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.
To solve this problem, construct a raised platform from 2×4 or 2×6 lumber placed on edge, add insulation between the joists, and then cover it with 1/2″ plywood. Here’s how to go about it:
- Cut 2” thick lumber to length for the frame.
- Attach metal covers to electrical junction boxes, and move any electrical wires out of the way or notch the frame to fit around them.
- Build a frame on 16” centers perpendicular to the attic floor joists.
- Screw the frame to the joists to secure it in place, making sure not to screw into electrical wires.
- Full the spaces between the frame members with insulation.
- Rip 1/2″ thick plywood to 24″ widths so it will fit up the attic stairs.
- Screw the plywood to the frame.
Watch this video to find out more.
- How to Build Storage Shelves in Your Attic (video)
- DIY Storage Solutions for Your Home (video)
- How to Organize and Add Storage to Your Garage (video)
- How to Install Closet Shelving (video)
To properly add an attic storage deck, start by measuring the largest area available that is not hindered by any ductwork; and, preferably, can avoid any existing roof support. To eliminate any potential problems with wiring or insulation, use two by four or two by six lengths to create a subfloor system for the new decking. These pieces can be placed perpendicular to the ceiling joists. Screwing the two bys to the joists will help prevent any damage to the interior ceiling that could result from hammering.
Place the two bys on edge, and install them to the ceiling joists so that the center of each board is exactly 16 inches away from that of the preceding board. Be careful not to trap a wire between the two bys and the joist. In most cases, you should have enough slack in the wire to move it out of the way. In rare cases, you may need to notch the bottom of the two by to allow the wire to remain exactly where it is.
Once all the two bys for the subfloor are in place, add batts of unfaced insulation between the two bys. If any electrical junction boxes are within the area of the new decking, make sure the box has a cover over it.
The decking material can be half-inch plywood. However, since very few attics have an opening that’s wide enough to pass a full sheet of plywood through, the four by eight sheets should be ripped lengthwise. Be sure to cut the ripped pieces to the proper length before taking them up into the attic.
The decking pieces will be placed directly on top of the newly added two by subfloor, covering any added insulation, and attached using 1¼” drywall screws. Once all the pieces are attached, you’re ready to begin using the newly made storage space.
Just an fyi, It is code to not cover up j boxes, It must be assessable, and covered with a deck not having a hatch is not following that section in the N E C.
We need at least 33 inches to get above all duct work in attic. That creates a problem in support for storage floor and only using support walls below. House is a open floor plan so not a lot of support walls below.
lan to use 2x4x36 (upright) screwed to ceciing joist every 24″ to hold 2x6x12’s up above duct work.
Planned on using the 2×6 to support 2x4x12 on 16″ centers with one end attached to rafters. Sounds like a lot of work. Very tall attic. Entrance is walk-in door from a bonus room over garage. Is this plan (if understandable) workable? Appreciate any feed back. Thank you.
One thing not mentioned here is what screws to use to attach the 2 x 4’s. I have 2 inch wood screws and I am thinking they will do just fine but wanted to double check.
Hi Charles! Yes, 2-inch wood screws will work with this project. Thanks for reading, and good luck with your raised storage area!