Where should roof drainage be installed unless roofs slope to drain over roof edges?

Roof drainage needs to be effectively managed to prevent water accumulation and potential damage to the roofing structure. When roofs do not have a sufficient slope to allow water to naturally flow off the edges, proper placement of drainage systems becomes critical.

Installing drainage at each low point of the roof is essential because these areas are where water will naturally collect due to gravity. In flat or low-slope roofs, water tends to pool in low areas; therefore, positioning drainage systems at these points helps facilitate the timely removal of water and reduces the risk of leaks, structural damage, and potential mold growth.

Effective drainage is also vital for adhering to building codes and standards that are designed to ensure the safety and longevity of the structure. This approach minimizes the need for additional water management techniques and promotes the efficient use of the roofing system, reducing maintenance issues.

In contrast, placing drainage at the highest points or along the ridge would not effectively address water accumulation since these points do not collect water. Similarly, distributing drainage along each side of the roof does not guarantee that water at the low points would be managed appropriately. Thus, focusing drainage solutions at each low point remains the most effective and practical strategy for managing roof drainage.