Knock down ceiling is a textured drywall finishing style. It is a mottled texture, more intense than a simple flat finish, but less intense than orange peel, or popcorn, texture.
Popcorn Ceilings, more accurately a Stucco ceiling, is a term for a spray-on or paint-on ceiling treatment.
Wavy ceiling –Ceilings can appear wavy under certain lighting conditions due to light refraction. This is often a normal condition. If ceiling is wavy under natural lighting conditions at all hours of the day, an inspection would be conducted to determine if repairs are required.
Discoloration – Discoloration due to cooking, smoking or other environmental issues are exempt from warranty coverage. Discoloration due to plumbing or roof leaks will be repaired during the warranty period.