NAACOO 2 Pack Downspout Splash Block, NAACOO 24" Rain Gutter Downspout Extensions/Extender with 4pc Fixing Nails, Drainage to Protect House Foundations

Why I tried this splash block

I’ve relied on everything from concrete splash blocks to corrugated pipe to keep roof runoff away from foundations. Each approach has trade-offs: concrete is stable but heavy and awkward, and flexible tubing can look sloppy or get crushed. I put the NAACOO splash block to work on two downspouts—one at the front walkway and one beside a garden bed—to see if a lightweight, modular plastic option could provide a cleaner look without sacrificing function.

Design and build quality

This is a two-piece, interlocking splash block made of polypropylene. Assembled, it gives you roughly 24 inches of drainage path. The profile is a “ladder” style channel with a shallow 15-degree slope and a low lip along the edges to help guide water. The surface has a subtle ripple pattern that adds a bit of structure and, practically speaking, helps water sheet off rather than bead.

Build quality is better than the typical thin, flexible plastic splash blocks I’ve used. The material feels rigid without being brittle, and it didn’t warp when I left it in direct sun during a warm week. The manufacturer claims UV resistance and a 500-pound load capacity. I wouldn’t drive over it, but it didn’t flinch under my weight or a fully loaded wheelbarrow rolling across it. The finish is lightly glossy—more “utility” than “luxury”—and easy to rinse clean.

The two sections snap together with a simple tongue-and-groove, and the connection is tight enough that I had to intentionally pry them apart to separate them. There are pre-drilled holes at the top end (two per block) and four included plastic stakes for anchoring.

Setup and installation

Installation took a few minutes per downspout:

• I scraped a shallow, flat landing pad in the soil so the splash block sat flush and didn’t rock.
• I assembled the two halves and slid the upper end under the downspout by about an inch.
• I pressed in the included stakes through the pre-drilled holes at a slight angle, then tamped the surrounding soil.

On a tight side-yard where shrub roots leave little room, I used a single half instead of the full 24 inches. That modularity is handy; one piece buys you clearance in tight quarters, and the combined length gives you more runoff distance where you have room.

For a neat look on turf, I prefer to notch a thin slice of sod and seat the splash block slightly below grade. On bare soil or mulch, the black color blends in well. If you plan to place one in the middle of a bright lawn, the black will stand out more than a green option, but it’s unobtrusive near beds and foundations.

Fit and compatibility

The upper lip is low-profile enough to fit under both a standard 3x4-inch aluminum downspout and a smaller 2x3 on a shed. It also plays nicely with round corrugated extensions if you want to add length occasionally during extreme storms. Because the splash block has a defined slope built in, it still works on fairly flat ground where some cheaper, dead-flat blocks just create a puddle.

The channel depth is moderate. It’s deep enough to keep water guided even during a fast roof dump, but shallow enough that it doesn’t trap much shingle grit or leaves. The ladder ribs shed debris well; an occasional swoosh with a hose keeps it clear.

Performance in weather

I put these through two heavy afternoon thunderstorms and a few steady all-day rains. In both placements, the splash block pushed water away from the foundation, and I didn’t see the usual puddling right at the downspout. The defined slope helps: water accelerates slightly and spreads evenly across the channel rather than tracking along one edge.

One note on stability: the included plastic stakes are adequate in compacted soil and mulch. In looser, sandy soil next to my driveway, one of the blocks shifted an inch during a gusty downpour. Re-seating the stakes at a steeper opposing angle fixed it, but if you’re in very loose or sopping-wet ground, you may want to upgrade to longer landscape staples or galvanized spikes. Once anchored more firmly, the block stayed put through the next storm.

Noise and splash were minimal. Because the leading edge is not a sharp lip, water flows off without that “sheet break” splash you sometimes get with flat blocks.

Durability and maintenance

After several weeks in direct sun and a couple of temperature swings, I saw no fading, warping, or hairline cracks. Polypropylene is a good choice here—it resists UV better than cheaper polyethylene variants and feels more rigid. The surface does scuff if you drag a steel shovel across it, but the marks are cosmetic.

Clean-up is straightforward. I lifted each block, brushed away any trapped grit, and hosed it off. The ribbed design doesn’t harbor muck the way wide, cupped splash blocks do. If you winter in a freeze-thaw climate, I’d keep it slightly pitched so meltwater can’t sit and refreeze inside the channel; the piece itself should tolerate cold well.

What I liked

• Fast, fuss-free install with the option to use one or both pieces
• Rigid, UV-resistant plastic that doesn’t feel flimsy
• Built-in slope that actually moves water on flat ground
• Low-profile look that blends with soil and beds
• Pre-drilled holes and included stakes for basic anchoring
• Easy to clean; ribbed design sheds debris

What could be better

• The included stakes are on the short side for very loose or saturated soils. Longer metal stakes offer a more bombproof hold.
• The glossy finish shows scuffs more readily than a matte surface.
• At 24 inches, it’s a good general-purpose length, but if your grade slopes back toward the house, you may still want an additional extension during extreme events.

Alternatives and how this compares

• Concrete splash blocks: They stay put and feel permanent, but they’re heavy, can crack, and don’t have a built-in slope. The NAACOO unit is far easier to reposition and won’t spall.
• Flexible downspout extensions: Great for maximum reach, but they’re visually prominent and prone to flattening or clogging. The splash block is a cleaner, lower-maintenance option for day-to-day rain, with the option to add a temporary hose only when needed.
• Ultra-cheap thin plastic blocks: Inexpensive, but they tend to curl, fade, or blow away. The NAACOO’s thicker PP and staking holes are clear upgrades in usability.

Tips for best results

• Seat it on a level pad and tamp the soil; a few minutes of prep makes a big difference.
• Angle the stakes in opposite directions for a more secure hold.
• If you often mow across the area, set the block a touch below grade and support its leading edge with a thin bed of packed soil or gravel.
• For bright lawn placements, consider a green variant for aesthetics; for beds and soil, black is ideal.

The bottom line

The NAACOO splash block hits a practical middle ground: it’s more substantial and better thought-out than the bargain-bin plastic options, while sparing you the weight and hassle of concrete. The modular design is genuinely useful, the built-in slope improves performance on flat sites, and the material quality inspires confidence for long-term outdoor exposure. You may want longer stakes in challenging soils, but that’s a minor and easily solved nitpick.

Recommendation: I recommend this splash block. It’s an easy, durable upgrade that directs water effectively, installs in minutes, and looks tidy against soil and foundation beds. If you need a low-visibility, low-maintenance way to keep runoff where it belongs—especially on relatively flat grades—this is a smart pick.