Ok, so first off.
Use thicker plywood.
I wasn’t happy with how bendy and warpy this plywood was.
Also, use Tounge and Groove. I’m not sure what I was thinking when I ordered this stuff, but clearly I wasn’t thinking about having a sturdy floor.
Steps
- Align plywood along wall
- cut last piece
- use excess to start next row
- (to make sure you..) overlap your seams so no seams are butting against each other
- screw the plywood to it
- don’t hit your radiant tubes!
Plywood Over Sand Mass Radiant Floor