Build a Shed Floor System

A. Finished-Project Specification

Deliverable: one shed floor platform consisting of a prepared and compacted base, leveled skids, piers, or footings at the approved spacing, a squared and blocked rim-and-joist frame secured to its supports, fastened subfloor sheathing on the approved schedule, and a completed floor inspection.

B. Assessed Floor-System Schedule (Component Schedule)

Component	Quantity	Format	Standard	Preparation / Purpose
Base preparation	1	Compacted pad or support locations	Graded and draining away from the platform	Provides stable, drained bearing for supports
Support installation	Per plan	Skids, piers, or footings	Level, spaced, and bearing per approved plan	Carries the frame at the approved elevation
Rim-and-joist frame	1	Assembled frame	Squared by diagonals, blocked per plan	Establishes the floor plane and load path
Frame anchorage	Per plan	Connectors / uplift devices	Secured to supports per approved detail	Resists lateral and uplift loads on the platform
Subfloor sheathing	Per footprint	Fastened panels	Staggered joints, approved gaps and schedule	Creates the finished walking and wall-bearing surface
Floor inspection	1	Completed checklist	Plane, square, stiffness, anchorage, drainage, edges confirmed	Authorizes handoff to Project 15 wall framing

C. Material and Resource Takeoff

• Base material: approved gravel or compacted base sufficient to cover the full footprint at the specified depth.
• Supports: skids, piers, footings, or bases matching the approved plan, spacing, and ground-contact treatment rating.
• Framing lumber: rim boards, floor joists, and blocking cut to the approved spans, grade, and treatment.
• Connectors and fasteners: approved anchorage devices, joist connectors, and fasteners matched for corrosion compatibility with the treated lumber.
• Subfloor sheathing: panels matched to the approved thickness, span rating, and fastening schedule.
• Documentation: the shed floor worksheet, support and anchor location records, and photographs required before sheathing conceals the frame.

D. Acceptance Standards

Check	Standard
Base and drainage	Site graded and draining away from the platform; base compacted before supports are set
Support installation	Skids, piers, or footings level, spaced, and bearing per the approved plan
Frame dimensions and square	Frame dimensions and diagonals match the approved layout within tolerance
Blocking and connectors	Blocking and connectors installed per the approved schedule at every required location
Anchorage	Frame secured to supports and uplift devices installed per the approved detail
Subfloor sheathing	Panels laid out with staggered joints, approved gaps, and complete fastening schedule
Ventilation and drainage	Required clearance and drainage maintained beneath the finished platform

E. Preparation — Review and Base Prep

1. Review shed dimensions, use, floor loads, supports, skids, piers, anchors, beams, joists, spans, subfloor, ventilation, drainage, and permits. Confirm the approved plan matches the layout established in Project 03.
2. Confirm the site is graded and drained away from the platform. Do not proceed if standing water, ponding, or reverse slope is present at the footprint.
3. Establish the shed footprint and finished-floor elevation. Cross-check against the protected offsets and reference elevation from Project 03.
4. Prepare and compact the approved gravel pad or support locations. Remove organic material, loose fill, and debris before compacting.

F. Support Installation and Leveling

1. Install skids, piers, footings, or bases at specified spacing. Confirm each support location matches the approved plan before setting.
2. Verify ground-contact treatment and material compatibility. Confirm connectors and fasteners are compatible with the treated lumber before installation.
3. Level supports while preserving site drainage. Recheck each individual support point, not only the corners, using a string line or laser reference across the full footprint.

G. Frame Assembly and Squaring

1. Cut rim and floor-joist members. Confirm each member is cut square and to the length shown in the approved plan.
2. Treat field cuts. Apply the specified preservative to every cut end and drilled hole in treated lumber before assembly.
3. Assemble the floor frame. Build the rim perimeter and install joists at the approved spacing on a level surface where possible.
4. Check dimensions and diagonals. Adjust the frame until both diagonals match within the approved tolerance before securing any permanent connection.
5. Install joists on approved spacing. Maintain consistent spacing and crown orientation across the full frame.
6. Install blocking and connectors. Complete every required blocking and connector location shown in the approved plan.

H. Anchorage, Sheathing, and Inspection

1. Secure the frame to skids or supports. Use the specified connectors and fasteners at every support location.
2. Install uplift or anchorage devices. Complete every anchorage point shown in the approved plan before proceeding to sheathing.
3. Verify frame level, square, bearing, and ventilation. Recheck the full frame against the acceptance standards before any panel is installed.
4. Lay out subfloor sheathing with staggered joints. Confirm panel orientation matches the approved plan.
5. Maintain specified panel gaps. Use the manufacturer-specified spacing tool or gauge at every joint.
6. Apply adhesive only where the floor design requires it. Follow the manufacturer's application instructions where adhesive is specified.
7. Fasten sheathing using the approved schedule. Complete every required fastener location without overdriving or missing framing.
8. Protect panel edges and underside exposure as specified. Apply edge sealant or protection where the approved plan requires it.
9. Check platform plane, square, stiffness, anchorage, drainage, and edge condition. Walk the full platform and confirm no soft spots, movement, or drainage obstruction remain.
10. Complete required floor inspection before wall framing. Record every finding on the shed floor worksheet before Project 15 begins.

I. Recheck and Closeout Procedure

1. Recheck every incomplete or unclear item. Classify each gap as missing documentation, an unconfirmed support elevation, an unresolved connector location, or an unresolved drainage condition before closing it out.
2. Document support and anchor locations. Photograph the finished frame and supports before sheathing conceals them, and file the completed records with the project documentation.