Condensation on Metal Roofs To the Editor: The article "Installing Metal Panel Roofs" by Chad Taylor (5/00) was informative and interesting. In many years of building additions and remodeling in the Northeast, I have been interested in problems related to moisture entrapment and inadequate ventilation. The company featured in the article, with nearly 40 years' experience, has obviously been doing its work satisfactorily. However, while their practice of installing roof panels directly over asphalt felt may be appropriate in Florida, it may not be applicable to northern climates. Condensation on the underside of roof panels from moisture entrapment and wide daily and seasonal temperature variations may result in corrosion and eventual perforation from underneath. Recommendations I have encountered call for the installation of
