but it is not waterproof. Neither is it, as thought by 
many, porous. In fact, when liquid water penetrates 
stucco cladding on a building, it almost always does so 
not through the field of the stucco but through breaches 
at cracks, control joints, perimeters of openings such as
doors and windows and joints with abutting materials. 
In a properly designed stucco clad wall, water from these
breaches is expected to penetrate no further than the 
Window Fitters Guide to Window Installation
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Coastal 
CMU Installation 
with Installed Buck
Coastal Installation
Stucco finished homes are prevalent in coastal areas of the
US and with the advent of Hurricane Code Standards in
Florida and elsewhere, installation of products for these
areas require different details, techniques and procedures.
Stucco Finish
A building system utilizing stucco as a wall cladding is
generically known as a drainage wall, a wall system in
which the outermost material provides a substantial 
barrier to water and a secondary material, typically a
weather resistive barrier (WRB), provides a backup barrier
to water that may penetrate the cladding. Penetrating 
water is intended to flow by gravity to the exterior 
outside of the WRB and is prevented from reaching 
water-sensitive materials. 
There are two types of drainage walls: membrane 
drainage walls and cavity drainage walls. A system 
utilizing stucco is an example of a membrane drainage
wall, whereas a system using masonry veneer is usually
designed as a cavity drainage wall. In drainage walls, 
evaporation may also play a role in moisture dissipation,
but is a comparatively slower process subject to weather
conditions. 
As a material, stucco can provide a high resistance to 
passage of liquid water if properly formulated and cured,
Typical Flanged Window in 
Stucco Veneered Block or Frame Wall
SAMPLE MANUAL

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