How to Build Your Own DIY Rain Barrel: A Step-by-Step Guide to Saving Water and Money

August 25, 2025 nejc

Water is one of our most precious resources, yet millions of gallons are wasted every day through runoff from rooftops and driveways. If you’ve ever watched rainwater pour from your gutters straight into the street, you’ve probably wondered: isn’t there a better use for this?

The answer is yes. Collecting rainwater is one of the simplest, most cost-effective, and environmentally friendly ways to reduce your water bill and live more sustainably. And the best part? You don’t need an expensive setup. With just a few basic supplies and an afternoon of work, you can create your own DIY rain barrel at home.

This guide will walk you through the process step by step, offering tips, tricks, and insights along the way. By the end, you’ll not only have a functioning rain barrel but also a deeper appreciation for how small changes in your household can make a big environmental impact.

Why Collect Rainwater?

Before diving into the “how,” let’s briefly look at the “why.”

Save Money – A rain barrel can collect hundreds of gallons of free water each year, reducing your reliance on municipal water for outdoor tasks like gardening, lawn care, and washing tools.
Eco-Friendly – Rainwater collection helps reduce stormwater runoff, which often carries pollutants into rivers, lakes, and oceans. By capturing water, you’re easing the burden on local drainage systems and protecting natural ecosystems.
Perfect for Plants – Rainwater is naturally soft and free of chemicals like chlorine and fluoride, which are commonly found in tap water. Your garden and houseplants will thrive with this natural source.
Emergency Backup – Having a reserve of water can be useful in case of water restrictions, droughts, or even temporary plumbing issues.

For these reasons, DIY rain barrels have become increasingly popular among homeowners, gardeners, and eco-conscious communities.

Step 1: Gather Your Materials

Building a rain barrel may sound complicated, but it’s actually much simpler than you might think. Most of the supplies can be found at a local hardware store, and you may already have some of them at home.

Here’s what you’ll need:

One large plastic trash can (the bigger, the better; larger containers hold more water). Look for a sturdy, food-grade container if possible.
Waterproof tape or plumber’s sealant – to ensure no leaks around fittings.
Two rubber washers – these will help create a watertight seal.
One hose clamp – to secure the faucet or spigot.
One spigot (outdoor faucet) – this is where you’ll attach a watering can or hose.
A drill with hole saw attachment – to cut the opening for your spigot.
Mesh fabric (such as landscaping fabric, window screen, or agrotextile) – to cover the top and keep out leaves, insects, and debris.

Optional but useful extras:

A downspout diverter kit to connect your gutter directly to the barrel.
A small platform or cinder blocks to raise the barrel off the ground for easier access to the spigot.
Overflow hose or pipe to direct excess water away from your foundation.

Step 2: Drill the Spigot Hole

Now comes the fun part — turning your trash can into a functioning rain barrel.

Mark the spot: Choose a location on the side of the barrel near the bottom but not right at the base (leave about 2–3 inches above the ground). This ensures you can still get a container under the spigot and that sediment settling at the bottom doesn’t clog your faucet.
Drill the hole: Using your drill and the appropriately sized hole saw (slightly smaller than your spigot threading), carefully cut a hole. Go slow to keep the edges clean.
Install the spigot: Insert the spigot through the hole. On the inside, place a rubber washer against the barrel wall, followed by a nut (if your spigot comes with one). On the outside, secure it tightly with another washer and sealant tape. Tighten until snug but don’t overtighten, as plastic can crack.

Tip: If you’re unsure about sealing, wrap the spigot threads with plumber’s tape before screwing it in. This extra step helps prevent leaks.

Step 3: Create an Overflow Outlet

Rain barrels fill quickly, especially during heavy storms. Without an overflow system, excess water can spill over the sides or pool around your home’s foundation.

To prevent this, drill another hole near the top of the barrel (opposite the spigot). Insert a hose adapter and connect a short length of hose or PVC pipe to direct overflow away from your house. Some people even connect multiple barrels together in a chain, allowing overflow from one barrel to fill the next.

Step 4: Add the Top Cover

Keeping debris and insects out of your rain barrel is essential. Stagnant, uncovered water can attract mosquitoes and quickly become dirty.

Cut a piece of mesh fabric (landscaping fabric, agrotextile, or even a piece of window screen) large enough to cover the opening of your barrel. Secure it tightly under the lid or with a bungee cord. This will filter out leaves, twigs, and pests while still letting rainwater in.

If you want a cleaner system, consider purchasing a downspout diverter kit. These kits allow you to connect your home’s gutter directly to the barrel, ensuring a steady flow of water and minimizing contamination.

Step 5: Position Your Rain Barrel

Now that your rain barrel is assembled, it’s time to put it to work.

Choose the right spot: Place your barrel under a downspout where rainwater naturally flows. If needed, adjust the downspout so it empties directly onto your barrel lid or diverter system.
Elevate it: Raising the barrel on cinder blocks or a wooden platform makes it easier to fill watering cans or attach a hose. Gravity will do the work of moving water, so the higher the barrel, the better the water pressure.
Ensure stability: A full rain barrel can weigh over 400 pounds, so make sure it rests on a solid, level surface.

Step 6: Start Collecting and Using Your Rainwater

With everything in place, you’re ready to start collecting water. The first rainfall will quickly demonstrate just how effective your system is. A single inch of rain falling on a 1,000-square-foot roof can produce over 600 gallons of water — far more than most barrels can hold.

To use the water, simply open the spigot and fill your watering can or connect a hose. The collected rainwater is perfect for:

Watering gardens, lawns, and potted plants.
Washing garden tools or outdoor furniture.
Rinsing your car, bikes, or patio.

Note: While rainwater is safe for most outdoor uses, it’s not typically recommended for drinking or cooking unless properly filtered and treated.

Tips for Success

Clean your barrel regularly – Rinse it out once or twice a year to prevent algae buildup.
Check seals – Inspect washers and fittings periodically to ensure no leaks develop.
Winter care – In colder climates, empty and disconnect your barrel before freezing temperatures arrive. Ice expansion can crack plastic.
Expand your system – If one barrel fills too quickly, connect multiple barrels in series to maximize storage.

Why DIY Beats Buying Pre-Made

You can certainly buy pre-made rain barrels at garden centers or online, but making your own has several advantages:

Cost savings: DIY barrels often cost a fraction of commercial ones.
Customization: You control the size, color, and features to match your needs.
Satisfaction: There’s something rewarding about building a system yourself and seeing it work.

Plus, the process is simple enough that anyone can do it — no plumbing expertise required.

Closing Thoughts

Rainwater collection is one of those rare projects that checks every box: it saves money, helps the environment, supports your garden, and gives you a sense of accomplishment. By following the steps above, you can build a durable, functional rain barrel with just a few tools and materials.

The next time it rains, instead of watching water pour uselessly from your gutters, you’ll know it’s being captured, stored, and put to good use. Small steps like this not only make your home more sustainable but also connect you more closely to the natural cycles around you.

So grab that drill, find a sturdy trash can, and start building — your garden (and your wallet) will thank you.

WCH

WCH