A riding lawnmower is a significant investment that needs more than a canvas cover as protection from the elements. While you can purchase a purpose-built shed or convert a garden shed to store a lawnmower, it is cheaper to build your own shed that you can customize to suit the location and the size of your machine. Most riding lawnmowers fit through a 4-foot opening. Recycled products or scrap material such as shipping pallets and surplus lumber from a renovation or demolition project can reduce the cost of the project. Check warehouses, industrial areas and construction sites for discarded pallets.
Building the Floor
Place four pallets touching each other to form an 8-foot-by-8-foot square. Mark the four corners of each pallet on the ground with chalk powder or flour. Remove one pallet to get to the inside corners of the other pallets. These will be the positions for placement of footings made of cinder blocks.
Dig rectangular holes at each corner of the pallets. These holes should be slightly bigger than the cinder blocks and to a depth of about half the cinder block's height. The corners where two pallets meet will have one cinder block supporting both corners of the pallet. Level the bottom soil and tamp it down using one of the cinder blocks as a tamper.
Place one cinder block in each hole. Wrap a string around the block at one corner of the square and stretch it on the outside to the next corner block. Wrap it round this block and stretch the string on to the next corner block. Repeat this procedure until you reach the first block. The string should now form an 8-by-8 foot square. Use the string as a guide to align the cinder blocks.
Place an 8-foot-long piece of lumber or any similar straight edge on top of two corner cinder blocks on one side of the square. Place a spirit level on the lumber to check that the blocks are level. Repeat this procedure for all four sides and the blocks inside the square. You may have to dig some of the holes deeper or add soil to get all the blocks level.
Replace the four pallets on top of the cinder blocks. Each corner should be fully supported by the blocks. Screw the pallets together where they touch each other. Lug bolts through the edge stringers make better anchors.
Screw two 4-foot-by-8-foot OSB sheets over the top of the pallets to form a more secure floor.
Building the Walls
Place two pallets on edge along the rear edge of the floor to form the back side of the shed wall but at half height. Screw the pallets to the floor and to each other. Repeat for the left and right sides of the shed. The pallets should be placed with the slats in a vertical position. Screw the pallets of the rear half wall to the left and right side half walls.
Split a pallet in half vertically with a circular saw. Place one half on the left side front edge of the shed flooring and screw the pallet into place. Repeat on the right side. This will leave a 4-foot-wide opening for the door. Screw both half pallets to the left and right sides half walls.
Cut the top side of a pallet in half horizontally with a circular saw. Cut across the slats and level with the lower edge of the center support stringer. Remove the lower edge support stringer but leave the slats on the rear side of the pallet at their full length. Measure down 1 foot from the top of the pallet (the side with slats on both sides of the pallet). Draw a line parallel to the top edge and cut the pallet along this line. The pallet will now be a total height of 3 feet with only 1 foot of it double sided. Repeat with a second pallet. These two pallets will form the upper portion of the rear wall of the shed.
Place one of the cut down pallets on top of the rear half wall with the longer slats overlapping the outside of the half wall and the center support stringer resting on the top edge of the half wall. Align the pallet with one edge of the rear wall. Screw the longer slats into the half wall. Repeat with the other cut down pallet but align it with the other edge of the rear wall. Screw these two pallets together.
Cut the top side of another pallet in half horizontally across the slats in line with the lower edge of the center support stringer as in Step 3. Remove the lower edge support stringer but leave the rear side pallet slats their full length, again as in Step 3. Repeat with a second pallet. Place both pallets on a flat surface, side by side with the longer slats on the bottom and with the top and bottom edges perfectly aligned. Clamp the two pallets together. Mark a point 1 foot down from the right top edge. This will be the rear left side of the upper portion of the wall. Draw a line from this point to the left top edge. Use a straight edge like an 8 foot length of 2-by-4 inches lumber to draw a straight line angling up from the rear to the front. Cut the pallets along this line.
Place the cut pallet with the smallest side on top of the left half wall where it meets the rear upper wall. Screw the long slats of the pallet into the half wall and screw the rear edge into the rear wall, as in Step 4. Place the other pallet on top of the front portion of the half wall and screw the slats into the wall. Screw both the pallets together. Repeat steps 5 and 6 for the other side of the shed.
Place a 8-foot length of 2-by-4 inch lumber flat-side down on top of the half pallets that form the front of the shed. Cut a pallet horizontally in half. Place the half pallets on top of the 2-by-4 inch lumber and screw them into place. Screw the pallets to the side walls.
Screw slats removed from spare or damaged pallets to fill the gaps between the slats on the outside of the shed.
Split a pallet in two vertically. Attach each piece to each side of the door gap using heavy-duty hinges such as garden gate hardware. Add a latch where the pallet doors meet.
Building the Roof and Ramp
Screw four 8-foot lengths of 2-by-4 inch lumber across top of the side walls, evenly spaced, to support the roof.
Place four pallets on the 2-by-4 lumber and screw them into the lumber as well as the top of the walls to form the roof. Cover the roof pallets with tar paper and staple the tar paper into place.
Screw slats from a spare or damaged pallet all around the edge of the roof to give the roof a clean line.
Screw a pallet level with the rim of the door opening for the ramp. Bury the opposite edge in the soil so that this end is level with the ground. Alternatively, use soil from the holes you dug for the cinder blocks and some gravel to build up an earth ramp to the door. Screw two lengths of 6 foot foot long 2-by-6 inches lumber on edge to the door rim on either side of the door opening to contain the soil for the ramp.
Painting or staining the shed will protect the wood from the weather and also give the shed a more pleasing appearance.
Discarded garage door sections can be used for the walls instead of pallets but will require vertical 2-by-4 inches lengths of lumber to support them from the outside
Instead of pallets, you can use corrugated iron or polycarbonate sheets for the roof. They can also be used for walls but will need to be screwed to 8 feet by 8 feet frames made of 2-by-4 inch lumber.
Plywood can be used as flooring, but OSB is cheaper.
Things You'll Need
30 wood shipping pallets, reversible type
Chalk powder or flour
10 concrete cinder blocks
String, 40 feet or longer
Construction screws, box of 250 pieces
Screwdriver or power drill/driver
8 lug bolts (optional)
2 OSB sheets, 4 feet by 8 feet
2-by-4 inch lumber, 5 pieces each 8 feet long
4 heavy-duty hinges
Avoid full size 8 feet by 8 feet metal doors as they are not only more cumbersome to handle but you will also need to cut two at an angle for the side walls.
Use only reversible, or two-sided, pallets that have stringers even in the middle rather than just support blocks. These pallets are used to ship heavy items such as construction bricks or stones.
Plastic pallets won’t work as well as wood pallets because they don’t hold screws as well. You would need to use lug bolts which would increase the cost of the shed.