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EXACOR® Underlayment

EXACOR® underlayment panels are specifically engineered to meet the fire-rating[1], sound-rating[1] and dimensional stability requirements of most multifamily and light commercial jobsites. Made of magnesium oxide and an integrated mesh core, EXACOR underlayment panels are fire resistant. In addition, EXACOR underlayment panels can offer a base for floor coverings that eliminates the need for gypsum underlayment and installs 30% faster[2] than gypsum underlayment.

  • Underlayment Panel, 1/2" × 4' × 8'

  • Underlayment Panel, 1/2" × 4' × 9'

  • Underlayment Panel, 1/2" × 4' × 10'

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01 Products

Underlayment Panel, 1/2" × 4' × 8'

Panel Count 38
Fire Resistance ASTM E119, ANSI/UL 263

Underlayment Panel, 1/2" × 4' × 9'

Panel Count 33
Fire Resistant ASTM E119, ANSI/UL 263

Underlayment Panel, 1/2" × 4' × 10'

Panel Count 32
Fire Resistant ASTM E119, ANSI/UL 263

Performance Category

Panel Size

Edge Profile

Fire-Resistant Assemblies

Code Evaluation Report

Approx. Weight Per Panel

Panels Per Unit

Nominal 1/2" Thickness (12 mm)Nominal 4' × 8' (1219 mm × 2438 mm)Straight (Square) EdgeUL L528, L501, L502, L525, L528, L602, M500ESR-463586.4 lbs.38
Nominal 1/2" Thickness (12 mm)Nominal 4' × 9' (1219 mm × 2743 mm)Straight (Square) EdgeUL L528, L501, L502, L525, L528, L602, M500ESR-463597.2 lbs.33
Nominal 1/2" Thickness (12 mm)Nominal 4' × 10' (1219 mm × 3048 mm)Straight (Square) EdgeUL L528, L501, L502, L525, L528, L602, M500ESR-4635108.0 lbs.

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02 What Is MgO

Magnesium oxide (MgO) offers simple strength and streamlined installation for a building panel with exceptional workability.

MgO panels are cementitious panels that are primarily made of inorganic materials reinforced with layers of glass fiber mesh. EXACOR® MgO panels are manufactured to provide a streamlined solution for strength, fire resistance and sound performance.

Learn More About MgO

  • Speed & Ease of Installation

    A third-party time testing by Home Innovation Research Labs showed EXACOR® panels can be installed 30% faster[2] than traditional wet-laid gypsum in underlayment applications and only require a single trade.

  • Sound Absorption

    Can help achieve sound ratings without the need for a sound mat when used as part of a STC/IIC-tested floor/ceiling assembly.

  • Fire Resistance

    Inherently fire resistant throughout and provides fire resistance as part of fire resistance–rated wall and floor/ceiling assemblies.

  • Durability

    Tough enough to handle jobsite conditions, withstands exposure to moisture and does not warp, expand, cup or delaminate like other wood panels do.

  • Inherent Strength

    Contains a proprietary layered mesh reinforcement for added structural value.

  • Quality Assurance

    Manufactured under a quality control program with inspections by ICC-ES and Underwriters Laboratory (UL) to ensure consistent product performance.

  • Optimize Material & Labor Costs

    High-performing material that may save time and help reduce materials and trades needed to install.

05 Warranty

Enhanced Experience

If you’re building a multifamily or light commercial project, register your project and complete a preconstruction meeting to access the full range of technical support and warranty benefits for your build, including a transferrable warranty. Review full warranty details and access project registration at the link below.

View Warranty

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