Y
Published on

DIY Shed

Authors
  • avatar
    Name
    Yinhuan Yuan
    Twitter

Designing a concrete pier foundation for a 16 ft by 24 ft shed requires consideration of Ontario’s building codes, frost line depths, and load distribution. Here's a recommended layout:

1. General Considerations for Southern Ontario

  • Frost Line Depth: In Southern Ontario, piers must be dug at least 4 feet below ground to prevent frost heaving.
  • Spacing of Piers: Typically, piers should be spaced 6–8 feet apart, depending on the load.
  • Beam and Joist Support: The piers should support beams, which in turn hold the floor joists.
  • Weight Distribution: Ensure the load of the shed is evenly distributed across all piers.

2. Suggested Layout

For a 16 ft by 24 ft shed, you’ll need 9 concrete piers, arranged in a 3x3 grid.

Pier Placement

  • Place piers at corners, midpoints, and center for even load distribution.
  • The spacing will be approximately:
    • 8 feet apart along the 24-ft side (long side).
    • 8 feet apart along the 16-ft side (short side).

Diagram

Here's the layout:

O---------O---------O (16 ft wide)
|         |         |
|         |         | (8 ft spacing)
O---------O---------O
|         |         |
|         |         |
O---------O---------O (24 ft long)
  • O = Concrete pier location.

3. Materials and Dimensions

Concrete Piers:

  • Use sonotubes (12-inch diameter) for the piers.
  • Depth: Minimum 4 ft below grade to reach below the frost line.

Beams and Joists:

  • Beams: Use 2x8 or 2x10 pressure-treated lumber.
  • Floor Joists: Use 2x6 or 2x8, spaced at 16 inches on center.
  • Joist Hangers: Attach joists to the beams using metal hangers for added stability.

Anchoring System:

  • Insert J-bolts into the concrete piers to secure the beams.
  • Use adjustable post bases for leveling.

4. Construction Steps

  1. Mark and Dig Holes:

    • Mark the pier locations based on the layout.
    • Dig holes at least 12 inches wide and 4 feet deep.

  2. Install Sonotubes:

    • Place sonotubes into the holes and fill them with concrete.
    • Insert J-bolts into the wet concrete to anchor the beams.

  3. Level the Piers:

    • Ensure all piers are level before the concrete sets.

  4. Install Beams:

    • Lay beams across the piers and secure them with the anchors.

  5. Attach Joists:

    • Attach the floor joists perpendicular to the beams using joist hangers.
    • Add blocking between joists for extra stability.

  6. Install Flooring:

    • Lay down 3/4-inch tongue-and-groove plywood or similar material for the shed floor.

5. Ontario Building Code Considerations

  • Permit: Check with your local municipality to determine if a building permit is required.
  • Inspections: The foundation may need to be inspected before proceeding with the construction.
  • Load Requirements: Ensure the design can support the expected weight, including snow loads.

Would you like detailed instructions for any specific step or recommendations on materials?

Detailed Instructions for Building a 16 ft x 24 ft Shed with a Concrete Pier Foundation in Southern Ontario

1. Planning and Preparation

Tools and Materials Needed

  • Tools:

    • Measuring tape
    • Chalk line or string line
    • Shovel or post hole digger
    • Level
    • Drill with concrete bits
    • Circular saw
    • Joist hanger nails/screws
    • Hammer
    • Power auger (optional for digging holes)

  • Materials:

    • Sonotubes (12-inch diameter)
    • Concrete mix (pre-mixed or components to mix on-site)
    • J-bolts or adjustable post anchors
    • Pressure-treated lumber for beams (2x8 or 2x10) and joists (2x6 or 2x8)
    • Metal joist hangers
    • Galvanized nails or screws
    • Gravel (for base under piers)
    • 3/4-inch plywood or OSB for flooring
    • Wood preservative (for untreated cuts)

2. Marking the Foundation Layout

Steps:

  1. Measure and Mark Corners:

    • Use measuring tape to mark the four corners of the 16 ft x 24 ft area.
    • Ensure corners are square using the 3-4-5 triangle method or a framing square.

  2. Mark Pier Locations:

    • Divide the layout into a 3x3 grid, placing piers at:
      • Four corners.
      • Two along each long side (midpoints).
      • One at the center of the structure.

  3. Check Alignment:

    • Use a string line or chalk line to connect the pier locations.
    • Measure diagonals to confirm the layout is square.

3. Digging Holes for Piers

Steps:

  1. Dig Holes:

    • Use a shovel or power auger to dig 9 holes, each at least:
      • 4 feet deep (below frost line in Southern Ontario).
      • 12 inches wide (or the diameter of your sonotubes).

  2. Add Gravel Base:

    • Place 4-6 inches of gravel at the bottom of each hole for drainage and stability.

  3. Install Sonotubes:

    • Place a sonotube in each hole, ensuring it extends above ground level by at least 6-12 inches.
    • Use a level to ensure the sonotubes are vertically aligned.

4. Pouring the Concrete

Steps:

  1. Prepare Concrete:

    • Mix concrete according to package instructions or use pre-mixed bags.
    • For extra strength, use a high-strength mix.

  2. Fill Sonotubes:

    • Pour concrete into the sonotubes, tapping the sides to remove air bubbles.

  3. Insert Anchors:

    • While the concrete is still wet, insert J-bolts or adjustable post anchors at the center of each pier.
    • Ensure the anchors are aligned and at the correct height.

  4. Let Cure:

    • Allow the concrete to cure for at least 24-48 hours before proceeding.

