Coil Load & SHR
A cooling coil does two jobs at once and they cost very different amounts. Dropping the temperature is cheap; wringing water out is not. The sensible heat ratio is the split, and it is why a system sized purely on temperature can leave a room cold and clammy.
Leaving air off a wet coil is typically 90–95% RH, not 100% — some air slips through untouched, which is what the coil bypass factor describes. Positive values are cooling; a leaving state warmer than entering simply reads negative. Airflow is taken at the entering condition.
Design-stage estimates. A real project needs a full load calculation to the ASHRAE/CIBSE procedure, and ventilation rates are code-mandated — check the standard and jurisdiction that apply to your building. A helper, not a substitute for engineering judgment.