BullsEYE Wall Technology Technical Bulletins

Technical Bulletin #: 1-07 Date: 10/01/2007

SUBJECT: Base Coat Exposure to Moisture Prior to Application of Finish

BULLSEYE Wall Technology (hereinafter referred to as BWT Products) specifications require the following Environmental Conditions for the installation of BWT Exterior Insulation & Finish Systems.

A. The application of wet materials shall not take place during inclement weather unless appropriate protection is provided, protecting the materials from inclement weather until they are dry.
B. At the time of application, air & wall surface temperatures must be a minimum of 40ºF for all BWT Products. The required minimum temperatures must be maintained for a minimum of 24-48 hours or until the products are dry.

These time and temperature requirements are mandatory for all finishes that are applied to a dry basecoat. The basecoat may be exposed to moisture prior to finish application and this moisture may come from various sources, such as rain, dew, frost, snow. Do not allow moisture to get behind the basecoat from improperly flashed parapets.

Allow for the basecoat to dry prior to application of the finish.

This may take several hours of exposure by direct sun to completely dry the surface area. Shaded areas with only partial sun may require additional drying times to avoid wash-offs and other surface problems. Total sun will increase the surface temperature of the basecoat. If the basecoat is saturated from rain and other moisture sources and has not been allowed to dry out it is highly likely that the basecoat is too wet for finish application.

Please evaluate any and all surfaces prior to application of finish by doing the following: compare the exterior wall area to a dry sample that has not been exposed to moisture. Dark or blotchy areas shall be suspect that the wall is too wet for the application of finish coat.

Recognition of saturated and damp base coat conditions prior to the application of finish can avoid most problems that are incorrectly attributed to problems with a finish. The overnight dry time period for drying of finishes is greatly extended when the application is done over a damp base coat, during low temperatures and during times of high humidity. Finish may appear dry, but adhesion can be very weak since the finish was never able to create the required suction to the base coat. Damp base coat inhibits suction thus preventing the finish from developing adhesion to the basecoat.

Use of a moisture meter will help in determining whether a basecoat is dry enough for finish to be applied.

Technical Bulletin #: 1-07 Date: 10/01/2007

SUBJECT: Drying Conditions for BWT Finishes – Climatic Drying Conditions

A. The application of wet materials shall not take place during inclement weather unless appropriate protection is provided, protecting the materials from inclement weather until they are dry.

B. At the time of application, air & wall surface temperatures must be a minimum of 40ºF for all BWT Products. The required minimum temperatures must be maintained for a minimum of 24-48 hours or until the products are dry.

These minimum requirements are to assure resistance to wash-off from direct rainfall exposure and will safeguard long-term performance. All BWT Finishes are water-based which require the evaporation of water for drying to proceed. Low temperatures & high relative humidity retard the evaporation of water and prolong the required time for drying of the finishes.

High relative humidity requires additional time for drying, no matter what the temperatures are. As temperatures fall in the late afternoon or evening, dew can form on wall surfaces with moderate to high relative humidity conditions. Light deposits of dew completely inhibit the drying of BWT Finishes until it evaporates and may also affect color. Dew will completely saturate base coat on shaded elevations and will remain saturated until it is exposed to bright direct sunlight for more than 2 hours.

The protection of materials includes EPS board. The EPS board, if wet, must be allowed to dry out prior to application of the basecoat. Wash-offs and blister problems involve application of the finish over a base coat that is only partially dry. Wash-off or blisters will occur to areas where the basecoat is saturated or damp and a finish is applied over those areas. It is extremely important that finish is only applied over a dry base coat when climatic conditions are marginal. See Technical Bulletin #1-08 for more information on damp base coat.

Whenever possible, you should store finishes at 70ºF or above prior to application when the outdoor temperature is 50ºF or below. Drying will be increased significantly thus reducing the potential for wash-off.

Sincerely,

BULLSEYE Wall Technology