How to Build a Rain Barrel for Water Conservation: A Simple DIY Guide

  • By: homeshacks
  • Date: March 26, 2023
  • Time to read: 8 min.
Affiliate Disclaimer

As an Amazon Associate, we earn from qualifying purchases.

Water conservation has become an increasingly important challenge in today’s world. With growing populations and climate change, we must all do our part to preserve this precious resource. One simple and practical way to contribute to water conservation efforts is by building a rain barrel to collect and store rainwater.

Building a rain barrel is not only beneficial for the environment, but it can also help reduce your water bill and create a sustainable way to water your plants, gardens, and lawns.

Benefits of Rain Barrels

Rain barrels offer several advantages for both the environment and homeowners. They are easy to install and maintain, making them an attractive option for water conservation efforts. Below are some of the benefits of using rain barrels:

  • Water conservation: Collecting rainwater reduces the demand on municipal water supplies and helps conserve one of our most precious resources.
  • Cost savings: By using stored rainwater for watering lawns, gardens, and household plants, homeowners can save on their water bills.

In addition to water conservation and cost savings, rain barrels also provide benefits related to stormwater management and plant health. These include:

  • Reduced runoff: Capturing water during storms helps reduce surface runoff, which can contribute to flooding and erosion. This lessens the strain on stormwater infrastructure and protects local water bodies from pollution.
  • Improved plant health: Rainwater is free of salts, minerals, and chemicals found in treated tap water. This can improve the growth and vitality of plants, making them healthier and more resistant to pests and diseases.
  • Groundwater recharge: Using rainwater for irrigation allows more water to infiltrate the soil, recharging the groundwater table and maintaining a healthy water balance in the arid and semi-arid regions.

Choosing the Right Type of Barrel

Now that you know why rain barrels are important for water conservation, it’s time to choose the right type of barrel for your project. In this section, we’ll discuss material options, size, and capacity for your rain barrel.

Material Options

There are a variety of materials to choose from when selecting a rain barrel. Some of the most common options include:

  • Plastic: Lightweight and affordable, plastic barrels are a popular choice. They are often made from recycled materials and are resistant to cracking due to cold temperatures.
  • Wood: Wooden barrels provide a more rustic and natural appearance. However, they may be heavier and less durable than their plastic counterparts.
  • Metal: Metal barrels, such as those made from steel, are durable and long-lasting but may be more expensive and prone to rusting.

Consider your aesthetic preferences, budget, and durability requirements when selecting the material for your rain barrel.

Size and Capacity

The size and capacity of your rain barrel will depend on your water collection needs and the amount of space you have available.

Common rain barrel capacities include:

CapacityApproximate Dimensions
30 gallons18″ diameter x 2′ height
50 gallons21″ diameter x 3′ height
75 gallons24″ diameter x 4′ height
100 gallons28″ diameter x 4′ height
Table showing dimensions of the number of gallons to the build size.

Keep in mind that larger rain barrels can capture and store more water, but will also require more space and may be more difficult to transport and install. Consider these factors when selecting the best size and capacity for your rain barrel.

Site Selection and Preparation

Before you start building your rain barrel, it is essential to choose an appropriate site and prepare the area for installation.


Consider the following factors when selecting the location for your rain barrel:

  • Proximity to downspouts: Your rain barrel should be near the downspout of your gutter system to effectively capture rainwater.
  • Accessibility: Ensure the chosen spot is easily accessible for maintenance and water distribution purposes.
  • Ground slope: It is best to place the rain barrel on a flat surface or an area with minimal slope to ensure stability and prevent tipping over.
  • Sun exposure: A shady area is preferable to limit algae growth and prevent the water from becoming too hot during the summer months.


A stable and level foundation is crucial for the proper installation and function of your rain barrel. Here are some steps to prepare the foundation:

  1. Measure the area: First, measure the dimensions of your rain barrel and ensure there is enough space for it.
  2. Clear the area: Remove any debris, grass, or stones within the area, so you have a clean surface to work with.
  3. Level the ground: Flatten the ground as evenly as possible using a shovel or tamping tool. This will ensure stability and reduce stress on the rain barrel when it is full.
  4. Add a base material: Once the ground is level, add a base material such as gravel or concrete pavers to provide additional support and improve drainage.

By selecting an ideal location and preparing a stable foundation, you can ensure the proper installation and the long-term success of your rain barrel.

Building the Rain Barrel

Now we will focus on assembling the various components of your rain barrel for maximum water conservation.

Creating the Inlet

First, let’s create the inlet for water to enter the barrel. Find the top center of your barrel and drill a hole that matches the size of your downspout. Then, use a wire mesh or screen to cover this hole and prevent debris from entering. Secure the mesh with a clamp or rubber gasket to ensure a firm attachment.

