It can be extremely frustrating to finish construction on a new deck, only to realize later on that the deck drainage system is insufficient to properly control the rain flow. Drains are an important element of deck design and construction, and under-deck drainage is critical in keeping the surface dry and free of water damage. Read on to see some of the most common deck drainage mistakes and how to avoid them.
1. Select Inefficient Channels
As rain washes plant matter and dirt off of the deck surface, leaves and other debris can become stuck in a drainage channel. If too much material becomes lodged in the channel, the drainage system becomes clogged and either overflows or breaks.
Square channels are the most likely to catch debris. Instead of a rectangular-shaped drainage system, select tunnels that are rounded or that have v-shaped channels. These promote consistent water flow, which in turn helps to keep your drainage system free of debris.
2. Choose the Wrong Drain for Your Water Flow
Some decks receive only a trace amount of water each year, while others may see many inches of rain each month. Drainage systems are not all designed to accommodate the same amount of water, and some systems will malfunction if installed in a deck that experiences large amounts of rainfall. Multi-channel systems can help to divert high quantities of water while simultaneously offering insurance against a chance malfunction in one channel.
3. Install a Weak Drainage System
Deck drainage systems must be made of material that can withstand extreme temperature changes, heavy and consistent water flow, and other types of exposure. Certain types of metal drain systems will corrode or rust over time. These systems are ineffective for decks that receive even a moderate level of rainfall. Furthermore, the water that flows through these systems becomes tainted and potentially poisonous to animals and children.
For best results, select a drainage system made from thick PVC pipe or plastic. These materials do not dissolve or diminish in quality over time, and likewise they will not contaminate the water that flows through them.
4. Poorly Direct the Water
A proper deck drainage system removes the water from your deck without transferring all the water to a single location. By dumping large quantities of water in one location, you increase the risk of erosion or other landscape damage, as well as of pooling and damage to buildings.
Rather, ensure your drainage system promotes a level, even water flow by maintaining a constant downward grade. Use branched channels to redirect water to multiple areas. Clever deck builders install drainage systems that collect water in convenient places for lawn and garden use. This can reduce environmental waste and cut down on irrigation costs.