That probably depends on what kind of valance (soffit?) but generally you can put TC fixtures within 1/2" clearance of drywall or joists. If there's room for some air to circulate around the housing, you're probably okay. NOTE: The answer changes if the valance is actually part of an attic structure (you might need air-tite or AirLoc type cans to reduce heat loss). If you have insulation present in the space, then you need to hold it back 3" on all sides from a TC or non-IC housing, build a drywall box around the housing, or get an IC housing.
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cute litte chandelier
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