NC Roofing Contractor cheat sheet

Asphalt shingles are graded by ASTM D3462 (mineral-surfaced) and D7158 (wind resistance classes A–D); class ratings assume correct nailing, underlayment, and edge metal.

Steep-slope systems are defined as slopes ≥ 2:12 (some codes use ≥ 3:12 for shingles); slopes below 4:12 require double underlayment for asphalt shingles per IRC R905.2.

Low-slope membranes include EPDM (thermoset, heat-weldable seams), TPO and PVC (thermoplastic, hot-air welded), and modified bitumen (SBS styrene-butadiene-styrene for cold flexibility, APP atactic polypropylene for heat-welded application).

Built-up roofing (BUR) is specified by ply count (e.g., 4-ply) with a surfacing; coal-tar pitch and asphalt are not interchangeable and must not be mixed in the same membrane.

Metal roofing panels are classified as structural (exposed fastener) or architectural (standing seam, concealed clip); thermal movement requires clip and fastener detailing, not rigid pinning.

Underlayment choices: No. 15 felt (ASTM D226 Type I), No. 30 felt (Type II), and synthetic polymer sheets; ice-dam protection membrane is required at eaves in areas with a history of ice damming.

Roof deck types: wood structural panels (OSB/plywood), steel deck, structural concrete, and gypsum; each has distinct fastener type, pull-out capacity, and membrane attachment rules.

Vapor retarders belong on the warm side of the insulation; in vented attics, ceiling-level retarders are used, while unvented assemblies rely on airtight rigid insulation above the deck.

Asphalt shingle nailing: 4 nails per shingle for slopes < 20:12, 6 nails for slopes ≥ 20:12 or when required by the manufacturer or high-wind rating; nails must be placed in the nail line, not above or below.

Fastener penetration into wood decking must be at least 3/4 inch; over-driven or angled fasteners are defects that reduce wind uplift capacity.

Shingle exposure is set by the manufacturer's headlap; standard 3-tab shingles use 5-inch exposure, while architectural shingles use their specified exposure and stagger pattern.

Metal panel installation requires a minimum slope (often 3:12 for standing seam) and correct clip spacing; fastener gaskets must be compressed, not crushed, to seal.

Single-ply membrane seams must be tested (probe, air lance, or vacuum) after welding; seam strength is verified against the manufacturer's minimum peel and shear values.

Flashing details: step flashing at sidewalls interleaved with shingle courses, counterflashing at masonry, and cricket installation at chimneys wider than 30 inches.

Ventilation: net free vent area (NFVA) should provide 1:150 of attic floor area, or 1:300 with balanced intake/exhaust and a vapor retarder; intake and exhaust must be balanced.

Roof slope conversion: slope in inches per foot × 1.0 gives rise; pitch angle = arctan(rise/12). A 6:12 slope equals 26.57 degrees.

Leak diagnosis starts at the point of water entry, not the stain; water can travel along the deck, so trace uphill and along flashing terminations.

Repair scope decision rule: localized damage within one shingle course is a repair; widespread granule loss, multiple leaks, or deck deterioration indicates replacement.

Ponding water is defined as water remaining on a low-slope roof 48 hours after rain; causes include inadequate slope, clogged drains, and deflection.

Maintenance schedule: inspect roofs at least twice yearly (spring and fall) and after major storms; clear drains, scuppers, and gutters of debris.

Shingle replacement requires matching the existing exposure and color lot; mismatched lots are a common source of owner complaints, so document existing materials.

Roof tear-off and replacement may trigger code upgrades: ice barrier, drip edge, and ventilation requirements apply to the new roof assembly, not necessarily the old one.

Blister and ridging repairs on low-slope membranes require cutting, drying, and patching rather than surface coating, which traps moisture.

Record-keeping: photograph pre-existing conditions, retain material receipts, and document warranty terms; manufacturer warranties often require registration within a set period.

North Carolina adopts the International Residential Code (IRC) and International Building Code (IBC) with state amendments; roofing chapters are IRC Chapter 9 and IBC Chapter 15.

IRC R905 governs steep-slope roof coverings; IBC Chapter 15 governs roof assemblies and rooftop structures for commercial buildings.

Ice barrier requirement: IRC R905.1.2 requires an ice-dam protection membrane at eaves where the average January temperature is 25°F or below, or where ice damming has occurred.

Drip edge is required at eaves and gables per IRC R905.2.8.1 and must be installed under the underlayment at eaves and over it at rake edges.

Fire classification: roof coverings are rated Class A, B, or C per ASTM E108; most jurisdictions require Class A or B for new construction.

