Letters

The importance of nail placement

I am writing this letter in response to "A joint effort," March issue, page 24.

I must say, I am disappointed in the statements made in this article. In it, NRCA's Associate Executive Director of Technical Services Mark S. Graham states: "NRCA believes too much emphasis is sometimes placed on manufacturers' exact fastener placement locations."

I would like to know who at NRCA made that statement. It is just wrong. Nail placement is important.

My company is not just a reroofing company; we also perform roof maintenance. We started in maintenance, and workmanship is one of the main causes of roof leaks and failure.

Have you ever seen a roof sliding off? I have. Have you ever seen shingles lying in a yard because the nails had been put in the wrong location? I have. We have pictures and videos on our website talking about this very subject.

Daniel White
Roof Life of Oregon
Tigard, Ore.

Graham responds: I thank White for sharing his comments and opinions.

The document on which my March column was based is Quality Control Guidelines for the Application of Asphalt Shingle Roof Systems. It appears White is basing his comments solely on my column and not the document. The document clearly addresses most of his comments.

Quality Control Guidelines for the Application of Asphalt Shingle Roof Systems is a joint publication of NRCA and the Asphalt Roofing Manufacturers Association (ARMA) and was developed by an NRCA and ARMA joint task force. In addition, NRCA's Technical Operations and Executive committees and ARMA's senior leadership reviewed, provided useful input for and approved the document.

NRCA agrees proper nail placement is an important consideration. This is indicated in the document and in my column in the sentence immediately before the sentence White quotes. However, NRCA also believes too much emphasis sometimes is placed on manufacturers' exact fastener placement tolerances. With some asphalt shingle products, no fastener placement tolerances are provided. In other instances, published tolerances are less than a manufacturer's product manufacturing tolerances. Clearly, this is unreasonable.

Also, research has shown—and a number of asphalt shingle manufacturers agree—once self-sealing asphalt shingles have sealed, fastener placement has little effect on asphalt shingles' wind resistance and overall performance.

Asphalt roof system installation is not an exact science. It is a craft involving skilled professionals who work at elevated heights and in changing weather conditions using a broad range of materials, designs, practices and techniques. The quality of application workmanship is best measured using application criteria and inspection procedures that account not only for roof system perform-ance but also for reasonable variances that are encountered with field application.