The following drawings:
The plans have a List of Materials, which includes size and quantities for:
The Instructions include the following topics:
There are three kinds of foundations that are practical for this type of shed—a concrete slab on grade, a concrete block on a concrete strip footing or a wooden floor supported on pressure treated 6x6s. The easiest and most mobile is the wood foundation. Once concrete is poured it is permanent.
Note:These plans are for a storage shed that is 12' wide and 16' long, but its length is totally up to you. If you need a shed that is longer than the side elevation, just add more studs and trusses and revise the foundation and floor accordingly. For sheds longer than 16' add a 2x4 collar tie to the truss every 8'.
See the foundation drawing. Place the anchor bolts on 4 foot centers or less around the outside perimeter. Make sure they are in the center of the 2x4 when placed flush on the edge and are at least 2" high. These bolts are usually placed after the concrete is poured, but before it hardens. Depending on where you live and how cold the winters are, the perimeter of the slab should be built up in thickness, 12" being the minimum thickness and 12" in from the edge as well. Typical with any concrete slab or footing, make sure all top soil is removed and provide a base of well compacted sand, gravel or undisturbed non-organic soil under it.
To support a row of concrete blocks, you need a concrete footing. The blocks are 8x8x16" long. The footing is 6" thick by 16" wide, poured over well compacted gravel. The forms are made of 2x6s on each side nailed on the top with 1x3 cleats and fastened on the side with 1x3 pegs. After leveling the concrete, scratch out a key for the blocks to make a good bond with the mortar and concrete. The next day, at least, after pouring the footing plate onto the top of the blocks, running their length. The box and floor joists are nailed onto this plate.
See the foundation drawing. The wood floor is typically 5/8" tongue and groove plywood on 2x6s at 16" centers on 6x6s, pressure treated to last for 40 years. Put these 6x6s on a bed of about 6" deep compacted gravel to help in drainage. Make sure the center one is level and true with the edge ones. The 6x6s are 16' long and placed 12' apart to the outside with a center 6x6 to support the mid span of the floor joists. Cut 2 - 2x6s 16'-0" and lay them both out together for the box joists. Start at the left end, measure 15 1/4" and place a mark with an X on the right of the mark. Now move the tape to this mark and continue to mark and place an X in the same manner at every 16" mark on your tape, until you run off the 2x6. Cut the 13 - 12 foot 2x6s to 11'-9" to allow for the combined 3" for the box joists on each end, as shown in the above drawing.
When you nail the joists onto this box joist the left edge of the joist will be on the mark covering up the X. After nailing on all the joists you should be able to place your tape on the edge of any joist, except the first one, and read a multiple of 16". This will enable the plywood to end on the center of the joist. When the joists are all nailed on, measure their diagonals to be sure the floor is square. Bump one 6x6 to the left or right until the diagonals are the same and the floor is square. Go ahead and nail the plywood on. When using 5/8" tongue and groove (T & G), start with the tongue flush with the outside of the floor and the groove towards the inside of the floor. Notice the stamp on the plywood, it usually says place this side down (the tongue is thicker on the bottom).
Nail on your first two sheets end to end, snug the end joints up. Just use a few nails to keep the plywood in place and mark where the joists are. Keep them back from the groove side by at least 6" to allow the next sheet to slip into the groove easier. Cut the third sheet in half - 4'x4' and start on the left, the way you laid out the joists. Place the tongue up to the existing groove get your helper to stand on the tongue and groove together while you hammer lightly with a sledge hammer against a 2x4 against the groove side of the third sheet. The sheet should slip into the groove of the one nailed on. Now install the fourth sheet (full size) next to the half sheet. Then install the other half to get to the end of the floor. This is called staggering your sheets so the joints are not in the same line the same way brick layers build a brick wall. Continue the next row with a full sheet and the last row by staggering your sheets again. Nail or screw on the plywood securely: nails spaced 6" apart on all joints and 12" apart in the middle.
After the foundation is made start on the side walls. Lay them out in place—2x4 studs 45" long, for a 4' high wall. The studs are nailed to a top and bottom plate. Each plate is a 2x4 that is 16' long. The studs are nailed on the plates at 24" centers.
Sheet the long walls while they are laying down. Make sure they are square. Stand these walls up, then nail a 16' long 2x6 onto the top plate making the inside flush and overhanging the outside by 2". This 2x6 acts like a strongback to strengthen the wall and keep it from bowing out from weight on the roof as well as forming an overhang for the roof.
Next layout the trusses, full size on the floor. Layout from the measurement on the Truss Layout drawing. Snap a line for the roof where it sits on the 2x6. This line should be longer than 12' - 4". Label it line #1.
Snap another line, #2, up 32 7/8" and parallel to line #1. Mark in the center of this layout a point up 15 1/8" from line #2. Square a line down from this point to the bottom line. This is the center line of the truss.
From the center line measure 44 1/2" along line #2 each way out from center, and mark these points. From the center line and along line #1 in both directions mark points at 6' - 2". Connect these three points on each side of the center line. This is the outside line of the truss. Are the measurements of the 2x4s close to mine on the plan? They should be 47" and 44".
Now cut these 2x4s to length using your layout as a guide to mark the correct angles.
You'll notice that the top roof has a 4/12 pitch, so the plumb cut for that 2x4 is 4/12 on your square or 18.5 degrees for a cut off saw. Also, the lower part of the roof has an angle cut of 41 1/2 degrees with the horizontal. The joint between the two is an equal miter that should be 15 degrees. Be accurate, when you're happy with the joints by checking them on the full size layout, mark the two pieces as a pattern (pat) and mark the remaining 2x4s using the pattern. Cut a total of 26 pieces each.
