Questions and Answers for Westpac Materials 18 lb. Fast Set 20 Lite Setting-Type Powder Joint Compound

A:  You should wait a minimum or 24 hours. Even know its set up it still needs to be completely dry.

A:  The purpose of setting type compound is so that multiple coats of mud can be applied in rapid succession. Thus, it is not necessary to wait for it to dry before applying the next coat of mud. HOWEVER for sanding and painting, one must still wait for it to be completely dry. The duration of which is wildly variable. 20 minutes is the setting time for this joint compound. That means it will become hard only, but not dry necessarily. This duration is UNRELATED to the drying time. Drying time is similar to any other joint compound, both setting type and premixed varieties, and it is dependent on the application thickness, the temperature and the humidity in the room applied. Very thin layers could be completely dry in under 45 minutes, thick applications (first coats usually) in unheated rooms can take days to dry out.

A:  After the set time you wait 60 minutes before painting.

A:  Like stated elsewhere dry times will vary based on weather, temperature, and thickness. Check color to confirm. if it’s gray and soft to the touch it’s still wet. It should be pure white, firm to the touch turning to powder if scratched with your fingernail. To speed up dry time set up a fan blower on it. You will see the color change quickly. Even a hair dryer will work if it’s a smaller patch.

A:  When the material is dry enough so its sandable ...meaning when you sand the material with sandpaper and it creates dust, its ready for painting.

A:  The 20 lite is definitely not mold resistant, I don't think any of the fast setting compounds are resistant to mold from my experience