Thinner plywood can flex when you walk on it even with 16.
Flooring for attic room.
1 x 6 3 spruce is a step up from pallet quality wood but makes a fine usable floor in an unfinished attic space.
For example if your attic is accessed through a hatchway or dropdown ladder you can install a few thin plywood panels across the joists or attic trusses within reach of the hatchway.
Also if you do build a room or rooms in the attic one day the floor insulation will help soundproof the attic space.
Air from rooms below will not escape rapidly into the attic.
To solve this problem construct a raised platform from 2 4 or 2 6 lumber placed on edge add insulation between the.
Joist dimensions are only part of the equation.
Adding a floor to an attic can increase storage space or create a new room.
First if you never build a room in the attic the insulation in the floor area will save energy costs.
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 plywood.
If you don t need additional storage think of flooring an area less than the entire attic such as a small section around the attic door opening.
You also need to ensure that the joist spacing is adequate.
Lay a plywood base first of 5 8 inch to 3 4 inch thick plywood.
To avoid overhead noise in the rooms below the attic it might be best to carpet the area.
Partial attic flooring.
Before you start creating a floor for your attic you must make sure that it can handle the additional load.
If you are just looking for extra storage space consider the minimalist approach of installing flooring in just part of the attic.
Attics are great for storage but flooring directly over the attic floor joists doesn t provide room for the recommended 12 to 16 of attic insulation needed to keep your house cool in the summer and warm in the winter.
Then you ll need to build a grid like structure that can hold up the plywood flooring.
In many cases ceiling joists for dead loads are designed to carry 10 pounds per square foot.
Attic joists that are made from 2x8s may be acceptable for building your attic floor but because every room is variable there are no absolutes.