A lean-to shed is a great way to add storage to your property with a minimum of supplies and effort. This project is easy enough that even people with only modest carpentry skills should be able to build a successful lean-to. You don't need fancy materials, either. A lean-to can provide storage for garden tools or outdoor furniture. In most cases, a lean-to is built to lean up against an existing structure.
Find plans for a lean-to shed that you can follow, or draw up your own plans. Lean-to construction is simple enough that you don't need especially detailed plans, but a simple plan to follow will make construction easier. Decide whether you want to try to build a stand alone, or an assisted lean-to shed. Determine in the planning stage how big your shed will be. 1.8 x 1.2 m (6 x 4 feet) is a common size for a small lean-to shed. If you find plans that you like for a smaller shed, simply scale them up to the size that you want to build. Determine the amount of material that you will need, and buy your building supplies. Conventional carpentry wisdom suggests ordering 10 per cent more material than you require.
Mark out the area where you are going to build your shed. Map out the space with stakes and string before you begin building. Build a foundation for your shed to sit on. Cement footings should be poured for a free-standing shed. A shed which is going to lean against an existing building can be placed on pressure treated skids. Concrete blocks can also be used to build a base for a shed.
Build the floor of your lean-to shed. Use pressure treated 5 x 10 cm (2 x 4) timber to construct the frame of your floor. You should build the floor with the joists on 40 cm (16 inch) centres. Cover the floor with 1.8 cm (3/4 inch) plywood.
Build the walls to your shed. Build the walls separate from the shed and then raise them into place. Like the floor, the walls should be built with basic studs on 40 cm (16 inch) centres. Build the front wall with framing for a door to be placed in the shed if a door was included in your plans. Your back wall needs to be taller than your front wall to build a typical lean-to with a pitched roof. The height differential and the mitre degree that you need to cut the top studs at will depend on the exact dimensions of the shed you are building. Raise the walls and anchor them to the floor.
Construct the roof of your lean-to. Build your roof with 5 by 10 cm (2 x 4 inch) rafters. Attach the rafters to the mitred studs if building a pitched roof. You can also build 'L" rafters to create a pitched roof with even walls. If you want a flat roof, you can attach straight rafters directly to the tops of the walls.
Finish your shed. These steps depend on what you want your shed to look like. Refer to your original plans. You can roof your shed with asphalt shingles or cover it with tin. A shed can be covered in wood, siding or tin on the outside walls. You can hang a door if you left an opening for one. Some lean-to sheds are designed to be open, with no front wall or door necessary.
Look for recycled building material to save money on your lean-to. Many do-it-yourselfers have scraps left over from projects that would work as supplies for building a lean-to.