Drainage Methods for Container Houses

The drainage methods for container houses mainly include two categories: organized drainage and unorganized drainage. Organized drainage can be further divided into external drainage and internal drainage. The specific methods and characteristics are as follows:

Unorganized Drainage

Unorganized drainage, also known as free drainage, refers to a drainage method where roof rainwater directly falls from the eaves to the outdoor ground. Its advantages are simple structure and low cost, without the need for a dedicated drainage pipe system. However, its drawbacks are also quite evident. The freely falling rainwater can splash and wet the walls. The foot of the exterior walls is often eroded by the splashing rainwater, affecting the durability of the exterior walls. It may also affect pedestrian traffic. Therefore, it is mainly suitable for areas with little rainfall or ordinary low-rise buildings, and not suitable for buildings on streets or high-rise buildings.

Organized Drainage - External Drainage

• Eaves Gutter External Drainage: It consists of eaves gutters, rainwater heads, and downspouts (vertical pipes). Rainwater is mostly collected by the roof eaves gutters and then flows into the downspouts arranged along the exterior walls at certain intervals, which discharge the rainwater into underground ditches or onto the ground. It is suitable for the removal of rainwater from the roofs of general residential buildings, public buildings with small roof areas, and small single-span factory buildings. The spacing of the downspouts should be determined according to the local rainstorm intensity, the roof water collection area, and the water-carrying capacity of the downspouts. Generally, a DN100 downspout is installed every 15 - 20m, with a water collection area not exceeding 250m².
• Gutter External Drainage: It utilizes the capacity and slope of the gutters formed on the roof structure to discharge rain and snow water towards both ends of the building (in the direction of the gable walls or parapet walls) and then through the vertical pipes outside the walls to the ground or rainwater pipes. It consists of gutters, rainwater heads, drainage vertical pipes, and discharge pipes. It is suitable for multi-span industrial factory buildings with a length not exceeding 100m and buildings where rainwater pipes are not allowed to be arranged inside the factory buildings.

Organized Drainage - Internal Drainage

Internal drainage consists of rainwater heads, connecting pipes, hanging pipes, vertical pipes, discharge pipes, buried main pipes, inspection wells, etc. It is suitable for large-span and multi-span buildings, buildings where it is difficult to install gutters on the roof (such as saw-tooth or shell-shaped roofs), buildings with skylights, buildings with high facade requirements, or buildings in cold regions, as well as situations where it is difficult to install vertical pipes outside the walls. However, the pipes need to pass through the roof, so proper waterproofing treatment is required. The construction is relatively complex, and pipe maintenance is inconvenient. It may also occupy indoor space.