Last updated: July 2026
To level ground for an above ground pool: mark the footprint, measure the slope, remove all grass and vegetation, excavate the high side down to match the low side, rake 1–2 inches of play sand as the final leveling layer, and check level again before installing the pool. Never build up the low side with fill — fill soil compresses unevenly under water weight.
The full process takes 2–5 hours for a 15ft pool on a mild slope, longer for larger pools or steeper grades. Here’s exactly how to do it correctly.
What You’ll Need
| Tool / Material | Purpose | Where to Get It | Approx. Cost |
|---|---|---|---|
| 4–6 ft spirit level (or line level + string) | Measure slope across pool footprint | Hardware store | $15–40 |
| Measuring tape | Mark pool footprint and measure elevation change | Any hardware store | $10–25 |
| Marking spray paint or stakes + string | Mark pool footprint perimeter | Hardware store | $5–15 |
| Flat spade shovel | Remove sod and excavate high side | Hardware store | $25–60 |
| Garden rake | Smooth and level the final sand layer | Hardware store | $15–35 |
| Play sand (washed) | Final 1–2 inch leveling layer | Hardware store / landscape supplier | $5–15 per 50 lb bag |
| Wheelbarrow (optional) | Move excavated soil | Hardware store | $60–150 or rent |
| Pool pad / ground cloth | Protect liner from ground | Amazon / pool retailer | $20–50 |
| Tamper (optional) | Compact sand layer | Hardware store or rent | $30–100 or rent |
For a 10–12ft pool on a mild slope, a shovel, rake, level, and 2–3 bags of play sand is all you need. For larger pools or steeper slopes, add a wheelbarrow and consider renting a plate compactor for the final sand layer.
Step 1: Measure Your Slope
Before moving any soil, measure exactly how much slope you’re dealing with. This determines whether DIY leveling is realistic or whether you need professional help.
- Place a stake at the centre of your planned pool location.
- Tie a string from the stake to a second stake at the edge of the pool footprint.
- Hold a line level on the string and adjust the string until it reads perfectly level.
- Measure the distance from the string to the ground at the edge stake. This is your slope elevation difference across the pool radius.
- Double this number to get the slope across the full diameter.
| Total Slope Across Diameter | DIY Feasibility | Method Required |
|---|---|---|
| 0–1 inch | Easy DIY | Sand leveling only — rake and sand |
| 1–2 inches | Standard DIY | Remove sod + excavate slightly + sand layer |
| 2–3 inches | Hard DIY (half-day work) | Significant excavation of high side + sand layer |
| 3–4 inches | Consider hiring out | Substantial excavation; wheelbarrow required |
| 4+ inches | Hire a landscaper | Beyond practical DIY — professional grading recommended |
Step 2: Mark the Pool Footprint
- Find the centre point of your pool location. Drive a stake here.
- Tie a string to the stake equal to the pool’s radius (half the diameter). For a 15ft pool, this is 7.5ft.
- Walk the string in a circle, marking the ground with spray paint every few feet. This gives you the pool’s exact perimeter.
- Add 6 inches beyond the perimeter mark — this is your working area for leveling.
| Footprint sizes to mark by pool diameter 10ft pool: mark a circle 5ft from centre stake (10ft diameter) 12ft pool: mark a circle 6ft from centre stake (12ft diameter) 15ft pool: mark a circle 7.5ft from centre stake (15ft diameter) 18ft pool: mark a circle 9ft from centre stake (18ft diameter) Add 6 inches beyond the marked circle for your working/leveling zone |
Step 3: Remove All Grass and Vegetation
This step cannot be skipped. Grass and vegetation beneath a pool liner compress unevenly under water weight, creating soft spots and pressure points that cause premature liner puncture.
- Use a flat spade to cut through the sod in 12–18 inch sections within the marked footprint.
- Lift and remove each sod section completely. Don’t leave roots or grass clumps in place.
- Remove any rocks, roots, or debris visible in the exposed soil.
- Inspect for any buried rocks or roots at 2–4 inches depth by probing with the spade. Remove anything sharp or protruding.
| ⚠️ Common mistake: skipping sod removal Laying a pool directly on grass — even with a ground cloth — allows the grass to decompose under the pool. Decomposing vegetation creates soft spots that shift under water weight. This unevenness stresses the liner and frame. Grass also continues growing under the pool if not removed, eventually pushing through the ground cloth. Always remove the full sod layer before leveling. |
Step 4: Excavate the High Side Down
This is the most important rule of pool leveling: always cut the high side down. Never build up the low side with fill dirt.
Fill dirt — no matter how well compacted — compresses gradually under the weight of thousands of gallons of water. An 18ft pool holds over 7,600 gallons — that’s over 63,000 lbs of water weight. Filled soil that shifts even half an inch under that weight will cause the pool frame to stress and the liner to pull unevenly.
- Identify the high point of your leveling area. This is the point your string-level exercise showed as highest.
- Using the low point as your target depth, excavate soil from the high side until the ground across the full footprint matches that depth.
- Work in sections — excavate a strip, check with your level, excavate more as needed.
- Move excavated soil away from the pool area immediately. Don’t pile it at the edge where it can slump back in.
Step 5: Rake and Compact the Base
- Once the high side is cut down to match the low side, use a garden rake to smooth the exposed soil across the full footprint.
- Remove any remaining small rocks, roots, or debris uncovered during excavation.
- If you have access to a plate compactor (rental: $50–100/day): make 2–3 passes across the leveled soil to compact it. This reduces settling under load.
