Snap-loc 24, Design / installation considerations – Metal Sales Snap-Loc 24 Installation User Manual

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SNAP-LOC 24

DESIGN / INSTALLATION CONSIDERATIONS

(CONT.)

VENTILATION

VENT AT EAVE

BUILDING WITH ATTIC OR RETROFITTED

TYPICAL METAL BUILDING (NO ATTIC)

Proper design and installation of vapor barriers and ventilation systems are important to prevent
condensation and the resulting problems of moisture damage and loss of insulation efficiency.

Condensation occurs when moisture laden air comes in contact with a surface temperature equal to or
below the dew point of the air. This phenomenon creates problems that are not unique with metal
buildings; these problems are common to all types of construction.

The underside of the metal roof on a typical metal building (no attic) should be protected from con-
densation by insulating with a faced insulation. This should reduce the potential of condensation
forming on the underside of the panels.

On buildings that have an attic space or are being retrofitted with a metal roofing system, vents should
be placed at both the eave and peak of the roof in order to prevent a buildup of moisture (humidity) in
the attic space.

VENT

ATTIC INSULATION

VENT

WALL VENTS OR
OPENINGS

INSULATION