What to Put Underneath an Above Ground Pool: Complete Guide

what to put underneath an above ground pool

Are you excited about setting up your new above-ground pool but wondering about the foundation?

Knowing what to put underneath an above ground pool is crucial for its stability and longevity. We're here to guide you through choosing the perfect base material for your pool.

Think of your pool base like the foundation of a house - it needs to be solid, level, and properly prepared. Let's explore the best materials and methods to create the perfect foundation for your summer oasis.

Understanding Base Requirements

According to the Association of Pool & Spa Professionals, proper base materials must provide:

  • Level surface

  • Cushioning

  • Drainage

  • Protection from sharp objects

  • Stability

Best Base Material Options

1. Commercial Padding

Benefits of commercial pool pads:

  • Pre-made for pools

  • Consistent thickness

  • Easy installation

  • Excellent protection

  • Professional quality

  • UV-resistant

  • Warranty protection

  • Chemical resistant

Types available:

  • Geotextile fabric

  • Armor shield padding

  • Gorilla padding

  • Blue armor padding

  • Rhino padding

2. Sand

What to know about sand bases:

  • Inexpensive option

  • Natural drainage

  • Easy to level

  • Readily available

  • 2-inch minimum depth

  • Multiple grades available

  • Good compression properties

  • Traditional choice

Best sand types:

  • Mason sand

  • Pool sand

  • Concrete sand

  • Silica sand

  • River sand

3. Solid Foam

Advantages of foam bases:

  • Excellent insulation

  • Shock absorption

  • Moisture resistant

  • Easy to cut

  • Durable protection

  • Temperature stable

  • Prevents ground freezing

  • Chemical resistant

Available forms:

  • Closed-cell foam

  • Expanded polystyrene

  • Extruded polystyrene

  • Custom-cut panels

  • Interlocking tiles

Installation Process Deep Dive

1. Site Assessment

Before installation begins:

  • Measure area dimensions

  • Check ground slope

  • Test soil composition

  • Identify drainage patterns

  • Mark utility locations

  • Note sun exposure

  • Check local regulations

  • Document existing conditions

2. Ground Preparation

Proper preparation steps:

Remove Vegetation

  • Clear all grass

  • Remove root systems

  • Apply herbicide if needed

  • Wait for soil settling

Level the Ground

  • Use transit level

  • Create slope guide

  • Remove high spots

  • Fill low areas

  • Check multiple points

  • Document measurements

Soil Preparation

  • Remove debris

  • Till if necessary

  • Add fill if needed

  • Compact thoroughly

  • Test stability

  • Check moisture content

Final Checks

  • Verify measurements

  • Double-check level

  • Test drainage

  • Document conditions

  • Take photos

  • Mark reference points

Material Comparison

Cost Analysis

Compare options (per 100 square feet):

  • Commercial pad: $100-200

  • Sand: $30-50

  • Solid foam: $150-300

  • Crushed stone: $40-60

Durability Ratings

Expected lifespan:

  • Commercial pad: 7-10 years

  • Sand: 3-5 years

  • Solid foam: 5-8 years

  • Crushed stone: 10+ years

Important Considerations

When deciding what do you put underneath an above ground pool, consider:

  • Local climate

  • Soil type

  • Budget

  • Pool size

  • Installation timeline

  • Local regulations

Common Mistakes to Avoid

Don't make these errors:

  • Insufficient ground preparation

  • Using wrong material thickness

  • Skipping proper leveling

  • Inadequate drainage planning

  • Mixing incompatible materials

Advanced Installation Tips

Working with Slopes

Key considerations for sloped terrain:

Slope Assessment

  • Measure slope angle

  • Calculate elevation change

  • Determine drainage patterns

  • Plan retaining walls

  • Consider erosion control

Support Systems

  • Plan buttress placement

  • Design reinforcement

  • Select materials carefully

  • Include drainage systems

  • Monitor stability

Special Materials

  • Use reinforced bases

  • Add stabilization layers

  • Include erosion barriers

  • Plan water management

  • Consider soil retention

Dealing with Problem Soils

Solutions for challenging ground:

Clay Soil

  • Add drainage layers

  • Use soil amendments

  • Include sand layers

  • Plan water management

  • Monitor moisture levels

Sandy Soil

  • Add stabilization

  • Use geotextile fabric

  • Include compaction

  • Plan edge retention

  • Monitor settling

Rocky Ground

  • Remove large rocks

  • Add cushioning layers

  • Use protective barriers

  • Plan drainage carefully

  • Monitor pressure points

Maintenance Tips

Keep your base in good condition:

  • Check levelness annually

  • Address settling promptly

  • Maintain proper drainage

  • Replace damaged materials

  • Monitor for erosion

Climate Considerations

Adapt to your environment:

Hot Climates

  • Use heat-resistant materials

  • Ensure proper ventilation

  • Consider moisture barriers

  • Monitor for drying/cracking

Cold Climates

  • Choose freeze-resistant materials

  • Plan for winter protection

  • Consider insulation needs

  • Monitor for frost heave

Professional vs. DIY

Consider these factors:

  • Project size

  • Available time

  • Equipment needs

  • Skill level

  • Budget constraints

  • Local requirements

Required Tools

Gather these items:

  • Shovel

  • Level

  • Rake

  • Tamper

  • Measuring tape

  • String line

  • Stakes

  • Safety gear

Safety Considerations

Important precautions:

  • Check utilities before digging

  • Wear proper safety gear

  • Use appropriate tools

  • Follow local codes

  • Document installation

  • Consider drainage impact

Conclusion

Choosing what to put underneath an above ground pool is a crucial decision that affects your pool's stability and longevity. By following these guidelines and selecting the right materials, you'll create a solid foundation for years of summer fun.

Want more pool installation tips? Check out our other helpful guides for maintaining your backyard oasis!

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