GAF Case Analysis & Practical Application 3

Question 1

A customer wants to re-roof over an existing layer of 3-tab shingles. The deck shows no rot, but the existing shingles have cupping. What is the correct approach per best practices?

Accepted Answer

Tear off the existing layer before installing new shingles

Answer

Install new shingles directly over the cupped layer

Answer

Nail down the cupped shingles flat before overlaying

Answer

Apply roofing cement to the cupped areas and proceed with overlay

Question 2

A GAF Certified contractor inspects a 3-year-old roof with shingle blow-offs. The installation records show 4-nail patterns were used in a high-wind zone rated for 6 nails. What warranty consequence applies?

Accepted Answer

The warranty is voided because the installation did not follow GAF's high-wind nailing requirements

Answer

The manufacturer covers the blow-offs under the standard limited warranty

Answer

Only a prorated partial warranty applies based on years in service

Answer

The contractor's general liability policy covers it without warranty impact

Question 3

During reroofing, a contractor discovers the roof decking has a 1/2-inch gap between OSB panels throughout. What action should be taken before laying underlayment?

Accepted Answer

Install H-clips and ensure panels have proper 1/8-inch spacing, replacing panels if over-spaced

Answer

Proceed since small gaps are within tolerance

Answer

Fill gaps with roofing cement and continue installation

Answer

Overlay with 1/4-inch plywood before installing underlayment

Question 4

A homeowner calls 6 months after installation complaining of interior ceiling stains below a skylight. The contractor installed new flashing per the skylight manufacturer, but not per GAF's flashing guidelines. Who bears responsibility?

Accepted Answer

The roofing contractor, for not following GAF's required flashing methods

Answer

The skylight manufacturer, since their flashing was installed

Answer

The homeowner, for choosing a non-compatible skylight

Answer

Shared equally between GAF and the skylight manufacturer

Question 5

A steep-slope roof (10:12 pitch) requires workers to use fall protection. A subcontractor wants to use only toe boards. What is the OSHA-compliant and best-practice approach?

Accepted Answer

Personal fall arrest systems or a safety net system are required on roofs above 6:12

Answer

Toe boards alone are sufficient on slopes above 8:12

Answer

Toe boards plus warning lines are acceptable above 8:12

Answer

No fall protection is required since workers are experienced

Question 6

A flat roof section over a garage has been leaking at the parapet wall. The previous contractor used standard steep-slope shingles up the parapet. What is the correct repair?

Accepted Answer

Remove the shingles, install base flashing and cap flashing at the parapet per low-slope specs

Answer

Extend the shingles higher up the parapet and add more roofing cement

Answer

Caulk all visible gaps around the shingles at the parapet

Answer

Add a metal cap to the parapet top only

Question 7

A contractor is asked to install a new GAF roof on a home where the attic has open soffits but no ridge vent. The homeowner declines to add a ridge vent. What is the best course of action?

Accepted Answer

Document the homeowner's refusal in writing and note potential warranty limitations before proceeding

Answer

Proceed and install shingles; ventilation is the homeowner's responsibility

Answer

Refuse the job entirely since ventilation cannot be waived

Answer

Install power ventilators on the roof without the homeowner's approval