- If no compactor: tamp the soil manually with the back of your shovel or a hand tamper. Less effective than a plate compactor but adequate for smaller pools (12ft and under).
Step 6: Add the Sand Layer
Play sand (also called washed sand or pool base sand) is the final leveling layer. It fills in minor irregularities in the excavated base and provides a smooth, protective surface for the ground cloth and liner.
- Spread play sand evenly across the leveled footprint to a depth of 1–2 inches.
- Rake it flat and smooth — no bumps, no ridges.
- Check level across the full footprint one final time with your long spirit level or line level. Check in at least four directions (north-south, east-west, and two diagonals).
- Any remaining high spots: remove sand from those areas. Any low spots: add a bit more sand and re-rake. The target is within ½ inch of level across the full pool base.
| 💡 Sand type matters: use play sand, not builder’s sand Play sand (washed river sand): fine, smooth, consistent grain size. Compacts well and stays flat under load. Correct choice. Builder’s sand (coarse/sharp sand): irregular grain size, sharper particles. Can puncture liners over time and doesn’t compact as evenly. Wrong choice. Paver sand: similar issues to builder’s sand. Wrong choice. How much play sand to buy: roughly 0.5–1 cubic foot per square foot of pool base area at 1 inch depth. A 15ft pool base is ~177 sq ft, so ~10–18 cubic feet (5–9 bags of 50 lb play sand). |
Step 7: Lay the Ground Cloth and Install the Pool
- Lay the included ground cloth (or foam pool pad) on the leveled sand base. Centre it within the pool footprint.
- If using a foam pad in addition to the ground cloth: pad goes down first, then ground cloth on top.
- Begin pool frame assembly on the leveled base according to the pool’s instruction manual.
- Before filling with water: check once more that the assembled frame is level. Use a level on the top rail in at least four positions around the pool.
- Fill slowly for the first 6–12 inches and check again. Water weight is the final test of your leveling work — if the pool lists to one side as it fills, stop filling and re-level before continuing.
When to Hire a Professional
DIY leveling is realistic for slopes up to about 3 inches across the pool footprint on a 12–15ft pool. Beyond that, the work becomes either physically demanding enough to require equipment rental, or complex enough to risk an incorrect result that causes pool failure.
| Situation | DIY or Hire? | Estimated Cost |
|---|---|---|
| 0–2 inch slope, 10–15ft pool | DIY | $20–80 (sand + materials) |
| 2–3 inch slope, 15ft pool | DIY (with effort) | $40–120 (sand + tools) |
| 3+ inch slope, 15ft pool | Consider hiring | $300–600 (landscaper) |
| Any slope, 18ft+ pool | Professional recommended | $400–800 |
| Rocky or clay soil needing excavation equipment | Hire out | $400–1,200+ |
| Doughboy Pioneer or premium resin frame install | Professional install | $500–1,000+ |
Common Mistakes to Avoid
- Building up the low side with fill: always excavate the high side down instead. Fill compresses.
- Using the wrong sand: builder’s sand has sharp particles that can puncture liners. Only use play sand (washed river sand).
- Skipping the level check after adding sand: the sand layer can introduce new unevenness. Always re-check after raking.
- Leaving any grass or roots in the footprint: they decompose and shift under load.
- Installing on wet ground: wait until the soil is dry enough to compact properly. Wet clay soil in particular will settle unevenly as it dries.
- Only checking level in one direction: check in at least four directions (N-S, E-W, and both diagonals). A pool can be level east-west but not north-south.
Frequently Asked Questions
How level does the ground need to be for an above ground pool?
Within 1–2 inches of level across the full pool diameter is the standard target. The closer to perfectly level, the better — but most pools tolerate up to 2 inches of residual variation after leveling without significant problems. Beyond 2 inches of slope, frame stress and uneven liner loading become serious concerns.
Can I use pea gravel instead of sand under my above ground pool?
No. Pea gravel does not compact properly and the rounded stones can shift under load, creating uneven pressure points under the liner. Play sand is the correct material for the final leveling layer. If you need drainage improvement under the pool area, address that with the soil base before adding sand — don’t use gravel as a sand substitute.
How long does it take to level ground for an above ground pool?
For a 12–15ft pool on a mild slope (1–2 inches): 2–4 hours with two adults. For an 18ft pool on a moderate slope (2–3 inches): a full day with two adults and possibly a wheelbarrow. For larger slopes or bigger pools, plan for professional help that takes 1–2 days.
Do I need to remove grass before putting up an above ground pool?
Yes — always. Grass left under the pool decomposes, creates soft spots, and continues growing under the liner. Even with a ground cloth, grass must be fully removed before the pool base is prepared. Removing the sod takes 30–60 minutes for a 12ft pool and 1–2 hours for a 15–18ft pool.
What happens if the ground is not level under an above ground pool?
An unlevel base causes the frame to stress unevenly at joints and connectors, the liner to pull toward the low side (creating pressure on bottom seams and drain fittings), and in severe cases, the pool to collapse sideways. Even a 3–4 inch slope that’s not corrected can cause structural failure within one season. Leveling correctly before setup is the single most important step in above ground pool installation.
Can I put an above ground pool on concrete?
Yes — concrete is an excellent pool base if it’s flat and level. You still need a foam pool pad between the concrete and the liner to protect against abrasion and temperature extremes. If the concrete slopes (as many patios do for drainage), you need to choose a pool size that fits within a level section, or the slope problem is the same as for any other surface.