Wind resistance: shingles must be tested per ASTM D7158 or D3161; the required class depends on the design wind speed from ASCE 7.

Attic ventilation: IRC R806 requires 1:150 NFVA unless balanced ventilation and a vapor retarder allow 1:300.

Permits: roofing permits are required for new construction and most replacements; repairs may be exempt depending on local jurisdiction and scope.

OSHA fall protection: 29 CFR 1926.501 requires fall protection at 6 feet or more above a lower level for construction; roofing work on low-slope roofs within 6 feet of the edge requires guardrails, safety nets, or PFAS.

Fall protection systems: personal fall arrest (harness, lanyard, anchor) requires anchorage rated at 5,000 lb per worker or engineered equivalent, and prompt rescue.

Ladder safety: 4:1 slope rule for extension ladders, 3 feet of extension above the landing, and secure tie-off at the top.

Roof edge warning lines are set back at least 15 feet from the edge on low-slope roofs; warning lines alone are not fall protection unless combined with a safety monitoring system.

Ladder and roof access: portable ladders must be inspected before use; damaged ladders are removed from service, not repaired with makeshift parts.

Heat illness prevention: water, rest, shade; acclimatize new workers, and know the signs of heat exhaustion versus heat stroke (altered mental status = emergency).

Hazard communication: Safety Data Sheets (SDS) must be available for roofing adhesives, sealants, and solvents; use respiratory protection per label.

Electrical and tool safety: ground-fault protection on temporary power, lockout/tagout for equipment, and eye protection when cutting shingles or metal.

Estimating: square = 100 square feet of roof area; order 10–15% waste for shingles, more for complex hips/valleys, and compute pitch multiplier for slope.

Pitch multiplier = sqrt(1 + (rise/12)^2); a 6:12 slope has a multiplier of about 1.118, applied to plan area to get actual roof area.

Labor productivity benchmarks vary by system; track crew-days per square to build reliable estimates rather than using generic rates.

Change orders must be written, signed, and priced before work proceeds; verbal changes are the leading cause of payment disputes.

Cash flow: retainage (often 5–10%) is withheld until substantial completion; bill progress payments and track lien rights deadlines.

Schedule management: sequence tear-off, deck repair, underlayment, and finish; weather delays should be documented with daily logs.

Subcontractor management: verify licenses, insurance certificates, and written scopes; back-charges require notice and documentation.

Key performance metrics: gross margin per job, call-back rate, and days from contract to completion; review these monthly.

North Carolina requires a written contract for residential roofing above a threshold amount; the contract must include the contractor's license number, scope, price, and payment terms.

North Carolina's three-day right to cancel applies to certain home solicitation sales; the notice must be provided in writing at the time of contract.

Lien rights: a contractor must provide a Notice to Lien Agent and file a claim of lien within 120 days after last furnishing labor or materials on the project.

Mechanics' lien deadlines: a claim of lien must be filed within 120 days of last furnishing; a lien enforcement action must be filed within 180 days of filing the lien.

Warranty terms: distinguish manufacturer material warranty from contractor workmanship warranty; workmanship periods typically run 1–5 years and must be stated in writing.

Insurance: general liability and workers' compensation are required; certificates of insurance should name the owner as additional insured where required.

Dispute resolution: contracts should specify mediation/arbitration and governing law; North Carolina courts apply the state's construction defect statute of repose (6 years for improvements to real property).

Consumer protection: unfair or deceptive trade practices (UDTP) claims under N.C.G.S. 75-1.1 can expose contractors to treble damages and attorney fees.

North Carolina roofing contractors are licensed by the North Carolina Licensing Board for General Contractors (NCLBGC); roofing is a specialty classification under the general contractor licensing framework.

License required: a contractor must be licensed before bidding or contracting for roofing work; the license is held by the qualifying individual and the business entity.

Qualifying exam: applicants must pass the roofing specialty exam and meet experience requirements; the license is issued to the business, with a designated qualifier.

Continuing education: North Carolina requires 8 hours of continuing education annually for license renewal, including mandatory hours on licensing laws and safety.

License display: the license number must appear on contracts, bids, and advertising; failure to display is a board rule violation.

Unlicensed contracting is a misdemeanor and can result in civil penalties; contracts entered into by unlicensed contractors may be unenforceable.

Board discipline: the NCLBGC can suspend, revoke, or restrict licenses for incompetence, misconduct, or code violations; complaints are filed with the Board.

License renewal: licenses renew annually; late renewal may require reinstatement fees and continuing education completion.