Install a rain barrel with a downspout diverter
Collect roof runoff in a closed barrel while excess water returns through a matched diverter.
Lawn & garden · 2–4 hr · Medium
Before you start
A full barrel is extremely heavy: use a flat load-bearing base, not loose stacked blocks. Secure the lid against children and pests, label water nonpotable and follow local collection rules. Wear gloves and eye protection when drilling metal; keep existing drainage away from foundations. Do not drink the water, connect it to household plumbing or leave an unsecured lid.
Tools and materials
- Purpose-made closed rain barrel, matched downspout diverter kit, hose, seals, spigot and winter cover
- Level, tape, marker, drill and kit hole saws, file, gloves, eye protection and compacted level base materials
Check the problem
Choose the location and base
Check a clear downspout run near the intended watering area. Preserve the existing overflow discharge and confirm the ground can support the full barrel without settling or tipping.
Match the diverter and barrel
Confirm downspout size, barrel inlet height and kit compatibility. This method relies on the specified inlet-to-diverter height relationship for excess water to stay in the downspout.
Steps
Prepare a stable level base
Remove soft material and build a compacted, level bearing surface suited to the filled barrel. Set the empty barrel down and check that the entire base is supported; avoid an improvised tall stand.
Fit barrel connections
Use the barrel’s factory ports when available. Otherwise drill only the kit’s marked sizes and locations; remove shavings and install seals, hose inlet and spigot exactly as specified. Tighten without distorting plastic.
Transfer the inlet height
With the barrel on its final base, transfer the barrel rim or inlet reference to the downspout with a level, then apply the exact vertical offset specified by the diverter kit. Opening-lid and permanently sealed barrels can require different heights; do not drill until this is checked.
Fit the diverter
Drill the correct downspout face and hole size, catch metal shavings and remove sharp burrs. Insert and secure the diverter in the required orientation without blocking the downspout’s main flow path.
Connect the hose and secure the lid
Seat the hose ends fully with no kink, sagging trap or rise above the diverter. Fit the lid, screen and any supplied restraint; protect every opening against insects and children. Keep the spigot accessible.
Test collection and overflow
Check seals and spigot for leaks. During a controlled test or the first rain, verify water enters and, once full, excess continues down the downspout without spilling toward the foundation. Drain and correct problems before leaving it unattended.
Check seals and spigot for leaks. During a controlled test or the first rain, verify water enters and, once full, excess continues down the downspout without spilling toward the foundation. Drain and correct problems before leaving it unattended.
Tips
Disconnect before freezing
Drain the barrel and fit the diverter’s winter closure as directed.
Not for drinking
Do not connect collected roof water to household plumbing.
Keep the path clear
Clean the gutter screen and inspect the inlet and return path regularly.