What would you suggest using best material to seal the gaps? Under closer inspection, I find Hoovie is correct in saying these are not T&G boards and do appear to have a sawdust/resin mix fill, still in tact in most areas I've revealed so far(Except, where you noticed the larger predominant gap.
So should I completely re-grout, removing the old fill and using e.g.. expanding foam/mastic? I assume mastic is very similar to silicone sealant in way? Apologies for my limited knowledge! I'm "Googling" the meaning of these new terms as I go along.
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If im not mistaken, using the small thin sticks sounds it will be at bit of a task on my hands.
I use to work for a business for a couple months that renovates outdoor sun decks. I did pick some experience in this type of trade, but im certainly going to be using caution in this project.
We used to use an epoxy to fill and cover nails/screws, giving flush surface to the deck boards.
I could use this to on my living room floor on any holes, damage, chipping etc. ?
I plan to start tearing away the rest of the carpeting and underlay, removing nails and start the filling work next week end the 12th & 13th.
Then I plan to start the sanding the following weekend.
Long one but thanks for reading and your valued responses so far!
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Nick