A rain barrel collects and stores rainwater runoff captured from a home’s roof via its gutter system. The stored water is non-potable, meaning it is not suitable for drinking, but it is perfectly suited for uses such as garden irrigation. Using a rain barrel reduces household water consumption, which can lead to lower water bills and lessen strain on municipal water resources.
Selecting and Preparing the Container
The primary container should prioritize material safety and light exclusion to maintain water quality. A 55-gallon drum is a common choice, constructed from food-grade plastic, typically High-Density Polyethylene (HDPE). The container must also be opaque and ideally dark in color, as this prevents sunlight penetration and inhibits algae growth.
Before any modifications are made, the barrel requires thorough cleaning to remove any residual substances from its previous contents. Even if the barrel is rated food-grade, a comprehensive rinse is necessary to ensure the water will be clean for non-potable uses. A mild solution of dish soap or a diluted bleach solution can be used to scrub the interior, followed by multiple rinses with clean water. This preparation step is important to eliminate any lingering odors or trace contaminants that could affect the quality of the harvested rainwater.
Necessary Hardware and Tools
A durable spigot, often a brass or plastic hose bib, is needed at the bottom to control the water flow for garden hoses or watering cans. Watertight connections are achieved using specialized bulkhead fittings, which include rubber washers and nuts designed to seal the connections against the curved surface of the barrel.
An overflow port, often constructed from a PVC elbow or adapter, is necessary near the top to prevent flooding once the barrel is full. To prevent the entry of insects, particularly mosquitoes which breed in standing water, and to filter out large debris, a fine mesh screen must be acquired. The necessary tools for modification include a power drill, a hole saw sized appropriately for the fittings, and a quality exterior-grade sealant, such as silicone caulk, for permanent sealing.
Barrel Modification and Assembly Steps
The physical assembly begins with precisely marking and drilling the three required openings in the barrel. The spigot hole must be placed near the bottom, typically one to two inches from the base, to maximize water draw-down and leverage gravity for pressure. A second hole for the overflow port is positioned near the top rim, ensuring that excess water is redirected before the barrel overflows. Finally, an inlet hole is cut into the top lid of the barrel to receive the water from the downspout system.
Once the holes are drilled, the bulkhead fittings are installed, securing the spigot and the overflow adapter to the barrel wall. This often involves inserting the fitting from the outside and tightening the nut and washer from the inside to compress the rubber gasket for a leak-proof seal. A bead of silicone sealant should be applied around the exterior flange of each fitting before final tightening to enhance the water barrier. The spigot is then attached to the lower bulkhead fitting, which should be done carefully to avoid stripping the plastic threads.
The mesh screen is then secured over the inlet hole on the lid. For barrels with removable lids, the entire lid can be modified, or a smaller hole can be cut and the screen secured over it using an adhesive or a retention ring. Allowing the sealant on all connections to cure for a full 24 hours before filling the barrel is recommended to ensure long-term stability and prevent premature leaks.
Site Preparation and Downspout Connection
Proper site preparation is necessary due to the significant weight of a full water container, which demands a robust and level foundation. A standard 55-gallon barrel filled with water weighs approximately 480 pounds, requiring the base to be stable enough to support this concentrated load. The barrel should be placed on a solid platform, such as stacked concrete blocks or a concrete paver slab, to ensure stability and to elevate the spigot for easier access and better water pressure.
Connecting the barrel to the gutter downspout can be accomplished using one of two primary methods. Regardless of the connection method chosen, it is important to ensure that the overflow port is directed safely away from the home’s foundation. Directing overflow water several feet away prevents saturation and potential damage to the structure’s base.
Direct Cut Method
The simpler approach involves cutting the downspout above the barrel and routing it directly into the screened inlet hole on the lid. This method ensures all captured water flows directly into the barrel.
Downspout Diverter Kit
A more controlled approach uses a downspout diverter kit, which is installed into a section of the downspout. The diverter automatically channels rainwater into the barrel via a flexible hose until the barrel is full, at which point a float or internal mechanism redirects the excess flow back down the original downspout.