What Is a Sleep Number Mattress Made Of? Materials, Layers, and Comfort Explained

If you’re searching “What Is a Sleep Number Mattress Made Of”, you’re likely trying to understand what’s inside these adjustable beds, how they feel, and whether the materials match your comfort and durability expectations. This breakdown focuses on the typical components and how they affect your sleep experience.

What Is a Sleep Number Mattress Made Of?

At its core, a Sleep Number–style air bed is generally made of three main elements:

An air chamber system that adjusts firmness
Comfort layers on top (usually foam-based)
An outer cover and support structure (base and edging)

Each part plays a different role in how the mattress feels, wears over time, and responds to your body.

The Air Chambers: The “Support Core” of the Mattress

What are the air chambers made of?

The support system usually consists of flexible, reinforced air bladders made from durable synthetic materials, often a type of vinyl or similar polymer designed to hold air without leaking. These chambers:

Inflate or deflate to change firmness
Are divided by side on many models so each sleeper can choose their own setting
Connect to a small air pump that is often controlled electronically

How do the air chambers affect comfort?

The air chambers mainly influence:

Firmness and support: More air usually means a firmer feel; less air gives a softer, more compressible feel.
Pressure distribution: Adjustments can help some sleepers find a position that feels more evenly supported.

While the chambers themselves are not plush or cushiony, they act as the adjustable backbone of the mattress.

Comfort Layers: Foams and Cushioning on Top

What are the comfort layers usually made of?

On top of the air chambers, there are typically foam comfort layers. These may include:

Polyurethane foam: A common base foam used for cushioning and structure.
Memory foam–type materials: Designed to contour more closely to the body.
Specialty foams or fiber layers: Sometimes included for extra softness, airflow, or targeted support.

The exact mix and thickness varies by model, which is why different adjustable-air mattresses can feel more firm, plush, or contouring even though they all use air inside.

How do these foams affect how the mattress feels?

The comfort layers largely determine:

Initial softness when you first lie down
Pressure relief around shoulders, hips, and joints
Motion feel, such as how much you notice your partner moving

Many sleepers who like the adjustability of air prefer a mattress with enough foam on top to reduce the feeling of lying directly on an air chamber.

Outer Cover and Edge Structure

What is the cover made of?

The outer cover is usually a quilted fabric encasement, often made from:

Polyester or polyester blends for durability and stretch
Knit or woven fabrics that allow some airflow
Light fiberfill or quilting foam for a cushioned surface feel

The cover helps with:

Temperature feel at the surface (breathability varies by fabric type)
Overall smoothness and appearance of the bed
Keeping internal layers held in place

What about the edges and base?

Around the perimeter and below the air chambers, you’ll often find:

High-density foam rails: These help keep the mattress shape and can make the edge feel more stable.
A fabric or platform base: Designed to hold the air system and foams securely and connect to the pump and controls.

These structural elements don’t often change how the mattress feels at the center but can affect edge sitting, shape, and long-term support.

Why Do These Materials Matter for Comfort and Sleep Issues?

Understanding what a Sleep Number–style mattress is made of helps you predict how it might work for your body and preferences:

Adjustability: Because the core is air-based, you can fine-tune firmness more easily than with a traditional spring or solid foam mattress.
Pressure relief: The foam types and thicknesses on top matter a lot if you’re sensitive at shoulders, hips, or lower back.
Temperature feel: Thick foam layers and certain fabrics may feel warmer to some sleepers, while more breathable covers and less dense foams may feel cooler.
Motion and noise: Foam layers can help absorb movement, while the air system and pump components may introduce some mechanical sounds, especially during adjustment.

Common Questions About Materials and Daily Use

Does the foam in these mattresses break down over time?

Like most foam mattresses, foams can soften gradually with use. Higher-density and better-constructed foams tend to feel supportive for longer, while very soft foams may show impressions more quickly. The air chambers themselves are usually built for long-term use, but the foam comfort layers are what most sleepers notice changing first.

Are these mattresses all-foam?

No. While they include foam, the primary support system is air, not springs or a solid foam core. You’re essentially lying on a foam-and-fabric comfort system over an adjustable air base.

What Is a Sleep Number Mattress Made Of if I have material sensitivities?

If you have concerns about specific materials (for example, certain foams, fabrics, or plastics), it’s helpful to:

Check for detailed material lists for each model
Look for any information about off-gassing, fabric types, or chemical treatments
Consider how sensitive you are to smells from new foams or plastics, which can be noticeable at first on many new mattresses

✔️ Quick Mattress Takeaways

Key points consumers should understand about “What Is a Sleep Number Mattress Made Of”

The core is built around adjustable air chambers, usually made from durable synthetic materials designed to hold air securely.
The comfort you feel comes mostly from foam layers on top, such as polyurethane foams and contouring foams, which shape how soft, firm, or pressure-relieving the bed feels.
A fabric cover (often polyester-based) and foam edge rails hold everything in place and influence edge stability and surface feel.
The materials affect firmness range, pressure relief, motion feel, temperature, and durability, so it helps to know what is inside before choosing a model.
These beds are not all-foam or all-spring; they are a hybrid of air support plus foam comfort, which creates a distinct feel compared to traditional mattresses.

Understanding what a Sleep Number mattress is made of gives you a clearer picture of how it might feel, how it may change over time, and whether this combination of air support and foam comfort aligns with your sleep needs and preferences.