We're looking forward to the American Society of Heating, Refrigerating and Air-Conditioning Engineers' public session on mold to be held during the society's winter meeting in Chicago. The subject of mold may appear relatively straightforward to engineers - it is both preventable and correctable - but the subject holds immeasurable fascination for the public. Listen to home improvement talk shows on the radio and you're sure to hear questions that reveal a high level of anxiety about mold.
Session chair Charles Culp, Ph.D., P.E., of Texas A & M University, says that "sensationalism and bias dominate mold discussion," and that is certainly true. Television news programs are giving mold the "killer bees" treatment: it's coming; you can't stop it; we're doomed.
But those who have experienced a serious mold problem in their homes and local school buildings do not need talking heads to emphasize the dangers. Health effects, property damage, and remediation costs already have convinced the victims that mold is not a phantom menace.
We are especially interested in one presenter's comments during the public ASHRAE session. Joseph Lstiburek, Ph.D., P.Eng., of Building Science Corp., Westford, Mass., has entitled his presentation, "What Happened? Why Mold and Why Now?"
As quoted elsewhere in this issue, Lstiburek says that "mold has been around a long time; what is the big deal now? We've always had roof leaks, plumbing leaks, window leaks, and rain during construction. Buildings don't dry as quickly as they used to. The materials we build out of are much more moisture sensitive. They can't take the moisture 'events' the way the old materials did."
Lstiburek is a forensic engineer who investigates building failures and is internationally recognized as an authority on moisture-related building problems and indoor air quality. He is a member of ASTM and the past chairman of ASTM E241-Increasing the Durability of Building Assemblies from Moisture Induced Damage. He is a voting member of ASHRAE Standard 62 - Ventilation for Acceptable Indoor Air Quality. He is also a voting member of ASHRAE Technical Committee 4.3 Ventilation Requirements and Infiltration and ASHRAE Technical Committee 4.4 Building Materials and Building Envelope Performance.
Despite, or in addition to, these impressive credentials, Lstiburek is also the source of much common sense wisdom on matters such as moisture and mold. Consider, for example, "Joe's Top Ten Rules of Wood Durability," as found on Building Science's Web site, www.buildingscience.com. (It is also telling, and very non-engineering of him, that "Joe" has thirteen items on his top 10 list.) Here are the rules:
1. Buildings should be suited to their environment.
2. The laws of physics must be followed.
3. Three things destroy materials in general and in particular: water, heat and ultraviolet radiation.
4. Of these three, water is the most important by an order of magnitude.
5. Critters love wet materials.
6. No wet materials, no critters.
7. Things get wet let them dry.
8. Things get wet from the inside, the outside, and they start out wet.
9. When the rate of wetting exceeds the rate of drying, accumulation occurs. When the quantity of accumulated moisture exceeds the storage capacity of the material, problems occur.
10. The storage capacity of a material depends on time and temperature.
11. The drying potential of an assembly decreases with the level of insulation and increases with the rate of air flow.
12. As such, energy conservation has the potential to destroy more buildings than architects.
13. Don't let biologists and wood scientists design real buildings.
The ASHRAE public session will be held from 2-5 p.m. Jan. 28 at McCormick Place. Admission is free.
LettersReader says 'living' wage laws don't work
I would like to comment on your editorial entitled, "Living Wage issue raises many difficult questions."
As you may know, the city of Detroit and Ypsilanti Township have passed living wage ordinances in the state of Michigan. The Michigan Legislature has introduced legislation making wages the sole domain of state government.
Several issues are raised with living wage regulations. First, why should a city council decide what is a living wage? A living wage in Grosse Pointe, Mich. (a wealthy Detroit suburb), for example, is significantly different than a living wage in working-class Flint, Mich.
Secondly, the living wage applies to every employee, including skilled craftsmen, secretaries, janitors, valet parking attendants, etc. Shouldn't the market determine the wage for each of these professions, based upon the experience, education, labor supply or shortage?
Thirdly, and probably most importantly, how does a contractor bid work when the base wage varies from one jurisdiction to another? In metro Detroit, for example, there are, I believe, 230 suburbs, each with their own city or village government. It would be virtually impossible for a Detroit-area contractor to keep track of the "living wage" requirements of each jurisdiction.
The State of Michigan and the U.S. government have laws that set a minimum wage. These wages, while far below that which is paid by most contractors, at least is consistent throughout the state. Even McDonalds, today, pays far above the minimum wage just to get employees.
But the wages paid are a function of the available workforce in any given area. East Lansing, Mich. for example, has roughly 50,000 more job-seekers when Michigan State University is in session than during the summer break. The student population forces the wage level down in that community because of the sheer number of potential employees.
"Living" wages just won't work on a city-by-city basis. Contractors deserve to have consistency from jurisdiction to jurisdiction and they must be able to pay people based upon skills, training, and available manpower
Michigan Chapter ACCA