Install Stair Tread, Riser, and Nosing Trim

A. Finished-Project Specification

Quantity: one completed set of riser, tread, and nosing finish trim for the approved stair section, consisting of one riser piece and one tread piece per step, nosing or return trim at every exposed tread edge, a final stair-measurement record, and a completed stair-finish safety inspection.

B. Component Schedule

Component	Quantity	Material	Finished Size	Preparation
Riser trim	1 per riser	Per approved riser detail	Fit to the measured width between skirts or walls at that specific riser	Square-cut ends, dry-fit before fastening
Tread trim	1 per tread	Per approved tread detail	Fit to the measured tread depth and width without reducing required tread depth	Square-cut ends, dry-fit before fastening
Nosing or return trim	1 per exposed tread edge	Per approved nosing detail	Uniform projection matching the structural reference measurement	Profile-matched, coped or mitered return as specified

List every riser, tread, and nosing piece on the stair-trim worksheet by step number. Do not record the flight as a single averaged quantity.

C. Material Takeoff

• Controlling documents: approved tread, riser, nosing, landing, skirt, adhesive, fastener, and finish details for the stair being trimmed.
• Riser, tread, and nosing stock: quantity and stock size per the approved detail, acclimated per the finish specification before cutting.
• Adhesive: type and coverage rate per the manufacturer's instructions for the products specified.
• Fasteners: type, size, and pattern per the approved fastener schedule; do not substitute a fastener not identified in the schedule.
• Barricade materials: signage and physical barrier sufficient to restrict stair use for the duration of the project and the required cure period.

D. Fastener and Hardware Schedule

Use the fastener type, size, spacing, and installation direction stated in the approved stair-finish specification for each of the following joints: riser-to-stringer or riser-to-skirt, tread-to-stringer or tread-to-subtread, and nosing-to-tread. Set every fastener below the walking surface without crushing the profile. Do not use a fastener not identified in the approved schedule.

E. Acceptance Standards

Check	Standard
Rise consistency	Each finished rise matches the structural reference measurement within the tolerance stated in the approved detail or adopted code
Run consistency	Each finished run matches the structural reference measurement within the tolerance stated in the approved detail or adopted code
Tread depth	Each finished tread depth meets or exceeds the structural reference measurement; finish trim does not reduce required tread depth
Nosing projection	Uniform projection at every tread, matching the structural reference measurement within the tolerance stated in the approved detail
Fastener condition	No exposed or proud fastener heads in the walking surface at any tread or nosing
Movement	No tread, riser, or nosing movement, squeak, or deflection under normal walking load after cure
Cure compliance	Stair held out of service for the full manufacturer-specified cure period before final inspection

F. Document Review and Structural Verification

1. Review the approved tread, riser, nosing, landing, skirt, adhesive, fastener, and finish details. Confirm the documents correspond to the stair section being trimmed and record the references on the stair-trim worksheet.
2. Verify the structural stair and geometry have passed inspection. Obtain and record the structural inspection reference before proceeding; do not begin Section G without this confirmation.

G. Pre-Installation Inspection

1. Measure every tread and riser independently. Record rise, run, and tread depth at each step against the structural reference measurement before cutting any finish piece.
2. Inspect for squeaks, movement, damage, protruding fasteners, and moisture. Walk each step under load, check for deflection, and use the moisture meter at any suspect area.
3. Correct structural or fastening defects through the responsible trade before finish installation. Document each defect, refer it to the responsible trade, and reinspect the corrected step before continuing.

H. Barricade and Access Control

1. Barricade the stair and establish safe alternate access. Install physical barriers and signage at both ends of the affected flight, and confirm and communicate the alternate access route before any tread covering is removed.

I. Riser Installation

1. Cut riser trim to fit between skirts or walls. Cut each riser piece to the width measured at that specific riser location, not to an averaged flight dimension.
2. Dry-fit each riser and verify height relationships. Confirm the dry-fit piece preserves the structural reference rise before proceeding to the next riser.
3. Install risers in the approved sequence. Follow the sequence stated in the approved stair-finish specification, coordinating each riser with the skirt board terminations from Project 16.

J. Tread and Nosing Installation

1. Measure and cut tread finish pieces. Cut each tread piece to the depth and width measured at that specific step.
2. Fit tread pieces without reducing required tread depth. Confirm the finished tread depth meets or exceeds the structural reference measurement before fastening.
3. Install nosing or return trim using the specified profile and support. Fit each nosing piece per the approved detail, coping or mitering returns as specified.
4. Maintain uniform nosing projection. Measure the projection at each tread against the structural reference measurement and against the adjacent installed treads.
5. Apply adhesive at the specified coverage. Use the trowel or notched applicator to achieve the coverage rate stated in the manufacturer's instructions.
6. Fasten trim without leaving exposed or proud heads in walking surfaces. Set every fastener below the surface without crushing the profile, using the pattern in the Fastener and Hardware Schedule.
7. Clamp or weight components only as permitted. Use only the clamping or weighting method stated in the manufacturer's instructions for the adhesive and trim product in use.
8. Remove excess adhesive before cure. Clean squeeze-out from the walking surface and joint lines before the adhesive skins over.

K. Verification, Correction, and Cure

1. Verify each completed step for rise, run, tread depth, nosing, level, and movement. Record each measurement against the structural reference on the stair-trim worksheet before moving to the next step.
2. Check transitions at the top landing and bottom floor. Confirm the finished trim integrates cleanly with the landing and floor references without creating a trip edge.
3. Correct loose, proud, slippery, uneven, or trip-producing conditions. Identify the affected step, correct the condition, and reinspect before continuing.
4. Keep the stair out of service through the required cure period. Maintain the barricade and alternate access until the manufacturer-specified cure period has fully elapsed.
5. Document final stair measurements and safety inspection. Record final rise, run, tread depth, and nosing projection for every step, along with the completed safety inspection and the date the stair was returned to service.