How to Build a Shed

Create the Outer Perimeter of the Floor Frame

Cut 3 inches off of one end of two of the pressure-treated 2-by-8 boards. Place them on the ground parallel to each other. Then place 2 full-length pressure-treated 2-by-8s perpendicular to those. With the framing hammer and 16d galvanized nails, nail the four boards together to form a square shape that measures 8 feet long by 8 feet wide. Use two nails per end.

Mark the Shed's Footer Locations

Move the floor frame to the desired shed location. Measure the floor frame for the square by measuring across the two diagonals. Gently push the frame into a square so that the two diagonal measurements match.

Firmly place the four concrete footer blocks in the inside corners of the frame. Drive a wood stake at the outside corner of each of the frame's four corners to establish center points. Remove the frame and blocks.

Install the Shed's Footer Blocks

After removing the concrete blocks, dig a hole at each spot about 20 inches by 20 inches by 8 inches deep, using the stake as a center-point reference.

Fill each hole with gravel until the gravel reaches ground height. Place the concrete blocks on each gravel bed. Level each block with the bubble level. Place the frame's corners on each block and level by adding or removing gravel from underneath individual blocks as needed.

Install and Frame the Shed's Floor

Double up two opposing sides of the floor frame with two 2-by-8 boards cut to fit inside the frame at each side. These act as rim joists to strengthen the two ends of the frame that will carry the weight of the inner joists. Nail into place with the 2 1/2-inch nails.

Joists will extend from one rim joist to the opposite rim joist. Mark five locations on each rim joist at 16 inches on-center. Install joist hangers at each spot with the 1 1/2-inch nails. Insert six of the pressure-treated 2-by-8 boards into the joist hangers and secure with 1 1/2-inch nails.

Install Shed's Flooring

Square up the shed floor frame one last time up to a 1/8-inch tolerance level. Install the two tongue-and-groove OSB sheets on top, perpendicular to the joists. Secure the OSB throughout the perimeter and joists every 8 inches with 1 1/2 inch nails.

Frame the Back Gable End

The two wall sides of the shed with triangular peaks are the gable ends. Because the floor area is 8-foot by 8-foot, this gives you a convenient template for beginning to frame the gable end wall.

Lay one 2-by-4 board on edge along one of the sides of the floor frame. Dry-fit two other 2-by-4 boards along the two adjacent sides of the floor, making a U-shape. In the center, dry-fit four more 2-by-4 boards so that they are parallel to the two sides of the U-shape. All 2-by-4 boards should be spaced at 16 inches on-center.

Along the top side, lay two more 2-by-4 boards on-end over the top of this assembly, forming a broad obtuse angle, around 150 degrees. Use your speed square to confirm the angle. Mark the six 2-by-4 boards that run into this triangle with the pencil. Also, mark the angle on the two 2-by-4 boards that form the triangle.

With the electric miter saw cut angles on the six vertical 2-by-4 boards and on the two 2-by-4 boards that form the angle. Dry-fit all lumber again and nail into place with 3 1/2-inch nails.

Frame the Front Gable End

Frame the front gable end as you did the back gable end, though with some exceptions to accommodate a door opening.

Do not use the two center 2-by-4 boards. Instead, slide them over to double up each of the two 2-by-4 boards that frame the door opening. Also, use two 2-by-4 boards across the top of the door opening to form a door header. Adjust all studs accordingly to fit the pre-built double door.

Mount the Gable Ends on the Floor Frame

Tip to vertical each of the gable ends. Nail ends to the floor with 3 1/2-inch nails. Make sure that the nails penetrate the frame and not just the OSB sheathing.

Frame the Side Walls

Walls will be framed with four 2-by-4 boards forming a rectangle, with three 2-by-4 boards forming vertical interior studs.

Space all boards at 24 inches on-center. Tip the side walls to vertical. Nail side walls to the floor frame with 3 1/2-inch nails. Nail the gable ends to the side walls, also with 3 1/2-inch nails.

Install the Ridge Board

Have a helper hold a 2-by-8 board between the two gable peaks. You should then climb your ladder to each peak and, from the opposite side, drive 3 1/2-inch nails into the ends of the ridge board.

Install Rafters and Ties

Install five pairs of rafters spaced 16 inches on-center, running from the ridge board to the top plates of the two side walls. Rafters will need to be cut at an angle on each end to meet the ridge board and the top plate. Nail into place and secure with metal hurricane ties.

Add Ceiling Joists for Support

Unlike a roof truss system, which prevents walls from bowing, the simpler ridge-and-rafter system employed here does not do this.

To keep the walls from separating, nail three 2-by-4 boards from one side wall to the other side wall. Later, if you wish, these can be used for ceiling storage.

Install Sheathing on Walls and Roof

The 10 sheets of 1/2-inch OSB sheathing will be dispersed among the four walls and the roof.

Each wall will receive two sheets. Hang horizontally and nail into place with 1 1/2-inch nails.

The roof will receive two sheets. Before nailing sheathing on the front gable end, mark and cut for the door opening. Install the door.

Install the Siding

Finish the walls with tongue-and-groove shiplap pine siding installed horizontally. Trim around the door.

Install the Roofing

Rolled asphalt roofing, also known as mineral-surfaced roofing (MSR), is easy to install and inexpensive.

When installing the roofing material, start at the bottom and work upward. It's best to overlap your sections by 8 inches to 12 inches.