5. Installing Beams

Steps:

  1. Attach Beams to Anchors:

    • Place pressure-treated beams (e.g., 2x8 or 2x10) on top of the piers.
    • Secure beams to the anchors using bolts or screws.

  2. Check Level:

    • Use a long level or laser level to ensure all beams are level. Shim where necessary.

  3. Secure Beam Ends:

    • At corners and intersections, secure beams using galvanized brackets or bolts.

6. Installing Floor Joists

Steps:

  1. Mark Joist Positions:

    • Mark joist positions on the beams every 16 inches on center (standard spacing).

  2. Attach Joists:

    • Use metal joist hangers to secure each joist perpendicular to the beams.
    • Ensure joists are flush and level with the top of the beams.

  3. Install Blocking:

    • Add blocking between joists at mid-span for added strength and to prevent twisting.

7. Installing the Shed Floor

Steps:

  1. Lay Plywood Sheets:

    • Use 3/4-inch tongue-and-groove plywood or OSB for the shed floor.
    • Lay sheets perpendicular to the joists, ensuring edges are supported by joists.

  2. Fasten Flooring:

    • Secure the flooring using screws or nails every 6-8 inches along the edges and 12 inches in the middle.

  3. Seal and Protect:

    • Apply a wood preservative or waterproofing sealant to the floor to protect against moisture.

8. Final Inspections

  • Check Stability: Ensure the structure is level and all components are securely fastened.
  • Verify with Local Code: Consult your municipality for inspections if required by Ontario Building Code.

Tips for Success

  1. Check Weather: Avoid pouring concrete in freezing conditions unless using additives.
  2. Use Pressure-Treated Lumber: All beams and joists should be pressure-treated for outdoor use.
  3. Prepare for Future Expansion: If you plan to upgrade your shed (e.g., add heavy equipment), consider reinforcing the foundation further.

Would you like assistance designing the roof, walls, or any additional shed features?

Designing the Roof and Walls for a 16 ft x 24 ft Shed

1. Roof Design

The roof design should consider snow loads in Southern Ontario and aim for efficient drainage. Common options include gable roofs (most popular for sheds), shed roofs, or hip roofs.

Gable Roof (Recommended)

A gable roof is durable, straightforward to construct, and ideal for areas with heavy snowfall.

Key Features:

  • Sloped design for efficient water and snow drainage.
  • Provides attic storage or additional overhead space.

Steps to Construct the Roof

  1. Determine Roof Pitch:

    • Use a standard pitch of 4:12 to 6:12 (4-6 inches of rise for every 12 inches of run).
    • A steeper pitch is better for shedding snow.

  2. Build Roof Trusses:

    • Materials:
      • 2x4 or 2x6 lumber for trusses.
    • Truss Design:
      • Use pre-made trusses or build triangular trusses with gusset plates at the joints for added strength.
    • Spacing: Trusses should be spaced 24 inches on center.

  3. Install Ridge Beam and Rafters:

    • Place a ridge beam along the top center of the shed.
    • Attach rafters to the ridge beam and the wall top plates.

  4. Sheathing and Roofing Material:

    • Cover the roof with 5/8-inch OSB or plywood.
    • Install underlayment (e.g., roofing felt).
    • Add shingles, metal roofing, or another weatherproof material.

  5. Add Overhangs (Optional):

    • Extend rafters by 12-18 inches to create eaves for added weather protection.

2. Wall Design

The walls need to support the roof and provide stability. Use standard framing techniques with studs, plates, and sheathing.

Steps to Build Walls

  1. Wall Frame:

    • Use 2x4 lumber for studs and plates.
    • Build wall sections flat on the ground before raising them.

  2. Stud Spacing:

    • Space studs 16 inches on center for strength.

  3. Headers for Doors and Windows:

    • Install double 2x6 or 2x8 headers above door and window openings.

  4. Assemble the Wall Sections:

    • Nail or screw studs to the top and bottom plates.
    • Attach sheathing (e.g., 1/2-inch OSB or plywood) to the exterior.

  5. Raise and Secure Walls:

    • Lift wall sections into place and secure them to the floor joists.
    • Use temporary bracing to hold walls plumb while attaching.

3. Exterior Finishing

Siding Options:

  • Vinyl Siding: Durable and low maintenance.
  • Wood Siding: Aesthetic and natural but requires upkeep.
  • Metal Panels: Strong and weather-resistant.

Trim and Paint:

  • Install trim around doors, windows, and corners.
  • Apply weatherproof paint or stain to wood siding.

Insulation (Optional):

  • If you plan to use the shed year-round or as a workshop, insulate the walls with fiberglass batts or foam panels.

4. Doors and Windows

  • Door Options:
    • Standard hinged doors.
    • Sliding barn-style doors for larger equipment.
  • Window Placement:
    • Install at least 2-3 windows for ventilation and natural light.

5. Additional Features

  • Ventilation:
    • Add roof vents or a ridge vent to prevent moisture buildup.
  • Gutters and Downspouts:
    • Install gutters to channel rainwater away from the shed.
  • Electrical Wiring (Optional):
    • If needed, install wiring before finishing the interior walls. Consult a licensed electrician for code compliance.

Materials List for Roof and Walls

Lumber:

  • 2x4s for studs, plates, and rafters.
  • 2x6s for headers and trusses.

Sheathing and Roofing:

  • 5/8-inch OSB or plywood for walls and roof.
  • Roofing felt or underlayment.
  • Shingles or metal roofing.

Other Materials:

  • Nails, screws, and gusset plates.
  • Exterior siding.
  • Trim, paint, or stain.

Would you like a detailed cut list, a step-by-step visual guide, or assistance with any specific aspect of the design?

Discuss on Twitter • View on GitHub