Measurements and Materials

• 1
  Save time and money by measuring correctly.measuring tape image by Horticulture from Fotolia.com
  
  Measure the distance between your shed's floor and the outside ground. For every one inch of height you will want at least four inches of length. If your shed is two feet above the ground you will want a ramp eight feet long.
  
  
• 2). Determine the width of your ramp. A four-foot wide ramp will require four joists set at 16 inches on center. To determine the number of joists required, divide the width by 16 and add one to your answer.
  
  
• 3). Figure out the amount of treated 2-by-6 lumber needed for decking. The actual width of a 2-by-6 is 5.5 inches. Leaving a one-inch gap between the decking boards, two boards laid perpendicularly across the ramp joists will cover one foot of its length. For example, an eight-foot ramp requires 16 2-by-6 boards.
  
  
• 4). To determine the amount of treated 2-by-6 lumber required for the ramp, add the number of joists and decking boards plus an additional treated 2-by-6 for the base of the ramp.
  
  
• 5). Get the most out of your lumber. You can cut from a single eight-foot 2-by-6 two decking boards for a four-foot-wide ramp. Buy lumber at lengths you can get more than one cut from. This will lower the amount of waste and the cost of materials.
  
  

Prepare Your Work Area

• 1). Remove any obstruction from beneath the shed opening (where you will install the ramp). Remove any trim from underneath the door so your framing will tie directly to the building and not to a superficial piece of material.
  
  
• 2). On the outside of the shed, mark a line 1.5 inches below your shed floor. The tops of your joists will connect to the shed at this point. Dropping the joists this distance will allow your decking to come flush with the shed floor and make a smooth transition.
  
  
• 3). Mark the layout for your joists on the shed. Draw a vertical line to represent the edge of each joist. Space the middle joists no farther than 16 inches on center.
  
  
• 4). Prepare the landing for your ramp. You'll want the ramp to come flush with the ground, so dig and level an area for the base. You can make the area larger than necessary and fill it in with dirt or concrete after you finish building the ramp.
  
  

Cut and Install Joists

• 1). Cut your joists to length with a 15-degree angle of cut. Use your framing square to get this angle. Cut the top and bottom of your ramp with the same angle. To get the correct length, measure from the long point of the angle to the short point.
  
  
• 2). Attach the joists to the shed using the joist hangers. Nail the joist hangers to the shed. Set each joist in the slot and put nails through the pre-drilled holes, attaching the board to the shed and joist hanger.
  
  
• 3). Cut and nail a 2-by-6 to the joists at the lower end of the ramp. This board will allow you to square and level the base of the ramp all at once.
  
  
• 4). On the inside of the framing, at the base of the ramp, drive stakes into the ground. Nail the joists into the stakes to hold the ramp in place.
  
  

Decking

• 1). Starting at the top, place the first board tight against the shed. Put two nails through the board into each of the joists.
  
  
• 2). Lay the boards out across the joists. You can space the boards or butt them together tightly: It won't make a difference in the strength of the ramp. Space the boards to avoid cutting the last piece to a smaller dimension.
  
  
• 3). Nail all the boards down, and pack in dirt, rock or cement at the base of the ramp.