Attic Subfloor Thickness
Standard joist spacing for the installation of attic flooring materials is 16 inches on center oc meaning the distance from the center of one joist to the center of the next joist is 16 inches.
Attic subfloor thickness. You also need to ensure that the joist spacing is adequate. The recommended thickness of the plywood subfloor is governed by the spacing of the joists. The access on all examples is folding stairs or ceiling scuttles. Take the measurements for your subfloor and measure enough plywood so that you can cover the entire frame.
Ask question asked 8 years 9 months ago. Attic joists for live loads. Active 8 years 9 months ago. Plywood comes in 4 by 8 foot sheets with thicknesses ranging from 1 4 to 1 1 4 inches.
Some have single 7 16 osb spanning 24 where the attic is only for storage. What s the minimum reasonable thickness for subfloor in my attic. Attic storage might be a good idea but other issues such as insulation joist spacing and intended usage should be taken into consideration. Measure the plywood and attic door.
The thickness that builders use most often for subfloors is 3 4 inch and when they need extra reinforcement. I want to install 4x8 sheets of t g plywood in my attic for extra storage room but there are so many different thicknesses. Joist dimensions are only part of the equation. There will be extremely minimal traffic on this floor as i will.
Plywood flooring thickness is important for proper weight distribution. Purchase half inch 1 27 cm thick plywood to act as your flooring. You ll need to make sure that the plywood can fit through your attic door. Some experts suggest that 15 32 inch plywood should be standard if the underlying floor joists are spaced 16 inches apart or less but slightly thicker 3 4 inch plywood should be used for joists spaced further apart.
Keep in mind that a 4 by 8 sheet of flooring will fit the ceiling joists in either direction. Half inch sheets may be thick enough but 5 8 or 3 4 inches is recommended. Viewed 8k times 6. 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.
Achieving greater r values in attics the higher the r value the better the thermal performance of the insulation.