An existing building with an existing sprinkler system is constructed with 26 in.

When using standard upright sprinklers with beams framed into girders spaced on 7 ft centers, a maximum distance of 12 in. below the ceiling or roof deck is typically permitted. This ensures the sprinklers maintain effective coverage while accommodating architectural features.

References: NFPA 13 installation standards for upright sprinklers in relation to ceiling obstructions and beam configurations.