GAF Roofing Materials & Installation Techniques 2

Question 1

What is the minimum recommended headlap for standard 3-tab asphalt shingles installed on a roof with a 4:12 pitch?

Accepted Answer

2 inches

Answer

A 2-inch headlap is the standard minimum for 3-tab shingles on slopes of 4:12 and above to ensure proper water shedding.

Question 2

Which type of underlayment is best suited for use under metal roofing to prevent galvanic corrosion?

Accepted Answer

Synthetic non-woven underlayment

Answer

Non-woven synthetic underlayments are preferred under metal roofing because they do not retain moisture and lack the acidic compounds found in felt that can accelerate corrosion.

Question 3

When installing GAF Timberline shingles, what is the standard exposure (reveal) for each course?

Accepted Answer

5-5/8 inches

Answer

GAF Timberline architectural shingles have a standard exposure of 5-5/8 inches as specified in the manufacturer's installation instructions.

Question 4

What roofing nail length is typically required when re-roofing over an existing layer of asphalt shingles?

Accepted Answer

1-3/4 inch

Answer

When re-roofing over an existing layer, longer nails (typically 1-3/4 inch) are needed to penetrate through both shingle layers and into the decking.

Question 5

Which flashing material is most compatible with cedar wood shingles to avoid staining?

Accepted Answer

Aluminum

Answer

Aluminum flashing is preferred with cedar shingles because it does not cause the tannin staining that copper produces when rain washes over it onto the wood.

(GAF) GAF Certified Roofing Contractors Practice Test

(GAF) GAF Certified Roofing Contractors Practice Test

GAF Roofing Materials & Installation Techniques 2