimed flooring. Jul 31, 2016 at 13:44

1 Answer 1


Two "minor" points... if the plywood is going to genuinely offer support, it probably needs to be at least 1/2". Have you thought about whether that's going to create other problems with clearance, such as at transitions/intersections/door bottoms? Also, assuming that the flooring runs perpendicular to the existing framing (joists etc), if we're really talking about small slivers, such as you describe I'm not at all sure that you need to do anything. Is there no existing subfloor, the flooring is just attached to the joists?

Can you post pics of the typical damage?

  • Here are two 'typical' floor boards. These are both what I am currently considering is acceptable to re-lay.. Typical floorboard Typical floorboard2 Jul 31, 2016 at 20:36
  • @SamWilliams A little too close up for me to figure out what I'm looking at... it's really a matter of how much tongue/groove is broken away. I've reused many pieces of flooring that had damaged edges with no problem, but if you want to post something that show the context of the damage, happy to have another look.
    – PaulBinCT2
    Jul 31, 2016 at 21:56

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.