Letters

I enjoyed Ted Michelsen's article, "Self-adhering single plies: an emerging technology," October 2007 issue, page 32.

I would like to request clarification of a reference in the article to a study conducted by Carlisle, Pa.-based Carlisle SynTec Inc. regarding the amount of labor required to install 5,000 square feet of Carlisle SynTec's self-adhering membrane (two man-hours with a four-man crew) versus its conventional fully adhered system (12 1/2 man-hours with a five-man crew).

I have asked several roofing contractors about the data in this statement, and there is confusion regarding "total" man-hours for the two systems.

Is it eight total hours for the self-adhering membrane (two hours multiplied by four men) versus 62 1/2 total hours for the conventional system (12 1/2 hours multiplied by five men)?

Or is it simply two total hours versus 12 1/2 total hours?

Thanks for your assistance.

Jack M. Borowski
President
Roofing Products International Inc.
Elkhart, Ind.

Following is Michelsen's response to the letter:

Thank you for your request for clarification. The man-hours are total; the self-adhering membrane takes two man-hours, or a total of 1/2 of an hour with a four-man crew, versus 12 1/2 man-hours, or a total of 2 1/2 hours with a five-man crew, for the conventional fully adhered system.