A. Ron Webber, owner of Prime Plastering in Irvine, Calif., responds: Applying new stucco over old stucco (often called re-stuccoing) is a fairly simple-process. If the existing wall is in good condition, this job can be straightforward. But if the existing surface has imperfections, the problems that caused the flaws must be repaired, or else the problems will recur. Before re-stuccoing, thoroughly examine the existing surface and ask the following questions:
Is there any loose, spalling stucco? Rub and tap the wall, listening for hollow sounds. Any loose stucco will need to be removed by scraping or sandblasting. To patch the stucco, combine sand and cement with calcium aluminate, an accelerator, or use a good nonshrinking stucco patching material or a rapid-set mortar mix.
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