How to Build Loft Stairs

* 2x12 dimensional lumber (for the stringers)

* 2x4 dimensional lumber (for the tread risers)

* 2x6 dimensional lumber (for the treads)

* 1/2-inch plywood (for the subflooring)

* 1/4-inch carriage bolts

* 1/4-inch washers

* 5-inch wood screws

* Finish nails

* Circular saw

* Miter saw

* Drill

* Sander

* Level

* Measuring tape

* Safety goggles

* Dust mask

Step 2: Determine the location and size of the stairs.

The first step is to determine where you want to build the stairs and how big they need to be. The best way to do this is to measure the height from the floor to the loft and then divide that number by the desired rise per step. The result will be the number of steps you need to build. Once you know the number of steps, you can determine the length of the stringers by multiplying the rise per step by the number of steps.

Step 3: Cut the stringers.

The stringers are the main support beams of the stairs. They are typically made from 2x12 dimensional lumber. The first step is to cut the stringers to the correct length. The length of the stringers should be equal to the height from the floor to the loft minus the thickness of the subflooring and treads.

Step 4: Attach the stringers to the floor and loft.

Once the stringers are cut to size, they need to be attached to the floor and the loft. The best way to do this is to use 5-inch wood screws. Predrill holes for the screws to prevent the wood from splitting.

Step 5: Install the tread risers.

The tread risers are the vertical pieces of wood that connect the steps. They are typically made from 2x4 dimensional lumber. The first step is to cut the tread risers to the correct height. The height of the tread risers should be equal to the rise per step. Once the tread risers are cut to size, they can be attached to the stringers with 5-inch wood screws.

Step 6: Install the treads.

The treads are the horizontal pieces of wood that you step on. They are typically made from 2x6 dimensional lumber. The first step is to cut the treads to the correct width. The width of the treads should be equal to the distance between the stringers. Once the treads are cut to size, they can be attached to the stringers with 5-inch wood screws.

Step 7: Install the subflooring.

The subflooring is a layer of plywood that goes over the treads. It helps to distribute the weight of the people walking on the stairs and prevents the treads from sagging. The first step is to cut the subflooring to the correct size. The subflooring should be the same size as the treads. Once the subflooring is cut to size, it can be attached to the treads with finish nails.

Step 8: Sand the stairs.

Once the stairs are built, they need to be sanded to make them smooth. Sand the stairs with a 120-grit sandpaper until they are smooth to the touch.

Step 9: Finish the stairs.

You can finish the stairs with any type of finish that you like. Some popular finishes include paint, stain, or polyurethane.