u/kirkssodawater

G'day, I'm building a weightlifting platform and I'm wondering what kind of screws would be best for the different layers.

The bottom two layers are 4 slabs of 19mm OSB, cross hatched (2 on the bottom side by side then 2 on top laid across). The top layer has a single slab of 28mm keruing hardwood plywood in the middle with 6mm MDF boards and 22mm horse stall rubber mats on either side. So down the middle the layers from top to bottom are 28mm keruing hardwood plywood, then 19mm OSB, then 19mm OSB. On both sides they are a 22mm rubber mat, then 6mm MDF, then 19mm OSB, then 19mm OSB.

All wood has been coated with polyurethane as it's going on my garage floor.

What kind of screws should I use to secure the two layers of OSB together?

What kind of screws should I use to secure the keruing to the OSB?

What kind of screws should I use to secure the rubber through the MDF to the OSB?

I'm planning on pre-drilling holes because I don't want any of the pieces splitting.

G'day, I'm about to crack on with reorganising my garage gym and properly setting it up and was wondering what some of your opinions and experiences are with trying to cheaply soundproof masonry walls? Was looking at the acoustic panels from Bunnings but they're quite expensive if I would cover the entire garage. How are the foam square panels if I just drilled them in? Or would the thicker mason bricks be enough to dampen gym sounds as they are?

Scarborough/Trigg are pretty rough but look workable, going to check out Cott now but no one seems to be capitalising on this big swell. Are there any beaches with rideable conditions?