Apartment and Condominium buildings in Chicago and suburbs built before 2000 were built under outdated building codes. These codes did not take attic ventilation into account. Consequently, many older apartment and condominium complexes are encountering attic mold issues.
As building sciences evolve, much has been learned about attic moisture and mold related issues, over the past few decades. Accordingly, new building codes have been put into place to circumvent such problems.
Moisture vapors from cooking, bathing, and other activities can rise up into the attic, particularly in winter when windows and doors are kept closed. Without proper attic ventilation, the moisture vapors can collect in the attic, on the underside of the roof deck and other attic surfaces. Over time, this moisture buildup can lead to mold and/or structural wood rot. (Click here to learn more about mold)
BATHROOM EXHAUST FANS
Attic exhaust fans are designed to remove odor and moisture from the bathroom. Prior to new building codes, bathroom exhaust fans were frequently exhausted into the attic, for both single family and multi-family dwellings. Many mold problems can be traced back to this practice.
When a bathroom fan is exhausted into the attic, the moisture in the air will condense on the underside of the roof sheathing and other surfaces, including insulation. Moist or wet insulation can dramatically reduce the thermal resistance of insulation. This often means homeowners will run their heating system longer and more frequently to maintain ideal room temperatures and will lead to higher heating costs.
THE PROBLEM WITH HUMIDIFIERS
The popularity of humidifiers, over the past 30 or 40 years, have also added to the problem. Humidifiers are used to add moisture to the air to prevent dryness that can cause irritation in many parts of the body. Too often, these devices are set too high and the excess moisture also escapes to the attic adding additional moisture.
ILLINOIS BUILDING CODE FOR ATTIC VENTILATION
2015 attic ventilation building code requires 144 cubic inches of net free air space for every 150 square feet of attic space divided by 2, roof vents – 50% at peak and 50% at the soffit. Many older complexes don’t come close to these specifications.
ILLINOIS BUILDING CODE FOR BATHROOM FAN EXHAUST
New codes call for bathroom exhaust fans to be exhausted through the roof to a dampered roof cap via R’8 insulated duct. This method exhausts the moist bathroom air outside, rather than into the attic.
SIGNS YOU MAY HAVE A PROBLEM
Attic moisture and mold problems can go undetected. There are very few telltale signs. And when signs do appear, the problems is often in an advanced state. Here are the few indicators of trouble:
- If you have stains where the ceiling meets an exterior wall of your unit (inside), you should have your attic inspected.
- If you notice moisture dripping out of your bathroom exhaust fan, your bathroom exhaust may be exhausting into your attic.
- If you notice condensation around canned lighting, smoke detectors, or light fixtures, you may have attic moisture problems.
- Unexplained allergy related symptoms
SUSPECT A PROBLEM?
Not sure what to look for? Call The Attic Experts for a FREE attic inspection today at 630.941.3800.