How to Build Attic Flooring on Joists — The attic is one of the most unused and under-designed space of a home. Most people store clothes, antiques, junk, photo albums and many of their long forgotten things in this rather dingy area, often known as dead load.
However, you can easily transform your attic by remodeling its floor using joists to create a safe and stable flooring system. The joists must have enough strength to support the load anticipated in the future as well. Raised floors are more hardy under the foot with scope for plumbing, insulation, heating equipment, wiring, and more.
In fact, a raised plywood attic floor over insulation lowers your home’s energy cost. Proper attic flooring over the insulation keeps some storage space as well.
Limits to Flooring Finishes
A raised floor on the upper levels of the house is usually constructed of lighter materials; however, the underside of the ceiling should be sturdy to bear the weight of the load. The floor framework is mostly made of wood joints running parallel to one another at regular intervals. When joists spacings are wider, they should be deeper as well to limit stress and deflection under the load. Most floor joists are typically spaced 2 by 8s, 2 by 10s, and 2 by 12s. New homes install I beam-shaped joists.
How to Install Attic Flooring?
Installing flooring material over the attic doesn’t quite leave room for the recommended insulation space needed to provide efficient home energy. A raised platform of lumber in dimensions of 2×4 or 2×6 with insulation placed between joists and covered up with a 12-inch plywood, helps build the right flooring. During this time, take these necessary precautions:
- Check for stains under the attic, which indicates a leak in the roof.
- Reroute vent fan ducts outwards to prevent warm air inside the attic.
- Additional ventilation may be needed if you find signs of condensation on the roof.
- Inspect the space for storage – more the load anticipated, more sturdier should be the attic flooring.
Joists that are only 2x4s may not be hardy enough to bear too much weight. For 2x6s joists, you can get away with some relatively light stuff. Joists of 2x8s or larger are able to support more weight. The overall strength of the flooring joists depends not only on the size of the span, but also on the distance between the support. If you find that you’d like to store more weight, consider adding an OSB for attic floor.
A subfloor acts like a base and serves as a construction platform. Boards are laid either diagonally or at right angles across joists.
Determine Limitations of what Finish Materials you can Use for Plywood Subfloors
Here are the steps to consider when flooring an attic:
Prepare the Space
Even before you start working on your attic flooring ideas, check to see whether the ceiling will be able to handle the weight of the new floor along with storage and people walking around. This is an important step based on which you can design your course of action in terms of attic flooring. Call contractors specialized with attic flooring in your area to get a better understanding of the condition before making any structural changes to the floor.
Measure Both the Cut and Space
Purchase lumber boards from a hardware store and measure up the flooring dimensions. Mark up the measurements and make the cuts accordingly using a handsaw or a circular saw. Continue to cut the boards until you have a good amount of boards ready to be laid on the subfloor. Make sure you accurately measure any additional space required around electrical wirings and outlets.
Clear Insulation to Create Subfloor
Remove the insulation and set it aside. Next, see how many boards you need to create the flooring grid. Place the panels parallel to each other and make sure they are on a level with the ceiling. Screw the boards down into the ceiling framework using an electric screwdriver. Create the subfloor now placing perpendicular joints on the already created first set of board. The finished subfloor should look like a grid.
Laying the Plywood Flooring
Place the insulation back and prepare for the top layering of the attic floor. Start off by measuring the panel to be placed as a layer. Again cut the lumber according to your measurements. As you do this, make sure that the plywood is straight. Keep in mind that the plywood floor has to set in securely around obstructions and outlets. Once you’re done with laying down the top panels, your attic floor is finished.
Use of Joists in Attic flooring
Covering the ceiling joists in the attic using plywood is a cheap way to make better use of the wasted space in your house. The subfloor installation is easy. Precise measurement is the most difficult as you need to consider all underlying obstructions carefully before proceeding with your plans. Also, creating an access route to your attic such as a door or ladder is probably the most expensive. Most homes will have a ladder of stairs that leads up to the attic.
Joists carry the weight of the walls, furniture, and people on them. When a load is applied on a joist, it creates a tension in the wood along the top edge. Even a little drill in the wrong place can cause the structure to weaken, resulting in annoying bounce and sag you experience every time while crossing the weakened floor. When planning for your joist flooring, make sure you leave enough space to create access routes for your attic. Follow the rules to keep your floor in good shape and prevent any kind of impact. With good planning you can avoid making these mistakes that are not just costly, but obstructive as well.
Once the attic is created and lighting is installed, you can plan the interior of the space if you happen to double it as a storage plus an extra room. As a storage area, you may want to place cabinets and horizontal space to keep it organized.