Newly-built homes throughout Florida are suffering from chronic and systemic humidity and moisture intrusion problems since the 2014 Florida Building Code went into effect.
Code changes are causing air handler units to be installed in mechanical closets with no air conditioning load. There is no load because the walls have been insulated with R-11 insulation and the ceilings are insulated with efficient R-38 insulation rather than R-30 insulation required by previous Codes.
Return air ducts within the mechanical closets are also connected directly to the air handler inlet. The consequence of these design and installation elements is that no warm return air is being circulated over the mechanical closet ceiling surface.
The cold air handler and supply duct absorb heat, keeping the mechanical closet cooler than its surroundings. Supply ducts passing through the ceiling gypsum board make that area colder still.
Additionally, because bathrooms have higher levels of moisture and inherently inadequate moisture removal, the increased supply air caused by the preceding design and construction defects makes bathrooms colder, leading to more mold at bathroom ceilings in a home.
The result is increased mold growth in and near the mechanical closets and bathrooms of a home.
If you or someone you know has noticed mold on bathroom ceilings and on surfaces adjacent to air handler closets, this is likely the cause. Contact Scott N. Gelfand, P.A. for more information.