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title: Suspended Acoustical Ceilings
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## Acoustical panels are routinely damaged, stained by plumbing leaks, and removed for plenum access over the life of a building, and the panel finish and shade are difficult to match exactly with later production, so attic stock from the original lot ensures that replacements match the installed ceiling; a 2 percent attic stock is a reasonable default, and spaces with frequent plenum access or higher exposure to leaks warrant more. {note}