What type of strainer should be used on roofs where leaves and debris may accumulate?

Mushroom strainers are particularly effective on roofs where leaves and debris may accumulate due to their design. They feature a dome-shaped cover that allows water to flow into the strainer while preventing larger debris, such as leaves, from entering the drainage system. This design not only helps maintain an effective water flow but also reduces the likelihood of clogs caused by the accumulation of organic material.

In contrast, flat strainers do not provide any elevation or barrier to large debris, making them less suitable for scenarios with heavy leaf litter. Perforated strainers may allow smaller debris to pass through, which increases the risk of clogging over time. Grated strainers, while they can prevent some debris from entering, often lack the effective coverage and water-collection capacity that mushroom strainers offer. Thus, mushroom strainers stand out as the best option for maintaining roof drainage in areas prone to debris accumulation.