12×18 Lean to Shed Plans

This step by step diy project is about 12×18 lean to shed plans. I designed this simple lean to shed that has a footprint of 12×18. This garden shed is built on a sturdy 2×4 framing, every 16″ on center and it features overhangs on all sides. Moreover, the shed has double front doors to the front and a side window. The roof is built from 2x8s, placed every on center. 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. If you have all the materials and tools required for the project, you could get the job done in about a day. See all my Premium Plans HERE.

Projects made from these plans

12×18 Lean to Shed Plans

Building-a-12×18-lean-to-shed

Cut & Shopping Lists

• A – 2 pieces of 2×6 lumber – 216″ long, 15 pieces – 141″ long FRAME
• B – 8 pieces of 6×6 lumber – 108″ long SKIDS
• C – 5 pieces of 3/4″ plywood – 48″x96″ long, 2 pieces – 24″x48″ long, 1 piece – 48″x48″ long FLOOR
• D – 2 pieces of 2×4 lumber – 137″ long, 1 piece – 144″ long, 10 pieces – 91 1/2″ long, 4 pieces – 25″ long, 2 pieces – 48″ long, 4 pieces – 7 1/2″ long, 4 pieces of 2×6 lumber – 35″ long SIDE WALL
• E – 2 pieces of 2×4 lumber – 137″ long, 1 piece – 144″ long, 10 pieces – 91 1/2″ long SIDE WALL
• F – 2 pieces of 2×4 lumber – 216″ long, 1 piece – 209″ long, 17 pieces – 91 1/2″ long BACK WALL
• G – 2 pieces of 2×4 lumber – 60″ long, 1 piece – 209″ long, 1 piece – 216″ long, 12 pieces – 91 1/2″ long, 2 pieces – 78 1/2″ long, 8 pieces – 7 1/2″ long, 2 pieces of 2×6 lumber – 99″ long FRONT WALL
• G – 2 pieces of 2×4 lumber – 216″ long, 15 pieces – 32″ long TOP FRONT WALL
• F – 13 pieces of T1-11 siding – 48″x96″ long, 2 pieces – 24″x96″ long, 1 piece – 16″x48″ long, 4 pieces – 35″x48″ long, 1 piece – 24″x35″ long SIDING

• 8 pieces of 6×6 lumber – 10′
• 2 pieces of 2×6 lumber – 18′
• 15 pieces of 2×6 lumber – 12′
• 6 pieces of 3/4″ plywood – 4’x8′
• 7 pieces of 2×4 lumber – 18′
• 6 pieces of 2×4 lumber – 12′
• 2 pieces of 2×6 lumber – 8′
• 2 pieces of 2×6 lumber – 10′
• 61 pieces of 2×4 lumber – 8′
• 17 pieces of 5/8″ T1-11 siding
• 8d galvanized screws
• 3 1/2″ screws
• rafter ties
• wood glue, stain/paint, wood filler

Tools

 Hammer, Tape measure, Framing square, Level

 Miter saw, Drill machinery, Screwdriver, Sander

 Safety Gloves, Safety Glasses

Time

One week

Related

• PART 1: 12×18 Lean to Shed Plans
• PART 2: 12×18 Lean to Shed Roof Plans

Make sure you follow me on Facebook to be the first that gets our latest plans and for some other exclusive content. Also, follow me on Pinterest to get many ideas for your backyard from all the internet! Check out my YouTube channel! See how you can Support MOP  with no extra costs to you. 

Building a 12×18 lean to shed

Floor-frame-for-12×18-shed

First of all you have to assemble the floor frame for the lean to shed. Use 2×6 boards for the joists and cut them at the dimensions shown in the diagram. Place the joists every 16″ on center and make sure the corners are square. Drill pilot holes and insert 3 1/2″ screws to assemble the frame of the floor.

Fitting the skids under the 12×18 shed

Use 6×6 lumber for the skids. Place the skids under the floor frame and use rafter ties to lock them into place. You can use 4×4 skids as well, if you want to keep the costs down

Floor sheets – 12×18 shed with lean to roof

Use 3/4″ tongue and groove plywood sheets for the floor of the lean to shed. Cut the sheets at the dimensions shown in the diagram and lay them to the floor frame of the shed. Align the edges flush and insert 1 5/8″ screws to lock them into place tightly. Insert the screws every 8″ along the framing.

Back-wall-frame-12×18-shed

Use 2×4 lumber for the back wall frame. Cut the studs at 91 1/2″ and then secure them to the plates with 3 1/2″ screws or nails. Place the studs every 16″ on center and make sure the corners are square.

Side-wall-with-frame—12×18-lean-to-shed

Next, we need to assemble the side wall that has a window. You 2×4 lumber for the frame, as well. Drill pilot holes through the plates and insert 3 1/2″ screws / nails into the studs. Frame the window with the double headers (sandwich 1/2″ plywood between the 2x6s beams). Remember that you can adjust the size of the windows to suit your needs.

Side-wall-frame-for-12×18-lean-to-storage-shed

Assemble the other side walls in the same manner described above. Place the studs every 16″ on center, just you do it when building a house.

Front-wall-frame—12×18-lean-to-shed

Building the front wall is a more complex job, as you need to frame the door opening. In addition, you need to fit the double header to the top of the opening. Build the header from 2 pieces of 2×6 lumber and 1/2″ plywood. Glue the components of the header together and insert screws to lock everything tightly. You can adjust the size of the double doors to suit your needs.

Assembling the frame of the 12×18 shed

Fit the frames to the floor of the shed. Align the edges flush and make sure the corners are square. In addition, use a spirit level to make sure the walls are plumb. Drill pilot holes through the bottom plates and insert 3 1/2″ screws into the floor of the lean to garden shed. Don’t forget to lock the adjacent walls together, as well.

Side wall siding sheets – 12×18 shed

Use 5/8″ T1-11 siding sheets for the side walls. Align the edges flush and leave no gaps between the sheets. Insert 8d nails, every along the framing. Maker the cuts around the window opening.

Front wall siding sheets – 12×18 shed

Fit the sheets to the front of the 6 cord firewood shed and make the cuts around the double doors opening.

Back wall siding sheets – 12×18 shed

Attach the siding sheets to the back of the shed. Align the edges flush and insert 8d galvanized nails to secure the sheets to the wall frames. Align everything with attention and insert the nails every 8″ along the studs.

Top front wall frame

Next, use 2×4 lumber for the top wall frame. Drill pilot holes through the plates and insert 3 1/2″ screws into the studs.

Fitting the top front wall

Fit the wall frame to the front of the storage shed. Align the edges flush, drill pilot holes through the bottom plate and insert 3 1/2″ screws into the shed frame. Plumb the walls vertically with a spirit level.

Front wall top siding sheets

Fit the T1-11 siding sheets to the top of the front shed wall.

12×18-lean-to-shed-plans

This shed is built on a super strong and durable 2×4 framing. This is the perfect addition to your property, if you have many items to store. The double front doors help you have an easy access to the interior. You can also build a shed ramp and use this shed for storing bikes, for example. In addition, you can add windows to this shed, so you let more light inside the structure.

How-to-build-a-12×18-lean-to-garden-shed

12×18 Lean to Shed Plans – overall dimensions

Don’t forget to take a look over PART 2 of the project, so you learn how to build the roof for the shed. If you build this, I would love to see your project. If you want to get PREMIUM PLANS for this project, in a PDF format, please press GET PDF PLANS button bellow. Thank you for the support.

This woodworking project was about 12×18 shed plans. 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.

EXPLORE MORE IDEAS FOR: