Pier and Block foundation was chosen for the shed since it's an uninsulated structure which needs to work in a variety of climates. Piers prevent the structure from lifting out during heavy winds, while the blocks carry the load. The depth of the piers is vary based on the frost depth location the shed will be built in, which may increase the budget.
Check your local zoning regulations for Setback Requirements. Find the minimum distance from your property line and other structures before deciding on a location.
To avoid major excavation, find a location which is fairly level. You can do this easily by using a String Line tied between two stakes with a String Line Level attached to the string to gauge slope.
Solar south will vary based on your location. Sun Surveyor is a great app for smart phones that can help you determine where solar south is and how much shade a location will get on winter solstice. The shed is designed so the side to the left of the doors faces south. This is so one side of the roof can be used for solar, and the other for rainwater collection.
Use Marking Chalk Spray Paint and a Tape Measure to roughly mark the locations of the piers. Press Stakes into marked corners, then measure from corner to corner and adjust the stakes until all the measurements are correct. When you're finished, pound the stakes several inches in with a Hammer to keep them from moving.
Use the String Line to connect the stakes to make a rectangle. Measure out 12 inches from the string and mark several points then use the marking spray paint to connect the points to create a box.
Carefully choose a location for a soil pile and sod pile that's at least 9 feet out of the way (you'll need that space for ladders to do roofing later).
Use the Shovel(s) and Wheel Barrow to remove any grass, shrubs or debris from the top layer of the marked out box.
Attach String Line Levels to the strings on all four sides. Level starting roughly an inch above the ground at the highest point. Use this as a guide to remove top soil until the ground is leveled. Tamp the soil with a Tamper.
We built on an incline, and ended up with a soil ledge on one side, and had to build a retaining wall to avoid erosion. We also dug a trench for a french drain is on the inside of the retaining wall and filled it with crushed stone. This increased our build time, and building on an incline is not recommended for that reason.
Rent an 8-12" Auger and use the Digging Bar and Small Post Hole Digger if you have rocky soil.
Dig out the bottom of the hole so it flares to create a footing. This helps resist frost heave and lift from strong winds.
The depth will need to change based on the region you build in. Correct the frost depth based on your local code.
Add about an inch of All Purpose Gravel to the bottom of every hole.
In retrospect we should have added rebar into the footings for additional strength. This will be fixed in a future version.
Cut the Concrete Tube Forms to size using a Hand Saw.
Attach 3.5 Exterior Nails to the sides of the Cardboard Concrete Form Tubes to the center of a 2x4 cut to 2 feet. The tube should hang about 12 inches up from the bottom of the footing.
Make sure to wear a N95 Dust Mask to avoid breathing in concrete dust, and Cleaning Gloves to protect your skin for this next step.
Slowly pour Water over 1 Bag of Concrete in the Wheel Barrow. Mix the contents using the Garden Hoe and add water gradually until you have a thick consistency.
Shovel the concrete into the forms and occasionally insert the Margin Trowel into the concrete to remove any air pockets.
Once full, smooth out the top of the form with the Margin Trowel. Then insert a Galvanized Post Base into the form, squaring it up with the other corners, centering it with where the post should be.
Wait a day and remove the Cardboard Concrete Form Tubes from around the piers. Backfill with Compactable Fill and tamp using the Digging Bar.
To safely cut lumber, create 2 sawhorses using 45 2x4x8s cut into eight 3 foot sections and inserted into 4 Sawhorse Brackets. Always wear Work Gloves and Safety Glasses when using electrically powered equipment.
Mark the Treated 4x4x8s to size using a Carpenter's Pencil and Square then cut using a Battery Powered Hand-held Circular Saw and insert them into the Galvanized Post Bases. Drill the bolt holes out using a Battery Powered Drill and a 1/2" diameter 6" long brad point bit. Insert the 1/2" x 6" Galvanized Carriage Bolts and tighten the 1/2" Galvanized Washers and 1/2" Galvanized Nuts with a 1/2" Socket Wrench.
Treated wood can’t be composted or burned because of its toxicity and must be thrown away.
We’re open to alternatives to improve this design.
Place 2 Treated 2x6x12s and 2 Treated 2x6x16s as end plates on Concrete Deck Blocks and use Shims and a 4' Level to level them until they all line up with each other at the corners.
Drill the holes for the bolts and bolt the 4x4s to the end plates like you did the piers.
Mark the longer end plates for the floor joists.
Cut the remaining 2x6x12s to 11' 9" to use as floor joists.
Roughly place the Concrete Blocks in place by inserting the floor joists into them, and aligning the joists roughly with the marks.
After each board is lined up, remove an inch of soil under each block and add All Purpose Gravel under each block until the joists are level with the side beams.
Carefully mark the unattached floor joists with numbers using a Carpenter's Pencil so you can place them back in the same place later. Then remove them for the next step.
Use the Shovel and the Hoe to spread a layer of #57 Drainage Gravel around the blocks to improve drainage.