Building the Overflow System

An overflow system helps redirect excess water once the barrel is full. Start by drilling a hole near the top of your barrel, preferably on the opposite side of the inlet. Attach a PVC elbow fitting and a short piece of PVC pipe to the hole, sealing any gaps to prevent leakage. Ensure that the overflow pipe directs water away from your home or towards another water conservation system.

Attaching the Spigot

Now it’s time to attach the spigot at the bottom of the barrel for easy water access. Drill a hole a few inches above the barrel’s base, making sure it matches the spigot size. Use thread seal tape to wrap the spigot threads and insert it into the hole. Secure the spigot with washers and tighten the associated nuts to prevent leakage.

Securing the Lid

Finally, secure the barrel’s lid to discourage children or animals from playing in or around the barrel. Place the lid onto the barrel and use strong bungee cords or rope to hold it firmly in place. Make sure the lid is sturdy to prevent accidents.

Connecting the Rain Barrel to Your Downspout

Before connecting your rain barrel to the downspout, ensure that the barrel is level and secure on a solid base. Now, follow these steps to connect the barrel to the downspout:

  1. Measure and cut the downspout: Measure the height from the ground to the top of the rain barrel’s inlet. Mark this height on your downspout, and use a hacksaw to carefully cut the downspout. Remove any sharp edges using a file or sandpaper.
  2. Attach flexible downspout adapter: Place a flexible downspout adapter over the end of the cut downspout. Make sure it fits snugly and secure it with a metal band or a zip tie if needed.
  3. Connect adapter to the rain barrel: Position the rain barrel under the flexible adapter, ensuring the adapter is placed directly over the barrel’s inlet. Cut the adapter, if necessary, to achieve a proper fit. Keep the overflow hole or hose directed away from your home’s foundation.
  4. Secure the connection: Once you’ve connected the adapter to the rain barrel’s inlet, ensure that both the adapter and the barrel are stable and secure. You can use straps or brackets to attach the barrel to a wall for added stability.

With the rain barrel connected to your downspout, you’re ready to start collecting water for your garden, lawn, or other outdoor needs. Make sure to regularly check the connections and stability of your rain barrel, especially during heavy rainstorms.

Maintenance and Care

Regular maintenance is essential to keep your rain barrel functioning efficiently and preventing issues such as mold, algae growth, and bad odors. Follow these steps to ensure proper care of your rain barrel:

  1. Inspect for leaks: Periodically check your rain barrel for any leaks. Small leaks can be sealed using waterproof caulk or silicone sealant. For larger leaks, you may need professional assistance.
  2. Clean the filter: The filter in your rain barrel should be cleaned every few months to avoid clogging. Gently remove any debris and rinse the filter under running water. Replace the filter if it’s worn out or damaged.
  3. Treat for algae and mosquitoes: Add a few drops of non-toxic, liquid mosquito repellent and a couple of capfuls of household bleach to the rain barrel water. This will help prevent algae growth and mosquito infestation.
  4. Check the overflow: Ensure that the overflow system is unclogged and functioning correctly. This will prevent water damage to your property during heavy rains.
  5. Winterize your barrel: In colder climates, it’s essential to empty and store your rain barrel during winter to prevent freezing and damage. Disconnect the barrel from the downspout and open the spigot to let it air dry.

Proper maintenance and care will extend the life of your rain barrel and ensure that it remains an effective tool for water conservation in your home.

Safety Tips and Considerations

Building a rain barrel for water conservation is an eco-friendly and cost-effective way to collect and store rainwater. However, it is essential to consider safety measures to ensure the proper functioning of the system and avoid potential hazards. In this section, we will provide a few safety tips and considerations.

Here are some safety guidelines to follow when using a rain barrel:

  • Secure the rain barrel: Ensure that your rain barrel is placed on a flat, stable surface and is securely fastened to prevent tipping or falling.
  • Use a childproof and pet-proof lid: Install a tight-fitting, childproof and pet-proof lid to avoid accidents involving children and pets falling into the barrel. A sturdy mesh screen can also be used to prevent debris accumulation.
  • Regular maintenance: Check the rain barrel for leaks, cracks, or any signs of wear regularly. Clean it, and remove any debris from the gutters, downspouts, and filters to keep the water flowing and avoid mosquito breeding.

Additionally, consider the following points when using the collected water:

GardeningIt is safe to use rainwater for watering plants, but avoid using it on edible plants, as the water may contain contaminants.
Outdoor cleaningRainwater is suitable for cleaning outdoor surfaces, such as patios or decks. However, it may not be appropriate for washing vehicles or windows, as it can leave spots or streaks.
Indoor useRainwater collected in barrels is not suitable for drinking or cooking due to potential contamination. If considering using the water for indoor purposes, adequately treat and filter it first.

By following these safety tips and recommendations, you will be able to create a well-functioning rain barrel system that effectively conserves water while ensuring no risks for you and your surroundings.