Frame a Basic Stair Opening and Landing

A. Finished-Project Specification

Scope: one completed stair-opening layout, floor-opening framing, header installation, and landing frame, built to the dimensions, headers, trimmers, connectors, and landing schedule stated on the approved stair plan, with every open edge guarded and the completed work documented on a signed stair-opening framing record.

B. Required Documentation Schedule

Document	Source	Confirmation Required
Approved stair plan	Design professional / plan set	Current revision on site, including opening size, headroom, and landing size
Header and trimmer schedule	Design professional / plan set	Header size, ply count, bearing, and hanger schedule confirmed
Landing framing detail	Design professional / plan set	Perimeter, supports, posts, beams, joists, and elevation confirmed
Existing floor framing plan	Design professional / Projects 3–4 records	Joist direction, spacing, and bearing at the opening location confirmed
Temporary support plan	Design professional / qualified supervision	Shoring locations, materials, and release conditions confirmed
Permit and inspection requirements	Authority having jurisdiction	Framing and structural inspection scheduled before concealment

C. Layout and Framing Materials

• Trimmer and header stock: species, grade, size, and ply count specified by the approved stair plan; no substitution without a documented revision.
• Hangers and connectors: the exact products specified by the header and trimmer schedule, with listed fasteners only.
• Landing framing materials: perimeter, support, post, beam, and joist stock specified by the landing framing detail.
• Temporary support materials: shoring posts, beams, and cribbing sufficient for the load and duration specified by the temporary support plan.
• Guards and covers: sufficient material to guard every open edge created during this project.
• Documentation: one stair-opening framing record per opening and landing.

D. Acceptance Standards

Check	Standard
Opening width and length	Matches the rough framing limits calculated from the approved finished-opening dimension and finish-material allowance, within the tolerance stated on the approved plan
Opening square	Diagonals of the opening differ by no more than the tolerance stated on the approved plan
Header bearing and connection	Full bearing on each trimmer with the specified hanger, fastener pattern, and seating condition
Trimmer installation	Fully fastened along its full length to the adjacent joist before any supported joist is cut
Landing elevation and support	Matches the plan-specified elevation and bearing, level within the tolerance stated on the plan
Headroom clearance	Meets or exceeds the minimum stated on the approved plan and adopted code, measured from the plan reference point
Edge protection	Every open edge guarded or covered whenever the area is unattended
Documentation completeness	Every required dimension, structural member, connector, and inspection result recorded before the record is signed

E. Layout and Verification (Steps 1–5)

1. Review the approved stair plan, floor-to-floor height, opening size, stair width, headroom, landing size, joist direction, headers, trimmers, posts, and guard requirements. Confirm the plan revision date against the project's document-control log.
2. Confirm that the stair geometry and structural opening have been designed or approved before removing or cutting floor framing. Do not proceed to layout without this confirmation recorded on the stair-opening framing record.
3. Identify the opening location on the subfloor from controlling wall and floor references. Use the reference corners and baseline established in Project 1.
4. Mark the finished opening perimeter, rough framing limits, header locations, and landing position. Calculate rough framing limits from the finished-opening dimension plus the plan-specified finish-material allowance and mark both the finished and rough lines, labeled separately.
5. Verify that the opening does not conflict with beams, bearing walls, utilities, ducts, or other structural components. Cross-check the marked opening against the floor framing plan and any installed utility locations; log and refer any conflict before proceeding.

F. Temporary Support and Controlled Cutting (Steps 6–10)

1. Install temporary support below affected floor members where required by the approved sequence. Position shoring posts and beams per the temporary support plan and verify they are stable before proceeding.
2. Remove only the subfloor area required to expose the affected joists. Cut along the marked rough framing limits using controlled, supported cutting methods.
3. Identify and mark joists to remain, joists to be cut, doubled trimmers, and headers. Mark "cut" and "keep" directly on each joist top before removing any additional material.
4. Install doubled trimmer joists or other side supports before cutting interrupted joists. Fasten each trimmer to its adjacent joist along its full length per the approved schedule before any joist scheduled for removal is cut.
5. Cut joists only at the approved locations using controlled support. Confirm temporary support is carrying the load at each cut location immediately before cutting.

G. Header Installation and Landing Framing (Steps 11–14)

1. Install opening headers with the specified hangers, bearing, or connections. Seat each header fully on its trimmer bearing and install the specified hanger before releasing any temporary support at that location.
2. Connect cut joists to headers using approved hangers and fasteners. Confirm each cut joist end is fully seated in its hanger with the complete specified fastener pattern.
3. Frame the landing perimeter, supports, posts, beams, and joists according to the plan. Follow the landing framing detail for member size, spacing, and connection.
4. Install landing subfloor or temporary decking only after framing inspection permits it. Do not install any walking surface across the landing before Section H's verification is complete.

H. Verification, Guarding, and Documentation (Steps 15–20)

1. Verify opening width, length, square, floor elevation, landing elevation, and clearances. Compare every measurement against the Acceptance Standards table.
2. Check the continuous load path from headers and trimmers to supports below. Confirm each trimmer's bearing point and each header's hanger connection matches the approved schedule with no gaps or missed fasteners.
3. Install temporary guards and covers around all open edges. Guard every edge of the opening and landing before leaving the area unattended.
4. Verify required headroom, approach, landing dimensions, and future finish allowances. Measure headroom from the plan-specified reference point and compare against the plan minimum.
5. Correct authorized framing or alignment deficiencies. Re-verify any corrected dimension, connection, or bearing condition before continuing.
6. Record opening dimensions, structural members, connectors, temporary support, and inspection results. Complete every entry on the stair-opening framing record before signing.