12 x 12 Storage Shed Plan

Introduction

You'll never run out of room to keep the yard tools and equipment inside a weather-proof and safe building with this 12' x 12' shed. It has a double-door entry with an entrance ramp to ease putting things in and taking them out. Just wheel the bicycle inside, as well as anything you can put on a dolly. Each wall measures 12 feet, which nets you 144 square feet of convenient storage space. Even though it's large, it's a project that an inexperienced builder can tackle.

Materials you’ll need

  • Concrete
  • Bricks
  • Pressure-Treated Lumber
  • Pressure-Treated Board
  • Plywood
  • Building paper
  • Asphalt shingles
  • Wood siding boards
  • Door hinges
  • Door Pulls
  • Surface Bolts
  • Galvanized nails
  • Wood screws

Step 1 – Foundation Preparation

1.1 Clear the area where you want to build the shed and layout for the foundation. Use the below illustration as a guide.

1.2 For the foundation, dig the trenches at least 1 foot wide and 1 foot deep.

1.3 Fill the trenches to ground level with concrete and let cure, or harden. Since curing times vary between brands, read the packaging for recommended curing times.

1.4 Once the concrete has cured, use standard-sized bricks and lay them across the foundation. You will need roughly 170 bricks for this step.
12x12 storage shed foundation preparation

Step 2 – Framing The Floor

2.1 Assemble the frame using 1 1/2″ x 7 1/4″ pressure-treated lumber. You will need nine boards cut to 11′-9″ that will be the joist.

2.2 Secure the beams with 8×5″ wood screws.

2.3 Using a speed square or carpenter’s square, check the corners to make sure they are 90°.
12x12 storage shed floor framing

Step 3 – Install the Plywood Floor

3.1 Prepare the 9/16″ plywood for the floor sheathing according to the drawing. You will need three 3′-7 1/4″ x 8′ sheets, three 3′-7 1/4″ x 4′ sheets, one 1′-2 1/2″ x 4′ sheet and one 1′-2 1/2″ x 8′ sheet.

3.2 Secure the plywood with 2″ wood screws.
12x12 storage shed plywood floor installation

Step 4 – Assemble Front Wall Frame

4.1 Using 1 1/2″ x 3 1/2″ and 3 1/2″ x 3 1/2″ pressure-treated lumber, construct front wall frame using the drawing below as a reference. You will need three boards cut to 11″ that will be the cripple studs, one board cut to 5′-4″ that will be the door header, ten boards cut to 6′-11″ that will be the studs, two boards cut to 3′-4″ that will be the bottom plates and one board cut to 12′ that will be the top plate.

4.2 Connect the beams with 2×4″ wood screws.

4.3 Using a speed square or carpenter’s square, check the corners to make sure they are 90°.
12x12 storage shed front wall framing

Step 5 – Assemble Back Wall Frame

5.1 Using 1 1/2″ x 3 1/2″ and 3 1/2″ x 3 1/2″ pressure-treated lumber, construct back wall frame using the drawing below as a reference. You will need eleven boards cut to
6′-11″ that will be the studs and two boards cut to 12′ that will be the top and bottom plates.

5.2 Connect the beams with 2×4″ wood screws.

5.3 Using a speed square or carpenter’s square, check the corners to make sure they are 90°.
12x12 storage shed back wall framing

Step 6 – Assemble Side Walls Frames

6.1 Using 1 1/2″ x 3 1/2″ pressure-treated lumber, construct wall frames using the drawing below as a reference. You will need eleven boards cut to 6′-11″ that will be the studs and two boards cut to 11′-5″ that will be the top and bottom plates.

6.2 Connect the beams with 2×4″ wood screws.

6.3 Using a speed square or carpenter’s square, check the corners to make sure they are 90°.
12x12 storage shed side walls framing

Step 7 – Assemble the Roof Frame

7.1 Using 1 1/2″ x 5 1/2″ pressure-treated lumber, cut twenty-two rafters 7′-8 1/2″ long according to the dimensions.

7.2 Using 1 1/2″ x 3 1/2″ pressure-treated lumber, cut nine collar ties 5′-11 3/4″ long according to the dimensions.

7.3 Using 3/4″ x 7 1/4″ pressure-treated board, cut the ridge board 12′ long according to the illustration below.

7.4 Connect the beams with 2×3″ wood screws.
12x12 storage shed roof framing

Step 8 – Assemble the Rafter Bays

8.1 Cut 20 rafter bays 1′- 3/4″ long using 3/4″ x 5 1/8″ pressure-treated lumber.

8.2 Cut the top edge of each stud to connect them with rafters.

8.3 Connect the beams with 2×4″ wood screws.
12x12 storage shed rafter bays assembly

Step 9 – Install Shed Door

9.1 Build the door frames for the shed using 1 1/2″ x 3 1/2″ pressure-treated lumber and secure with 5″ wood screws. You will need two boards cut to 5′-11 3/4″ that will be the vertical girts and two boards cut to 2′-3/4″ that will be the horizontal girts.

9.2 Prepare the 9/16″ plywood sheet with dimensions 2′-7 3/4″ x 5′-11 3/4″ for the doors according to the drawing.

9.3 Use 2 1/2″ x 3/4″ pressure-treated lumber for the door trim and fasten with 2″ wood screws. You will need two boards cut to 2′-2 3/4″ and two boards cut to 5′-11 3/4″.

9.4 Using 1/4″ x 3/4″ pressure-treated lumber, cut and install a starter course 2′-2 3/4″ long.

9.5 For the exterior siding on the door, use 1/2″ x 6″ wood siding boards and the illustration below as a reference.

9.6 Assemble siding shields with 2″ galvanized nails.

9.7 Install three 3″ door hinges using 6×1″ wood screws. Finish the installation of the door by attaching 4″ surface bolts and 6″ door pulls.
12x12 storage shed door

Step 10 – Roof Sheathing Installation

10.1 You will need 200 Sq Ft of asphalt shingle roofing.

10.2 Add the metal drip edge to the fascias.

10.3 Cover the plywood with building paper.

10.4 Install asphalt shingle roofing using an industrial stapler.

12x12 storage shed roof sheathing

Step 11 – Decorate the Shed

Now that you’ve finished the shed, you are ready to paint it or finish with a wood stain or preservative.

12x12 gable storage shed

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12x12 storage shed plan