No matter what the spacing is on your ceiling joists 3 4 inch plywood should be used if you plan on walking on it.
Attic walkway plywood.
If you plan on placing the plywood around the perimeter of the opening or door and using it only to store light boxes or materials 1 2 inch thick plywood should suffice.
The surface itself just has to be strong enough to handle your weight along with tools and gear.
Continue the process until the flooring is finished.
The plywood should be laying on top of the subfloor with no overhang.
After that screw it in place using the 2 inch deck screws.
The intent is to lay down the boards and the ends should attach to a ceiling rafter.
A 4 foot long plywood strip will need at least 8 screws on it.
Ensure that the end of the first plywood sheet lands on a piece of 2x leaving enough room to position the.
Apply construction adhesive on one side and place it on the horizontal chord.
Once the boards are in place place more screws placed 16 inches 40 64 cm apart to hold the plywood to the subfloor frame.
Place the first plywood sheet on top of the 2x structure starting by the attic entrance.
Once you re done laying down all of the plywood your attic floor is finished.
The thinner plywood is acceptable when the joist spacing is 16 inches.
We used leftover plywood scraps to build ours an attic walkway also needs enough support.
If you plan to finish the floor in the attic and turn the room into a living space however you should always use 3 4 inch.
Installing attic flooring for light storage only if your attic joists won t bear the weight necessary to finish out a living space but the engineer cleared them to support floor decking for light.
An attic walkway doesn t have to be pretty or expensive.
The first plank is placed at the entrance of the attic walkway on the first horizontal chord.