Boron in insulation

Adding borates to insulation improves durability, energy efficiency

For decades, borates have been a mainstay in insulation products and supporting manufacturing processes. In fact, borates in insulation constitutes the largest use of borates in the world. Why?

Because borates are extremely effective at strengthening insulation’s core function: Reducing heat transfer (greater R-Value).

Producing high-performing insulation starts with sourcing quality, consistent borates. If any impurities exist in your raw materials or a concentration is faulty, costly defects can occur—and, even worse, product recalls.

Growing demand to lower the insulation industry’s carbon footprint makes it even more important to partner with a responsible borates supplier such as U.S. Borax. Our technical experts can equip you with detailed product information, discuss sustainability plans, provide value-added projects, and address regulatory concerns.

As a result, you can ensure your products fully harness borates’ multi-faceted benefits and your manufacturing achieves greater process efficiency.

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The role of borates in insulation

Borates are used to produce two types of insulation: Fiberglass insulation and cellulose insulation.

Benefits of borate-based insulation

In fiberglass and cellulose insulation products, borates impart these key attributes:

  • Temperature control (heat loss prevention)

  • Soundproofing

  • Fire retardancy (cellulose insulation)

  • Anti-corrosion

  • Mold and pest resistance

Borate-treated cellulose insulation: Reduce flammability risk

Because cellulose insulation is widely used in building walls and comprised of several highly combustible organic materials (wood, cotton, and other plant fibers), you must take careful measures to reduce flammability risk.

The right concentration of borates can significantly reduce combustion, extinguish smolder, and help you exceed safety standards.

Cellulose insulation is also susceptible to pests, mold, and fungi. As a naturally occurring biocide, borates disrupt the digestive processes of troublesome organisms without harming people.

Ensuring a proper borate application provides long lasting protection for your products, saving you time and money by avoiding recalls.

ASTM International (formerly known as American Society for Testing and Materials) logo

If your company is U.S.-based, borate-treated cellulose insulation enables you to meet the ASTM C739 specification, which establishes requirements for:

  • Corrosiveness
  • Critical radiant flux
  • Fungi resistance
  • Moisture vapor sorption
  • Odor emission
  • Smoldering combustion
  • Thermal resistance

Boron fiberglass insulation: Enabling greater control during manufacturing

Fiberglass insulation (glass wool) is widely used in both residential and commercial buildings—either in blanket form (called “batts”) or roll form.

During manufacturing, borates play a crucial role as a powerful fluxing agent. As a flux, borates lower glass batch melting temperature while providing greater control over viscosity and surface tension.

Two positive outcomes are evident:

  1. Less energy is needed in production

  2. End products have better durability from moisture-and-compression resistant fibers

Ensuring the proper borate concentration is imperative. An insufficient amount derails sensitive melting and fiberizing processes. A poor concentration often means the finished product is less apt to absorb infrared radiation (IR)—the primary function of effective insulation.

Learn more about borates’ role in fiberglass manufacturing.

Why choose U.S. Borax for borates in insulation?

Dependable quality consistency for process control

When you purchase refined borates from us, you can expect every batch to be consistent across key factors you care about such as:

  • Chemical and physical properties

  • Particle size distribution

  • Purity

Our tight quality control thresholds enable stability in your processes so you can create insulation with a higher R-Value.

Dedicated technical experts

Some of the largest manufacturers in the world trust us for their borate insulation needs. Why? Our technical team offers support so you can address any borate-treated insulation concerns you may have, including:

We can also supply you with detailed safety data sheets, with specific information on your production materials such as a fiberglass insulation SDS.

Lower your insulation carbon footprint

At U.S. Borax we’re engaged in several projects to improve sustainability and define how a responsible producer acts across environmental, social, and governance factors (ESG).

By partnering with us, you gain access to borates’ Life Cycle Assessments and emissions data. ESG data like this drives your sustainability goals forward and enables stakeholder visibility into your insulation’s carbon footprint.

20 Mule Team Borax Products

Recommended for cellulose insulation

Optibor logo

Effective at extinguishing both flaming and smoldering combustions, Optibor can stand alone in fire-retardant formulations for cellulose insulation.

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Neobor logo

A concentrated sodium borate, Neobor significantly reduces the flammability of cellulosic materials while also reducing shipping and handling costs.

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Polybor logo

A great solution for customers whose processes demand higher solubility for their fire-retardant formulations.

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Recommended for fiberglass insulation

Neobor logo

Greater glass melt control, improved fibers, better durability, and decreased thermal emissivity are all benefits insulation manufacturers realize when using Neobor.

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Featuring a higher boron concentration and bulk density, Dehybor melts rapidly, saving energy and lowering glass melt emissions.

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U.S. Borax is an associate member of:

Cellulose Insulation Manufacturers Association logo

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Are Refined Borates in Your Sustainability Plan?
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U.S. Borax, part of Rio Tinto, is a global leader in the supply and science of borates—naturally-occurring minerals containing boron and other elements. We are 1,000 people serving 650 customers with more than 1,800 delivery locations globally. We supply around 30% of the world’s need for refined borates from our world-class mine in Boron, California, about 100 miles northeast of Los Angeles.  Learn more about Rio Tinto.

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