“Light-weight fixtures, followers, vents and skylights are nearly always at the bottom level. If a house incorporates a leak while in the roof or if elevated appliances like HVAC units start to leak, gravity does the rest of the do the job and delivers the water pooling into these places.” https://roofrepairing84891.shotblogs.com/the-single-best-strategy-to-use-for-roofing-contractors-47643499