Foam Fundamentals: Comparing Cushion Foam Densities for Comfort, Durability, and Outdoor Use
When reupholstering furniture, cushion comfort is everything. And that comfort starts with what’s inside — the foam. At Leon Custom Upholstery, we help clients understand how foam density affects comfort, longevity, and performance. In this post, we’ll explore the different types of foam densities using both PCF (pounds per cubic foot) and HR foam grading systems such as HR35, HR40, and HR50, plus we'll discuss the best applications — including for outdoor use with Dry Fast Foam.
Understanding Foam Density
Foam density is typically measured in PCF (pounds per cubic foot) — the weight of one cubic foot of foam. The higher the number, the denser and more durable the foam.
In upholstery, we often use High Resiliency (HR) foam, which adds another level of classification. These foams are labeled as HR followed by a number — for example, HR35 or HR40 — which refers to two properties:
HR = High Resiliency (foam that rebounds quickly and retains shape)
Number (e.g., 35) = The foam’s density in kg/m³
Comparing Foam Densities
✅ Low-Density Foam (HR25–HR30 | 1.3–1.8 PCF)
Best For: Occasional-use back cushions, decorative pillows
HR Ratings: HR25, HR28, HR30
Comfort: Soft and light
Durability: Less durable over time, more prone to sagging
Use Case: Good for lightweight applications where softness is key
✅ Medium-Density Foam (HR35–HR40 | 1.8–2.5 PCF)
Best For: Everyday residential seat cushions, sofas, lounge chairs
HR Ratings: HR35, HR36, HR38, HR40
Comfort: Balanced feel — not too soft or too firm
Durability: Withstands daily use, moderate firmness
Use Case: Most commonly used foam in home furniture upholstery
✅ High-Density Foam (HR45–HR50+ | 2.5–3.2+ PCF)
Best For: High-traffic seating, commercial furniture, mattresses
HR Ratings: HR45, HR50
Comfort: Firm and supportive
Durability: Long-lasting, resists sagging and breakdown
Use Case: Ideal for restaurants, waiting areas, and firm residential support
What About Outdoor Cushions? Meet Dry Fast Foam
For outdoor furniture, Dry Fast Foam is the industry standard. It features large open cells that allow water to pass through quickly, making it mildew-resistant and ideal for wet or humid climates.
✅ Dry Fast Foam
Best For: Patio furniture, poolside seating, boat cushions
Density: Typically around 1.8–2.2 PCF but structured for breathability, not weight
Comfort: Medium-firm
Performance: Fast-draining, mold-resistant, UV-tolerant
Use Case: Ideal for all-weather outdoor use
Which Foam Is Right for You?
The right foam depends on the use, location, and feel you’re looking for. At Leon Custom Upholstery, we offer expert guidance and free consultations to help you select the perfect foam — whether you need long-lasting commercial support, plush back cushions, or water-resistant outdoor foam.