Insert the floor joists back into place using your marks.
Hammer 2 3.5" Exterior Nails into each end of each joist.
| Placement | Technique | Nail Size | Nail Frequency / Number | Occurances | 3.5" Nails |
|---|---|---|---|---|---|
| End Plate | End Nail | 3.5" | 2 nails | 26 | 60 |
Load the Battery Powered Nail Gun with 2.5" Interior Nails.
Lay 5/8" (19/32) Plywood down on top of the joists end to end, nailing the corners as you go. IRC TABLE R503.1
Plywood should be run so the direction of the grain runs perpendicular to the joists to increase strength.
Once in place Mark a Chalk Line across the plywood for each joist using the nails on either end as a guide for nailing.
Nail the plywood in using the following nailing schedule:
| Placement | Nail Size | Nail Frequency / Number | Occurances | Nails / Sheet | 2.5" Nails |
|---|---|---|---|---|---|
| Edges on Studs | 2 or 2.5" | Every 6" on center | 6 sheets | 48 | 288 |
| Center on Studs | 2 or 2.5" | Every 12" on center | 6 sheets | 16 | 96 |
| Total | 384 |
Place Bricks on Tarp
| Item | Cost |
|---|---|
| 100' String Line | 2.98 |
| 4 String Line Levels | 5.86 |
| Solar Surveyor App | 10 |
| Marking Spray Paint | 5.27 |
| 25'+ Tape Measure | 9.88 |
| 4 2-ft Wooden Stakes | 4.97 |
| Hammer | 4.98 |
| Digging Shovel | 5.98 |
| Wheel Barrow | 49.97 |
| Tamper | 26.98 |
| 8" Auger Rental | 50.00 |
| Digging Bar | 31.97 |
| Small Post Hole Digger | 24.97 |
| Hand Saw | 9.94 |
| 2 N95 Dust Masks | 7.47 |
| Cleaning Gloves | 1.98 |
| Hoe | 15.97 |
| Margin Trowel | 5.77 |
| Carpenter's Pencil Set | 3.49 |
| Speed Square | 7.67 |
| 2 Sawhorse Brackets Sets | 13.94 |
| Work Gloves | 9.99 |
| Safety Glasses | 12.99 |
| Battery Powered 7-1/4-in Hand-held Circular Saw | 279.00 |
| Battery Powered Drill | 159.00 |
| 1/2" diameter 6" long brad point bit | 9.97 |
| 1/4" Drive SAE Socket Wrench Set | 29.97 |
| 4' Level | 14.97 |
| Battery Powered Nail Gun | 399.00 |
| Plumb Chalk Line | 5.97 |
| Total | 1,220.90 |
| Item | Use | # | Cost | Total |
|---|---|---|---|---|
| All Purpose Gravel 50 lb Bag | Piers, Blocks | 6 | 4.70 | 28.2 |
| 1/2" x 2' Rebar (varies) | Piers | 4 | 2.47 | 19.46 |
| 1 lb pack of 3.5" Exterior Nails | Joists | 2 | 4.27 | 9.94 |
| 8"x4' Concrete Tube Forms (varies) | Piers | 2 | 9.50 | 19.00 |
| 2x4x8 | Piers | 1 | 3.13 | |
| 5-Gallon Water Jugs | 3 | 19.99 | 59.97 | |
| Concrete 80 lb bags (varies ) | Piers | 8 | 5.97 | 47.76 |
| 4" x 4" Galvanized Post Base | Piers | 4 | 11.37 | 45.48 |
| Cubic Yards of Compactable Fill | Piers | .25 | 9.42 | |
| Treated 4x4x8 | Piers | 1 | 8.32 | |
| 1/2" x 6" Galvanized Carriage Bolts | Piers, Joists | 16 | 2.53 | 40.48 |
| 1/2" Galvanized Washers | Piers, Joists | 16 | 0.24 | 5.28 |
| 1/2" Galvanized Nuts | Piers, Joists | 16 | 0.38 | 6.08 |
| Treated 2x6x12 | Joists | 14 | 9.45 | 124.32 |
| Treated 2x6x16 | Joists | 2 | 12.42 | 23.14 |
| Concrete Deck Blocks | 28 | 9.60 | 193.20 | |
| Pack of Shims | Deck Blocks | 1 | 4.95 | |
| Cubic Yard of #57 Drainage Gravel | Drainage | 1 | 29.00 | |
| 2.5" Interior Nails for your Nail Gun | Sheathing | 384 | ||
| Total in Pack | 2000 | 38.7 | ||
| Remaining | 1616 | |||
| 4x8 5/8" (19/32) Plywood | Sheathing | 7 | 19.57 | 136.99 |
| Bricks | Cover | 12 | .69 | 8.28 |
| 20' x 30' Heavy Duty Tarp | Cover | 1 | 89.98 | |
| Total | 951.08 |
Materials noted as "(varies)" depends on the frost depth for your location.