Install Horizontal Lap Siding

A. Finished-Project Specification

Scope: one completed horizontal lap-siding installation covering one prepared wall elevation, from the first course engaged with the starter strip to the approved top termination, including all field-cut boards, staggered joints, and fitted openings on that elevation.

B. Required Documentation Schedule

Document	Source	Confirmation Required
Siding product instructions	Manufacturer	Exposure, overlap, fastening method, and joint treatment confirmed for the selected product
Siding layout references	Project 11 record	Starter, corner, and control-line locations confirmed current and undamaged
Rainscreen and WRB inspection records	Projects 2–3 and 10 records	Confirmed passed before siding begins
Window and door flashing records	Projects 4–9 records	Confirmed passed and undamaged before siding fits around openings
Fastening schedule	Design professional / manufacturer	Fastener type, location, spacing, and seating condition confirmed
Change documentation	Design professional / general contractor	All approved field changes incorporated

C. Installation Materials and Consumables

• Siding stock: the approved horizontal lap siding product and profile, staged and conditioned per the manufacturer's storage requirements.
• Fastener stock: corrosion-resistant siding fasteners matching the approved fastening schedule for the backing and siding thickness at this elevation.
• Joint accessories: approved joint flashing, splines, or proprietary joiners specified by the siding system, for use only where the system requires them.
• Edge treatment: the approved sealer, primer, or coating for field-cut siding edges, applied per the manufacturer's instructions.
• Documentation: one siding installation record per elevation as required by the project specification.

D. Acceptance Standards

Check	Standard
Exposure	Matches the approved specification at every course across the elevation, checked against the transferred control lines
Alignment	Every course level and aligned to the control lines within the approved tolerance at the specified check interval
Fastening	Fasteners seated at the approved location, spacing, and depth, into approved backing, without overdriving or restricting movement
Joint distribution	Butt joints staggered per the approved pattern and located over approved support
Clearances and expansion gaps	Required clearances at roofs, decks, grade, paving, flashing, trim, openings, and corners maintained per the approved specification
Drainage	Rainscreen drainage and ventilation openings remain unobstructed by siding, fasteners, or joint accessories
Documentation completeness	Layout references, corrections, photographs, and the completed elevation record are recorded on the siding installation record

E. Document Review and Material Preparation (Steps 1–5)

1. Review the siding product instructions, exposure, overlap, blind- or face-fastening method, joint treatment, end gaps, paint or sealing requirements, and storage limits. Confirm the current manufacturer instructions match the product staged for this elevation.
2. Confirm the starter, corners, opening trim, flashing, and rainscreen have passed inspection. Verify each prior inspection record shows the required approval before uncovering or disturbing any of those components.
3. Inspect siding for damage, moisture condition, coating defects, straightness, and product identification. Set aside any board that fails inspection rather than installing it and marking it for later replacement.
4. Store and stage siding flat, dry, supported, and protected from soil and weather. Confirm staging keeps the material within the manufacturer's exposure limits before installation.
5. Select boards or courses to distribute color, texture, and joints according to the approved appearance plan. Lay out an entire course, or several courses, before fastening any board to confirm the distribution across the full elevation.

F. First Course and Cutting (Steps 6–9)

1. Measure the first course from controlled corner and trim references. Use the corner projection and control line established in Project 11, not a field estimate.
2. Mark cuts using the designated reference face and end. Follow the siding manufacturer's specified reference face and end for every marked cut.
3. Support the material and cut it using the specified blade, tool, dust control, and edge-treatment method. Support both sides of the cut to prevent binding or splintering.
4. Seal, prime, or coat field-cut edges where required. Apply the approved edge treatment before the board is installed, not after.

G. Course Installation and Fastening (Steps 10–13)

1. Install the first course fully engaged with the starter and aligned to the level control line. Confirm full engagement along the entire course length before fastening.
2. Maintain required clearances at roofs, decks, grade, paving, flashing, and trim. Verify each clearance against the approved specification before proceeding to the next course.
3. Fasten into the approved backing with the specified corrosion-resistant fasteners, location, spacing, and seating condition. Confirm each fastener penetrates the specified backing, not only the siding and furring.
4. Do not overdrive fasteners, restrict required movement, or nail through prohibited areas. Adjust tool pressure or depth setting and correct any overdriven fastener immediately.

H. Successive Courses and Joint Management (Steps 14–19)

1. Install successive courses with the required exposure and overlap. Measure exposure from the control line, not from the course immediately below.
2. Check alignment against control lines at the specified interval. Correct drift at the course where it is found before continuing upward.
3. Stagger butt joints and locate them over approved support. Confirm no two adjacent courses share a joint location within the approved minimum offset.
4. Install joint flashing, splines, sealant, or proprietary joiners only where the siding system requires them. Do not add sealant at a joint the approved system leaves open.
5. Maintain expansion gaps at trim, openings, corners, and transitions. Verify each gap against the approved specification before fastening the adjacent board.
6. Fit courses around penetrations and mounting blocks without blocking drainage. Confirm the rainscreen drainage path remains open at every penetration the course passes.

I. Termination, Inspection, and Documentation (Steps 20–23)

1. Install the top termination using the approved flashing, trim, or concealed fastening method. Confirm the termination detail matches the approved specification for this elevation.
2. Inspect exposure, level, joint distribution, fastening, edge treatment, clearances, drainage, and surface damage. Complete this inspection across the full elevation before considering it finished.
3. Correct drift, cracked boards, overdriven fasteners, tight joints, reverse laps, and unsupported ends. Reinspect each corrected location against the Acceptance Standards table.
4. Clean the elevation and document the completed installation. Photograph the full elevation and label each photograph with its location before closing out this project.