9 / 150
-
3-
2. Surface tension.
Water adheres
to the surface of an opening and
travels inward along it.
3. Capillary action.
Water travels
inward because its adhesion to the
walls of an opening is stronger than
the cohesive forces between the
liquid molecules. This occurs in
very porous substrates.
4. Wind / air currents.
The wind
currents can create sufficient air
pressure to force the water upward
and over the components.
5. Hydrostatic pressure.
Pressure
applied to the building envelope
materials by various heights of
water at rest.