At what pitch does a ceiling no longer qualify as sloped?

The correct pitch at which a ceiling no longer qualifies as sloped is 2 to 12. When discussing roof configurations and ceiling slopes in the context of sprinkler fitting and fire protection measures, a slope of 2 to 12 indicates that the ceiling rises 2 units vertically for every 12 units it extends horizontally. This is a relatively low angle, and building codes or fire protection standards often define a slope as "sloped" when it is greater than this measurement.

Generally, a ceiling must have a pitch that exceeds 2 to 12 to be categorized as sloped for the purposes of installing fire protection systems like sprinklers, as it affects water distribution and pressure in fire suppression systems. A pitch of 2 to 12 is generally considered flat enough that it may not necessitate adjustments or specific considerations for sprinkler placement, thus disqualifying it as a slope that would need special attention in design or installation.