Building Research Council 
School of Architecture  University of Illinois at Urbana-Champaign

 

 Moisture Condensation

This circular, Moisture Condensation, describes the causes of excess moisture, how condensation occurs, and methods used to correct moisture problems.

Sample Information

Today, because of insulated building materials that are used for sheathing, walls or ceilings, houses have become more air-tight. If proper ventilation does not occur, excess humidity can built up and produce many problems. Some of these are:
  • Damp spots on walls or ceilings
  • Water, frost or ice on windows
  • Paint blistering or peeling
  • Mildew and mold
  • Deterioration of attic and wall sheathing
One way to rid the house of excess humidity is to install and use exhaust fans in the kitchen and bathroom. However, it is very important that the humid air goes completely outside the house and is not vented directly into the attic. Ideally, the air should be vented directly through an outside wall in the house. If this is not possible, vent the moist air into ductwork in the attic and then vent it out through the soffit.

 
General information about the Building Research Council: brc@uiuc.edu
Publications information at the Building Research Council:  arch-orders@uiuc.edu

Maintained by Webmaster@school.arch.uiuc.edu
 Last updated 2/5/01 sdp

Back to Help For the Homeowner
Go back to the Building Research Council Home Page