Home Shed 12×20 Lean to Shed Roof Plans

12×20 Lean to Shed Roof Plans

by Ovidiu
4.5K views 9 minutes read


This step by step diy project is about 12×20 shed roof plans. This is PART 2 of the storage shed project, where I show you how to build the lean to roof. The lean to roof makes this shed ideal, if you want to save space in the yard and build it next to the property line or to an existing building. Take a look over the rest of my woodworking plans, if you want to get more building inspiration. Remember that you need to select the site for the shed with attention and that you have to comply with a few legal regulations.

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


12×20 Lean to Shed Roof Plans




Cut & Shopping Lists

  • F – 2 pieces of T1-11 siding – 29 1/2″x48″ long, 2 pieces – 21 1/4″x48″ long, 2 pieces – 13″x48″ long SIDING
  • G – 11 pieces of 2×6 lumber – 156″ long RAFTERS
  • G – 2 pieces of 2×4 lumber – 16″ long, 2 pieces – 7 3/4″ long SUPPORTS
  • H – 6 pieces of 3/4″ plywood – 48″x96″ long, 3 pieces – 48″x48″ long, 2 pieces – 12″x96″ long, 1 piece – 12″x48″ long ROOF
  • – 2 pieces of 2×8 lumber – 244 1/4″ long, 2 pieces – 156″ long TRIMS
  • J – 200 sq ft of tar paper, 200 sq ft of asphalt shingles ROOFING


 Hammer, Tape measure, Framing square, Level

 Miter saw, Drill machinery, Screwdriver, Sander

 Safety Gloves, Safety Glasses


 One day




Trim---Facebook-BoxMake 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 our YouTube channel! See how you can Support  Me with no extra costs to you. Trim---Facebook-Box-Down



Building a 12×20 lean to shed roof

Building the rafters

Building the rafters

The first step of the lean to roof project, you need to build the rafters from 2×6 lumber. Therefore, mark the cut lines on the beams and then get the job done with a saw. Make sure you take accurate measurements, otherwise the rafters won’t fit into place tightly.



Fit the rafters to the top of the shed. Place the rafters equally spaced, every 24″ center. Use rafter ties to lock the rafters into place tightly.

Roof sheets

Roof sheets

Fit the 3/4″ plywood sheets to the roof of the lean to shed. Align the edges with attention and insert 1 5/8″ screws, every 8″ along the rafters. Make sure you leave no gaps between the sheets.

Fitting the roof trims

Fitting the roof trims

Fit 2×8 trims to the sides of the roof. Lock them into place with 3 1/2″ screws. Fit the 2×8 trims to the front and back of the roof. Insert 3 1/2″ screws to lock the trims into place tightly.

Fitting the roofing

Fitting the roofing

Cover the roof with tar paper and then install the asphalt shingles. Make sure you also install the appropriate drip edges, so you can seal the shed roof. Read the manufacturer’s instructions for a tight fit.


12x20 Lean to shed Plans - back view

12×20 Lean to shed Plans – back view

Make sure you take a look over PART 1 and PART 3 of the project, so you learn how to build the frame of the shed and how to attach the trims.

12x20 Lean to shed Plans - front view

12×20 Lean to shed Plans – front view

This shed is easy to build, sturdy and it has a nice design. The lean to design will add charm to the property and it is super sturdy.



This woodworking project was about 12×20 lean to shed roof 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.


Previous Next





You may also like

Leave a Comment