Eliminate Moisture Source to Eliminate Mold Growth

[Editor’s Note: This letter is in response to the letter “Structure Cooking to Rid It of Mold?” Oct. 8.]

Bill Johnson wrote an interesting letter regarding the concept of “cooking” a building to prevent future mold growth after a major water problem. There is a nice reference book on mold growth in buildings published by ASHRAE, Humidity Control Design Guide for Commercial and Institutional Buildings, which can be applied to many residential problems as well.

Mold needs four things to grow: spores to get it started, a temperature that is suitable for its growth, a food source, and a moisture source. Mold spores are virtually everywhere, as it is nearly impossible to completely eliminate them. Different types of molds grow in a variety of temperature conditions, as we find by molds that grow on food in our refrigerators as well as in warm environments. Almost anything can support mold in terms of food supply, from wood or paper products to even just a dust layer on a metallic or plastic surface.

The only one of the four necessities that we can control is the moisture source. Mold grows in houses when there is a major moisture intrusion, providing this necessary water supply to the existing spores. Once mold reaches a certain stage, it can sustain its own moisture needs. That is when it must be killed and removed and the moisture supply eliminated.

What Mr. Johnson is proposing would be a way to dry out the structure to eliminate the moisture, but I don’t think it could ever kill all the mold spores, and certainly would not prevent new spores from coming in with outside air. If there is an adequate supply of moisture, even from just high humidity conditions, the mold spores and food supply are still there and can start new mold growth all over again. In humid climates, the use of air conditioning is just as important for the humidity control it provides as it is for the temperature regulation.

William E. Murphy, Ph.D., P.E., Director
Engineering Extended Campus Programs – Paducah
Professor of Mechanical Engineering
University of Kentucky
Paducah, Ky.


What's Behind Global Warming?

[Editor’s Note: This letter is in response to Joanna Turpin’s column “Is Carbon Really the Culprit?” Oct. 29.]

Joanna Turpin wrote a very well thought-out column. Now watch out for the global warming cult to start attacking her. I hope they don’t.

A number of years ago I met Carl Sagan here in Sturgis. He told us we were killing our grandchildren with Freon. I have 13 of them.

When I asked him how the Freon got 25 miles high, he changed the subject.

Lawrence A. Franks
Director-Secretary/Treasurer
Burr Oak Tool Inc.
Sturgis, Mich.


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Publication date:11/12/2007