Standing-Seam Metal Roof Installation SOP
Purpose
Define installation of standing-seam metal roofing - the residential metal roof category most common in 2025. Metal roofs are growing 5-8% per year + premium-priced; quality installation determines 50-year performance.
Scope
Residential standing-seam metal over existing wood deck or open framing. Excludes commercial standing-seam (different gauge + clip systems), exposed-fastener panels (different SOP), + metal tile.
Prerequisites
- Manufacturer's installation manual on-site (legally binding for warranty)
- Permit pulled
- Materials staged: panels, clips, fasteners, trim, sealant
- Crew of 3-5 trained metal installers
- Lift / boom truck for long panels (most metal panels 12-40 ft long)
- Weather window 2-3 dry days, 50-90°F
- Tools: snips, brake, screw gun, seamers, panel cart
Materials
- Metal panels (24-26 gauge typical; 22 gauge premium)
- Clips (concealed-fastener system) - quantity per panel per spec
- Self-drilling screws (#10 typically)
- Closure strips (foam profile matching panel)
- Ridge cap + ridge venting
- Eave + rake trim
- Valley trim (W-valley typical)
- Underlayment: high-temp synthetic (asphalt-modified breaks down under metal heat)
Procedure
Day 1 - Tear-off + dry-in
- Tear off existing roofing to deck
- Inspect deck; replace damaged sheathing
- Install high-temp synthetic underlayment (NOT standard felt - metal heat degrades felt)
- Install ice + water shield in valleys + eaves per code
Day 1-2 - Trim + flashing
- Install eave trim (drip edge specific to metal panel system)
- Install rake trim
- Pre-bend valley metal
- Install valley underlayment + ice + water shield
- Install valley trim
Day 2 - Panel installation
- Square the roof + snap chalk line for first panel
- Install first panel against rake; secure with clip system per spec
- Engage subsequent panels by sliding the seam over the previous panel's lip
- Clip every 12-24 inches along the seam (per spec)
- Continue across roof
- Engage seams completely (often hand-crimped at top)
- Final seam engagement: mechanical seamer crimps to 180° fold (premium)
Day 3 - Penetrations + ridge
- Install pipe penetrations using metal-specific boots (high-temp silicone gasket)
- Cut + form flashings around any roof penetrations
- Install closure strips at ridge + valleys
- Install ridge cap (ventilated if applicable)
- Apply sealant at all overlaps per manufacturer spec
- Inspect every clip + fastener
- Clean all panels with mild detergent + soft cloth
Acceptance criteria
- Panels squared + aligned (within 1/8" over 20 ft)
- All clips installed per spec
- Seam engagement verified (rolled or hand-crimped)
- All penetrations flashed per manufacturer
- Final cleaning: no foot prints, scratches, fingerprints
- Customer signoff
Common pitfalls
- Wrong underlayment: standard felt + metal = warranty void; failure within 5-10 years
- Skipping clip spacing: panels deform in heat (expansion/contraction); seams pull apart
- Mixing metals: aluminum panels + steel screws = galvanic corrosion; match the metal
- No closures: ridge + eave gaps invite wasps, leaves, rodents
- Wrong fastener type: gasketed screws required at penetrations; non-gasketed leaks
- Walking on panels: leaves dents that don't bounce back; only walk in valleys + along ribs
- Not respecting thermal movement: panels expand/contract significantly; clip system allows this; rigid fastening doesn't
Safety notes
- Metal panels are slippery, especially when wet
- Sharp edges everywhere; always wear cut-resistant gloves
- Long panels: 2-3 person carry; use a lift for > 20 ft
- Lightning hazard: stop work in any storm
- Roof edges: harness required > 6 ft
- Heat: metal roof in summer = burn risk; gloves at all times
Metal vs asphalt economics
For customer:
- Asphalt:K typical residential, 20-25 year life
- Metal:K typical residential, 50+ year life
- Cost per year: roughly equal ()
- Insurance: metal earns 10-25% discount in most states
- Resale value: metal adds 1-6% to home value
For installer:
- Asphalt: 8-15% net margin typical
- Metal: 15-25% net margin typical (premium pricing)
- Crew skill: more training, slower learning curve
The single biggest metal-roof callback driver: USING STANDARD ASPHALT FELT UNDERLAYMENT. Metal panel temps reach 150°F+ in summer; standard felt asphalt softens, sticks to underside of panel, degrades. By year 5-8, underlayment fails + leaks appear. High-temp synthetic underlayment is non-negotiable for metal. Spec it; charge for it; install it. The upcharge prevents K+ in liability.
References
- MCA (Metal Construction Association) installation guidelines
- MRA (Metal Roofing Alliance) consumer + contractor resources
- Manufacturer-specific manuals (binding for warranty)
- Manuall internal: Asphalt Shingle Roof Replacement SOP