I'm currently rippout our some old engineered hardwood and the 5/8 particle board it's glued too. Our subfloor is 1/2 OSB. I'm installing 23/32 plywood overtop as my underlayment for my new 5/16 Brazillian Walnut floors. I'm leaving roughly 1/8" gaps between panels and 1/4" at all vertical surfaces. Sometimes the gaps between panels are up to a 1/4 inch as well depending on how straight I have the panels cut.
Should I fill the gaps between panels with silicon or anything like that and sand the edges?