Make your gussets from 1/2" plywood (don't use OSB, K-3 particle board or multicores). Cut them 12" long with the grain running length ways. Nail each side of the gusset with 8 - 2" galvanized nails, spreading them out and making sure the joints of the 2x4s are tight. Glue isn't required here—there's too much expanding and contracting due to temperature changes.
Make 9 trusses with the gussets nailed to both sides of each truss. Make two more trusses with the gussets nailed to one side only. These are the gable trusses—gussets on the inside of the building. Make two more trusses to trim the overhang. The gussets on the overhang should be only on the inside and should be trimmed flush on both edges of the 2x4.
Now brace up the two outside walls so they are plumb and straight. Notice the Side Elevation drawing and the layout of the trusses to enable the plywood or OSB ends to rest on the center of the trusses.
On the top of the walls layout the trusses as shown on this drawing. Extend your tape out 6" from the end of the wall and mark a point at 23 1/4". Place an "X" next to this point so that this point represents the edge of the truss and the truss sits on top of the X, centered on 24". From this point continue marking points along the wall at 24" and an X where the truss will sit. The X's should be on the same side of all the points. Remember to put a gable truss flush with the outside of the wall at each end (with the gussets facing the inside of the building). The sheeting will eventually come up the wall and be nailed onto the truss, front and back.
To hold the trusses in place before you sheet the roof, nail a 1x4 along the trusses near the ridge to tie them together. This is where a friend comes in handy to give you a hand. Leave the two overhang (trim) trusses on the ground for now.
To hold that first awkward truss up, brace it temporarily either to a stake pounded into the ground or to the inside of a wall. Nail the bottom of the truss securely into the 2x6 with 3" nails. When all the trusses are up and tied together with a 1x4 near the ridge and braced up nice and plumb go have a coffee.
Now let's finish off the back wall. With the trusses forming the shape of the roof, just nail studs to the underside of the truss to a plate nailed on the floor. If the shed is not going to be insulated, place these 2x4s on the flat. If insulated place them on edge in the wall. They should be placed at 2' centers and kept flush with the outside of the truss. Lay the studs out from the center so that when the sheeting is put on there will be a 12" strip of sheeting on each side of two sheets. Refer to the Back Side Framing Elevation drawing.
On the front end lay out the door jamb, keep it plumb and use straight 2x4s. The header over the door should be at 6' - 8" clearance. Make the header long enough so you can nail each end of it to the inside edge and bottom of the truss. It's best to put the header board up and mark its ends along the actual sides of the truss so you are sure to get an exact fit. Refer to the Front Side Framing Elevation drawing.
Apply the wall sheathing when the framing is complete. The wall sheathing should go over the trusses as well. Nail it well to the truss and to the header, especially around the joints. This is why you didn't put gussets on the outside of the truss, the sheathing takes their place. Make sure the sheeting is trimmed off nicely at the top of the trusses so it won't interfere with the roof sheeting.
Start ripping the roof sheathing to the measurements required. Start at the bottom, allow an extra 1" for the first row of sheeting to overhang the truss where it sits on top of the 2x6. It isn't necesary to miter the joints in sheathing, butt joints are good. Keep the sheets separate from each other the thickness of a 3" nail to allow for expansion (about 1/8").
Nail up the sheathing at about 12" center in the middle of the sheets and about 6" centers along the ends. Get your friend to help you again by holding up the overhang trusses flush with the end of the roof sheathing, forming a 6" overhang, with the gussets on the inside.
Now nail the 1x6 trim on the ends of the trusses at the front and back sides, flush with the top of the roof sheathing.
Install your choice of roofing. I prefer fibreglass/asphalt laminated shingles. Usually the manufacturer has very explicit instructions included with their shingles.
Nail the 1x4 trim on around the door.
Nail a 1x4 on the inside of the latch-side jamb (the side opposite the jamb the door is hinged to). Offset the 1x4 so it extends about 3/4" out from the door-opening edge of the 2x4 (all along the length of the 2x4). This makes a door stop on the latch side of the door so the door can be securely latched close.
The door can be made of a framework of 2x4s on the flat and sheathed with OSB, to match the walls, as shown in the Front Elevation drawing. Nail 1x4 trim over the sheathing in the same locations as the 2x4s.
Attach the door to the frame with 3" galvanized strap hinges screwed to the door trim and jamb trim with 2 1/4" x # 8 screws. Drill holes through the trim to prevent splitting, especially at the top and bottom.
For security, I'd recommend a 6" hasp and padlock or heavy duty padbolt (barrel bolt that accepts a padlock).
The Materials List includes 1x4 trim for the corners and over the vertical joints of the plywood or OSB sheeting, as shown on the coloured drawing. When installing the corner boards, rip down the side corner less 3/4" so the overall width when nailed on will equal 3 1/2". Nail the side trim corner on first, then overlap the front trim corner.
Build a little ramp to the door to wheel the mower in and you are all set.
Enjoy your new shed!
Dave(Ask Dave) (About Dave)
Hi, I'm Dave Osborne. With over 50 years experience as a journeyman carpenter, foreman and contractor in heavy construction I enjoyed working with apprentices and sharing the tricks of the trade that others shared with me. Now I get emails from Members all over the world and we include many of my answers in our Free Monthly Newsletters. Some of my answers include drawings and instructions specific to a project, but may also answer your questions. I use correct construction terminology, so you can confidently inform your building supply dealers or contractors exactly what you need.
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