WeatherStop
Trowel Applied Air & Water Barrier

WeatherStop is a flexible, fibered 100% pure acrylic trowel applied air and water barrier for use with Master Wall Systems.  WeatherStop is available in five-gallon (19L) pails and is mixed 1:1 with Portland cement to a creamy consistency. 

Coverage
160-200 square feet  (14.9-18.6 square meters) - at 1/16" (1.6 mm) thick
Coverages are estimated and vary

Weight:  60lbs (27kg)

Working Time:  1 hour under normal room temerature and humidity.

Drying Time:  12 hours under normal room temperature and humidity.

Application/Storage Temperatures:  40F (5C) to 110F (43C)

Shelf Life:  2 years under normal conditions.

Approved Substrates
Exterior gypsum sheathing (ASTM C79)
Dens Glass Gold®
GlasRoc®
FiberBond®
Durock®
PermaBase®
Concrete
Brick
Masonry
Metal Lath
Others approved in writing

Application Procedure

Job Conditions - Air and substrate temperature for application of  WeatherStop must be 40°F (5°C) or higher and must remain 40°F (5°C) or higher for a minimum of 24 hours.  Providetemporary protection to  protect the wall system from damage until permanent flashings, caps and sealants are installed. Store materials within prescribed temperature limits and out of direct sunlight.  Working and drying times are based upon normal room temperature conditions and will vary with temperature and humidity.

Preparation - The substrate must be approved by Master Wall Inc., clean, dry, structurally sound and free of efflorescence, oil, grease, form release agents and curing compounds or anything that would affect bond.  Painted surfaces are not acceptable and must be removed.

Mixing - Thoroughly stir WeatherStop using a heavy duty 1/2  (12.7 mm) drill at 400 - 500 rpm and a heavy duty mixing paddle.  Pour half of the stirred WeatherStop into a clean plastic pail.  Up to 12 ounces (0.35L) of clean, potable water may be added to adjust workability.  Add Type I or I-II Portland cement to the half pail of  WeatherStop in a ratio of one-to-one by weight and mix to a homogenous consistency.  Let the mixture stand for 3 to 5 minutes and then stir to a creamy consistency.  Do not exceed 24 ounces (0.7L) per pail.  Do not over mix as faster setting or reduced working time can occur.  Do not add accelerators or retarders to the WeatherStop mixture.

Application

For sheathing substratesApply one of the sheathing board joint reinforcing methods noted  below:

Apply 4  (102 mm) Master Wall Self-Adhesive Mesh over the sheathing board joints or embed 4  (102 mm) minimum wide Master Wall Standard or Detail Mesh in WeatherStop.  Cover all joints with an initial coating of WeatherStop and allow to dry to the touch.
Prime joints with Primer 57 and allow to dry to the touch.  Apply 4  (102 mm) WeatherStop Tape on the sheathing board joints.

Water barrier application Apply the WeatherStop mixture over the entire surface of the approved substrate in a thickness of approximately 1/16  (1.6 mm).  Allow to cure completely  before proceeding the Aggre-flex or Aggre-flex Commercial Drainage EIFS or other approved applications.

Clean UpTools and equipment can be cleaned with soapy water while the WeatherStop is still wet.