When you see brown spots or patches on your ceiling and interior walls, they are water stains caused by a leak above. This leak could be a malfunction in your commercial roof system or a leak with another part of your facility, such as HVAC units or leaking pipes.
If there are occasions of high indoor moisture and condensation on walls you may see concentrations of brown stains running down walls in a water pattern or droplets or small brown spots where moisture accumulated on ceilings.