Q: I am planning on installing 3/4′ maple hardwood floors. Currently the subfloor is chipboard. What is the minimum thickness of plywood needed to be applied for the hardwood to install properly? If I decide to remove the chipboard all together, how thick of plywood subfloors will I need? Minimum thickness plywood subfloor?
A: I would screw minimum 3/8 spruce. Half inch is better, but would probably create height issues. I’ve never had a problem with using 3/8′ over chip board. Screw into the joists, of course. If you remove the chip board down to the joists, install 3/4 spruce in it’s place.