Mold Control Information Series – Article #2

If you need mold control assistance discussed in this article call us at 1-800-344-4414 or email us at info@atlenv.com for details and a free estimate.

Written by Robert E. Sheriff, MS, CIH, CSP, President

November 21, 2018

Controlling Condensation – Controlling Mold

You know those water stains on the ceiling tiles in your office that you are certain are caused by a leaky roof? Of course, the maintenance man thinks you’re crazy, since your office is not on the top floor. He dutifully changes the ceiling tile and a month later the water stain is back, but this time it has those little black circles that look like mold colonies.

Sound familiar?

There seems to be as many problems with condensation from piping, ductwork, windows, skylights, and even walls, as there are with leaky roofs.  Maybe now especially in a multi-story building!  What’s worse is that a leaking roof usually can be located and repaired. Condensation points tend to be overlooked, ignored or unresolved. Piping is the most common source of condensation. These cold water, chilled water, or refrigerated lines may be un-insulated or only partially insulated. They should be completely insulated, at elbows, valves, and connection points to stop them from dripping onto the ceiling. Lurking especially behind walls, condensate collects on floors and soaking wallboard until mold becomes visible.  A persistant problem is that the insulation only has a limited life.  Depending on the type and quality of the material it may last 2 to 3 years or up to 10 or 20 years.  Sadly, you get what you pay for!

Air conditioning ductwork can also be a problem. It is not unusual to have fiberglass lined ducts with an aluminum foil covering. If the foil covering is broken or deteriorates due to age, dirt and moisture gets into the fiberglass and soon the duct turns into a mold incubator. These are often culprits when the office smells moldy or people get sinus troubles and there is no visible evidence of mold growth.  Some older ductwork has a tar paper lining- old and probably deteriorating by now since it hasn’t been used for the last 15-20 years.

Condensate on the interior of windows can also result in mold growth. Water drips to the floor, window ledges, or knee walls, and creates a growth environment. Well-constructed buildings often contain “weep holes” or “weeps” to drain interior water to the outside. These can get plugged during construction or renovation or just get plugged over the years with dust and dirt. They are not easy to open because they are often embedded in the skin of the building. The same situation often happens with skylights.  The result – mold growth.

Interior walls by themselves may even be sources of condensation. When the space of one side of a wall is warm and the opposite side much cooler, moisture can form on the wall. This is more common in commercial buildings that use metal studs or in residential basements where metal studs are set against damp walls. The metal conveys the cooler temperature better than wood. Insulation seems to be effective in these situations.  This certainly is the case where an outside wall is below ground level.  Condensation is a constant problem there.

Recognizing that condensate may be the problem and not a leaky roof or pipe can be the greater part of the solution. Dealing with condensation through proper and complete insulation and drainage is the final piece of the puzzle to a mold-free building environment.

Written by Robert E. Sheriff, MS, CIH, CSP, President

Our primary service areas for Mold Control Services  are: NJ, NY, NYC, PA, CT, DE, (Boston) MA, RI, Wash DC, WI, MD, MI, (Chicago) IL, VA, IN, (Atlanta) GA, AL, NC, SC, TN, (Dallas, Ft Worth) TX, OK, DC, AR, we can service most other areas of the U.S. but with some added travel charges.