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Barrier Systems (continued)
The barriers are as much systems as they are
materials. The function of the barriers is to
prevent any water penetration into the substrates.
They include metal, glass, and composite
materials such as sheet and liquid membranes for
vertical and horizontal applications.
The most popular system today is the
elastomeric, which is a waterproofing material
with the ability to return to its original shape and
size after substrate movement during expansion
or contraction.
Elastomeric is used mainly as a remedial system,
because the original barrier, such as the building
paper, is no longer performing, or the original
design or application was not adequate.
Elastomeric works the same way as your skin; it
allows the flesh (substrate) to breathe, but does
not allow the water to penetrate.
In most cases, the original barrier is abandoned
when the elastomeric coating is applied. It is an
economically attractive option compared with
the cost of removing the sacrificial materials and
the building paper then reinstalling the barrier.
Elastomeric materials should not be considered
as a technological breakthrough, but as an
economical way to provide an alternate barrier.
As the original barrier and diversion system are
abandoned, the barrier is moved to the surface of
the wall where transition joints are critical.