This step by step diy project is about 12×20 lean to shed shed plans. Today I share free plans for building the 12×20 lean to shed. This shed is large and it comes with double front doors. Check out PART 2 and PART 3 or the project so you learn how to build the roof and the double doors. Make sure you comply with the local codes before staring the project. Take a look over the rest of my woodworking plans, if you want to get more building inspiration.
When buying the lumber, you should select the planks with great care, making sure they are straight and without any visible flaws (cracks, knots, twists, decay). Investing in cedar or other weather resistant lumber is a good idea, as it will pay off on the long run. Use a spirit level to plumb and align the components, before inserting the galvanized screws, otherwise the project won’t have a symmetrical look. See all my Premium Plans HERE.
Projects made from these plans
12×20 Lean to Shed Plans
Cut & Shopping Lists
- A – 5 pieces of 4×4 lumber – 240″ long SKIDS
- B – 2 pieces of 2×6 lumber – 240″ long, 16 pieces – 141″long FLOOR
- C – 6 pieces of 3/4″ plywood – 48″x96″ long, 3 pieces – 48″x48″ long FLOORING
- D – 2 pieces of 2×4 lumber – 72″ long, 1 piece – 244″ long, 1 piece – 233″ long, 10 pieces – 79 1/2″ long, 2 pieces – 74″ long, 2 pieces of 2×6 lumber – 99″ long FRONT WALL
- D – 2 pieces of 2×4 lumber – 137″ long, 1 piece – 144 long, 7 pieces – 79 1/2″ long 2xSIDE WALL
- E – 2 pieces of 2×4 lumber – 240″ long, 1 piece – 233″ long, 13 pieces – 79 1/2″ long BACK WALL
- E – 2 pieces of 2×4 lumber – 240″ long, 13 pieces of 2×4 lumber – 21″ long TOP BACK WALL
- G – 15 pieces of T1-11 – 48″x84″ long, 5 pieces – 24″x48″ long, 1 piece – 8 1/2″x48″ long SIDING
- 5 pieces of 4×4 lumber – 20′
- 2 pieces of 2×6 lumber – 20′
- 16 pieces of 2×6 lumber – 12′
- 8 pieces of 3/4″ plywood – 4’x8′
- 6 pieces of 2×4 lumber – 12′
- 7 pieces of 2×4 lumber – 20′
- 42 pieces of 2×4 lumber – 8′
- 17 pieces of T1-11 – 48″x96″
- 8d nails, 2 1/2″ screws, 3 1/2″ screws
- wood filler , wood glue, stain/paint
Hammer, Tape measure, Framing square, Level
Miter saw, Drill machinery, Screwdriver, Sander
- PART 1: 12×20 Shed Plans
- PART 2: 12×20 Shed Roof Plans
- PART 3: 12×20 Lean to shed doors Plans
Building a 12×20 lean to shed
The first step of the diy outdoor project is to build the floor frame for the 12×20 shed. Cut the joists from 2×6 lumber at the dimensions shown in the diagram. Lay the joists on a level surface and then align the edges flush. Make sure the corners are square and then drill pilot holes through the rim joists. Insert 3 1/2″ screws to lock the components together tightly. Use at least 2 screws for each joint.
Next, fit 4×4 skids under the floor frame. Place the skids equally spaced and then lock them to the frame with rafter ties. Select the location for the shed and remove the vegetation layer. Level the surface thoroughly.
Fit the 3/4″ plywood sheets to the floor of the shed. Align the edges flush and leave no gaps between them. Insert 1 5/8″ screws to lock the sheets along the joists, every 8″.
Building the shed wall frames
Frame the front wall using the information from the diagram. Cut the components from 2×4 lumber at the dimensions shown in the plans. Drill pilot holes through the plates and insert 3 1/2″ screws into the studs. Use 2×6 lumber for the double header and fit 1/2″ plywood between the beams. Drill pilot holes and insert 2 1/2″ screws to assemble the double header. You can adjust the size of the door opening to suit your needs.
Build the side walls for the shed from 2×4 lumber. Cut all the components at the right dimensions and the lay them on a level surface. Drill pilot holes through the plates and insert 3 1/2″ screws into the studs. Place the studs every 24″ on center.
The next step of the project is to build the side wall frames from 2×4 lumber. Cut the components at the right dimensions and then lay them on a level surface. Drill pilot holes through the plates and insert 3 1/2″ screws into the studs. Check if the corners are square and place the studs every 24″ on center, as shown in the diagram.
Fit the wall frames to the floor of the shed. Align the edges with attention and plumb the walls with a spirit level. Drill pilot holes through the bottom plates and insert 3 1/2″ screws into the floor. Joint the adjacent walls together tightly with 2 1/2″ screws, after drilling pilot holes.
Assembling the shed framing
Build the top frame for the back wall from 2×4 lumber. Drill pilot holes through the plates and insert 3 1/2″ screws into the studs. Place the studs every 24″ on center.
Fit the frame to the top of the back wall. Align the edges with attention, drill pilot holes and insert 3 1/2″ screws to lock it into place tightly.
Fitting the shed siding
Fit the T1-11 siding sheets to the sides of the shed. Make the cuts so you can fit the sheets into place Insert 6-8d nails, every 8″ along the framing.
Fit the T1-11 siding sheets to the front of the shed. Make the cuts so you can fit the sheets around the door opening. Insert 6-8d nails, every 8″ along the framing.
Fit the panels to the back of the shed, as well. Leave no gaps between the sheets and align everything neatly. Insert 6-8d nails every 8″ along the framing.
I have lots of other shed projects on the site so I recommend you to browse through all alternatives before starting the building project. See all my shed projects HERE. Moreover, check out PART 2 and PART 3 of the shed, so you learn how to build the roof and the double front doors. If you want to get this project as a PDF file, with 1 Full Cut list and 1 Full Shopping list, please check out the GET PDF PLANS button bellow.
This woodworking project was about 12×20 lean to shed plans free. If you want to see more outdoor plans, check out the rest of our step by step projects and follow the instructions to obtain a professional result.
I’m attaching at 12 x 20 shed to an existing building.
I am in the process of building this shed. The amount of t1-11 is wrong. It doesn’t account for the angles on the side.
Really? How about you look at PART 2 of the project, you have there a shopping list, as well.
I am going to build this shed, but I want to raise the tall side of the building to 12 feet, to give a stronger pitch, as well as more indoor “head” space. Are there any measurements or angles I should be aware of or pay extra attention to when making this change? I also intend on adding 4x6x12 beams along the tops of the 8 foot walls as load bearing beams. so I can hang chairs inside, also for a cabin feel. Are there any (not so obvious) considerations I should be aware of when adding this feature? I definitely plan on adding extra framing under the beams to actually make them load bearing, I am more curious how to incorporate them into the roof line/added 4′ wall.
I appreciate all of your work and advice! thanks for helping me make this studio come to life!