You can install a rain barrel in one weekend afternoon for under $100, with basic hand tools and no plumbing experience. Pick a downspout, raise the barrel on a level stand, cut the downspout, fit a diverter, add spigot and overflow hose, then fill it and check for leaks. Plan on two to three hours, including the hardware-store trip.
Parts List: Everything You Need for Under $100
Prices are approximate US hardware-store prices. A food-grade 55-gallon drum is the cheapest barrel; purpose-built rain barrels cost more but come with spigot and screen fitted.
| Part | Approx. price |
|---|---|
| Used food-grade 55-gal drum | $25–$40 |
| Downspout diverter kit | $15–$25 |
| Brass spigot (¾ in) + washers | $8–$12 |
| Overflow hose, 4–6 ft | $5–$8 |
| Fine mesh screen | $3–$5 |
| Stand: 4 concrete blocks or lumber | $8–$12 |
| Teflon tape, screws, sealant | $3–$5 |
| Total | ~$67–$107 |
If the total creeps over $100, the barrel is the culprit — a used food-grade drum at $25 keeps the project under budget, while a decorative barrel can cost $60–$90 on its own.
Tools You Will Need
Drill and bits (hole saw or spade bit for the spigot and diverter), hacksaw or tin snips, tape measure, spirit level, adjustable wrench, screwdriver, silicone sealant or plumber’s tape, gloves, and safety glasses.
Step 1: Choose a Downspout Spot
Pick a downspout serving a good stretch of roof, near the beds you want to water. Check three things:
- Ground that can take weight. A full 55-gallon barrel weighs about 460 pounds (55 gal × 8.34 lb per gallon). The ground under the stand must be firm and level.
- Clearance above. You need room to lift the barrel onto the stand and open the lid.
- A place for overflow to go. The overflow hose needs a downhill path to a bed, lawn, or drain — not against the foundation.
Step 2: Build a Level, Sturdy Stand
The stand raises the barrel high enough to fit a watering can under the spigot and creates the gravity pressure that makes a soaker hose work. Aim for 18–24 inches. Four concrete blocks (two stacked on each side) or a simple frame of treated 2×4 lumber both work.
Whatever you build, it must be level and sturdy — remember the 460-pound figure. A stand that tilts when full dumps a barrel of water against your foundation. Check it with a spirit level in both directions, then load-test it: set the empty barrel on it and push firmly from several angles. If it rocks, shim it or rebuild it.
Step 3: Cut the Downspout and Fit the Diverter
A downspout diverter sits in the downspout, catches rainwater flowing down, and channels it sideways into the barrel. When the barrel is full, the diverter lets excess water continue down the downspout.
- Mark the cut line at the height of the barrel’s inlet — usually just below the top of the barrel.
- Cut with a hacksaw or tin snips, keeping the cut square. Keep the offcut.
- Fit the diverter into the gap, following the kit’s instructions, and seal the joints.
- Connect the diverter’s outlet hose to the barrel’s inlet and secure it with a hose clamp.
Step 4: Fit the Spigot and the Overflow
Spigot. Drill the hole 3–4 inches above the bottom of the barrel — low enough to drain almost all the water, high enough to clear the stand. Fit the spigot with its washers, wrap the threads with Teflon tape, and tighten by hand plus a quarter turn. Overtightening cracks plastic drums.
Overflow. Drill a second hole near the top of the barrel, on the side facing away from the house, and fit the overflow hose. Route it downhill to a bed, lawn, or drain at least 3–4 feet from the foundation. Without it, a full barrel in a heavy storm spills down its side and pools against the house.
Screen. Cover every opening — inlet and lid — with fine mesh screen. This is mosquito and debris control in one step.
Step 5: First Fill and Leak Check
- Close the spigot and make sure the diverter is open.
- Wait for rain, or fill the barrel with a garden hose to test.
- Watch every joint — spigot, diverter, overflow, lid — for the first 15 minutes.
- Tighten or re-seal anything that weeps. A slow drip at the spigot is usually a washer seated crookedly; re-seat it.
- Once full, open the spigot into a bucket and confirm steady flow.
Common Mistakes (and How to Avoid Them)
| Mistake | What goes wrong | Fix |
|---|---|---|
| Stand not level or too weak | Barrel tilts or topples at ~460 lb | Level both ways, load-test first |
| No overflow hose | Full barrel floods the foundation | Overflow near the top, routed downhill |
| Spigot too low or high | No room for a bucket, or gallons stranded | 3–4 in above the bottom, stand 18–24 in |
| No screen on openings | Mosquitoes breed, leaves clog the diverter | Fine mesh on every opening |
| Downspout cut wrong | Diverter hose kinks or won’t reach | Measure from the barrel inlet |
| Overtightened spigot | Cracked drum, permanent leak | Hand-tight plus a quarter turn |
Safety Notes
Water is heavy, and this project is mostly weight management. A full 55-gallon barrel weighs about 460 pounds — roughly two adults. Keep children clear while moving or filling the barrel, never climb on the stand, and if the barrel starts to lean, step back and let it fall rather than trying to catch it.
FAQ
Barrel water is for ornamental gardens, lawns, and outdoor cleaning only — not drinking, and not for plants you plan to eat. The CDC recommends tap or bottled water for those uses.
How long does it take to install a rain barrel?
Two to three hours for a first install, including the hardware-store trip. The downspout cut and the stand take most of that time.
Can I install a rain barrel without a diverter?
You can route the whole downspout into the barrel, but a diverter is worth the $15–$25: it stops overfilling and makes winter disconnection easy.
How high should the rain barrel stand be?
18–24 inches — high enough to fit a watering can under the spigot, giving roughly 0.8–1 psi of gravity pressure, enough for a short soaker hose.
Leave a Reply