What are stucco buckets ?
Stucco buckets is a condition caused by water penetrating a stucco wall, and the water running into an adjoining ceiling, deteriorating the ceiling. We had this condition damage our ceilings for years until I found out what was going on.
For more details please follow the links below:
Journal of Light Construction has an excellent article about Stucco buckets here : Avoiding stucco buckets.
Here is another great article on stucco buckets on this informative site, Stuccometrics : Stucco buckets.
Here is how we avoided stucco buckets on this recently finished house.
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We drilled holes in our casing bead for weep holes.

Casing bead is dropped down about an inch and a half from the edge. This provides a drip edge so water doesn't run back on the ceiling. The face is covered with tyvek and tar paper.
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Scratch and brown.
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Finished ceiling. Water that runs down the face can't run back to the ceiling. Holes are drilled to allow water that saturates the stucco to escape.
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Finished bay window. Finish coat is white portland and white sand and is porous as a sponge. This ceiling won't fail.
Thanks so much dear readers, for reading all these years, and for all the comments.