Does Spring Mattress Have Fiberglass? What to Know About Springs, Fire Barriers, and Materials

If you’re asking “Does spring mattress have fiberglass?”, you’re likely concerned about what’s inside your bed and whether it’s safe and comfortable. This FAQ-style guide explains how spring mattresses are built, why fiberglass is sometimes used in mattresses, and how you can check what’s in yours.

Do Spring Mattresses Contain Fiberglass?

There is no single answer for all brands and models. Some spring mattresses may contain fiberglass, while others do not.

Fiberglass is sometimes used in mattresses as part of the fire barrier layer. This layer helps the mattress meet flammability regulations. It’s usually placed under the outer fabric cover and above the comfort layers, not in the springs themselves.

Whether a specific spring mattress has fiberglass depends on:

The materials chosen by the manufacturer
How the fire barrier is constructed
The price point and design of the mattress

Because of this, you cannot assume all spring mattresses have fiberglass, and you also cannot assume they are all fiberglass‑free.

Why Would a Spring Mattress Use Fiberglass?

What is fiberglass doing in a mattress?

Fiberglass is a material made from very thin strands of glass. In mattresses, it’s often used as an inexpensive, non-foam fire barrier. Instead of treating foams or fabrics with chemicals, some manufacturers place a fiberglass-based layer under the cover to help the mattress resist open flame.

Why it matters to consumers

Fiberglass inside a mattress is normally meant to stay fully enclosed. Problems can arise if:

The outer cover is removable and is taken off
The cover becomes torn, worn, or heavily damaged
The mattress is cut, opened, or altered

When that happens, tiny fiberglass particles may escape into the surrounding area. Many people want to avoid the possibility of loose fiberglass in their bedroom, which is often why they search for “Does spring mattress have fiberglass?” before purchasing.

Where Is Fiberglass Located in a Spring Mattress?

If a spring mattress uses fiberglass, it is usually:

In the fire barrier layer, under the main fabric cover
Sometimes woven into a knit or fabric-like layer
Not inside the steel coils or springs themselves

The springs are typically made of metal. Any fiberglass component would be part of the cushioning or protective layers, not the core support system.

How Can I Tell If My Spring Mattress Has Fiberglass?

1. Read the law tag and material label

Every mattress sold new should have a law tag or materials label sewn onto the side or end. This tag lists the main contents by percentage.

Look for terms such as:

“Fiberglass”
“Glass fiber”
“Glass wool”

If these appear, the mattress includes fiberglass. If the tag lists other fire barrier materials (for example, “rayon,” “polyester,” or “inherent fire barrier fiber”) and does not mention glass fibers, it may be fiberglass‑free. However, wording can vary, and not all tags are equally detailed.

2. Check product descriptions and packaging

Descriptions sometimes mention “fiberglass-free fire barrier” or highlight specific natural or synthetic barrier materials. If the website, brochure, or packaging clearly states there is no fiberglass, that is usually a direct answer. If the information is vague about the barrier layer, it may be worth investigating further.

3. Look for a removable cover warning

Some mattresses with fiberglass inside include warnings not to remove the cover. If the tag or instructions say something like “Do not remove cover” in connection with “fire barrier,” this can be a sign that fiberglass is used beneath the cover.

Are All Spring Mattresses Without Fiberglass?

Not necessarily. Some spring mattresses:

Use alternative fire barriers such as specialty fabrics, treated fibers, or other non-glass materials
Are described as “fiberglass‑free” as a design choice
May be built with non-removable covers and different barrier constructions

At the same time, many other mattresses—whether spring, hybrid, or foam-based—can use fiberglass for the same regulatory reasons. The presence or absence of springs alone does not determine whether fiberglass is used.

What Should You Consider If You’re Concerned About Fiberglass?

If your main question is “Does spring mattress have fiberglass?” because you want to avoid it, consider the following:

Check labeling before buying: Look closely at the materials list and any mentions of glass fibers or fiberglass.
Avoid removing the cover: If your existing mattress has a sewn-on cover, keep it intact to help contain any internal fire barrier.
Handle damaged mattresses carefully: A heavily ripped, burned, or cut spring mattress may expose internal layers, including any fiberglass barriers.

These steps help you understand and manage what’s inside your mattress, regardless of the specific brand or construction.

✅ Quick Mattress Takeaways

Key points consumers should understand about “Does Spring Mattress Have Fiberglass”

Not all spring mattresses contain fiberglass, but some do as part of the fire barrier.
Fiberglass, if present, is usually in the fire barrier layer under the cover, not in the metal springs.
The law tag and materials label are your best tools for checking whether fiberglass or “glass fiber” is listed.
Warnings about removing the cover can indicate a fiberglass barrier beneath.
Many mattresses of all types—spring, hybrid, or foam—may or may not use fiberglass; the mattress type alone doesn’t guarantee anything.
If you are concerned about fiberglass, focus on clear material disclosure and intact covers, and look for mattresses that explicitly describe their fire barrier materials.

Understanding how spring mattresses are constructed and how fire barriers work can make the question “Does spring mattress have fiberglass?” much easier to answer for any specific model you’re considering.