Gold Bond® SoundBreak XP Retrofit® Gypsum Board

Improve the acoustical performance of an existing wall assembly.


3-Part Guide Specs




Sound Control Without the Demolition

Improve the acoustical performance of an existing wall assembly
  • Apply over existing gypsum board walls where sound transmission is a concern.
  • Improves sound control without demolition.
  • Mold and moisture resistant, provides extra protection against mold and mildew.

5/16" Gold Bond® SoundBreak XP Retrofit® Gypsum Board consists of a high-density, mold- and moisture-resistant gypsum board with specially designed PURPLE® paper on the front and a sound-damping, viscoelastic polymer adhered to the back paper. This acoustically enhanced, fire-resistant gypsum core is encased in heavy, 100% recycled paper on both sides that offers superior abrasion, mold and moisture resistance.

Use SoundBreak XP Retrofit on one side of a gypsum board wall to improve the acoustical performance by creating a constrained damping layer when installed over the existing surface.

GridMarX® installation guide marks are printed on the face paper surface to help installers instantly identify stud locations and make accurate cuts without having to pencil in or snap chalk lines.

If looking to reduce sound transmission in new construction, try Gold Bond® SoundBreak® XP® Gypsum Board.


  • Use to improve the acoustical performance of an existing wall assembly, and to achieve a higher Sound Transmission Class (STC) rating for existing interior gypsum board walls where sound transmission has become a concern.
  • Install over existing interior gypsum board walls in residential, multifamily and commercial applications for additional sound damping between rooms or dwelling units.



  • When installing over an existing interior wall assembly, it enhances Sound Transmission Class (STC) values per an independent third-party acoustical laboratory using ASTM E90 test procedures.
  • Achieves increased STC values in a thinner wall assembly, increasing usable floor space.
  • Superior sound damping, cost-efficient material that finishes easily and decorates in the same manner as standard gypsum board.


  • Heavy abrasion-resistant paper and dense core provide greater resistance to surface abuse when tested in accordance with ASTM C1629.
  • Fire-resistant material with a gypsum core that will not support combustion or transmit temperatures greatly in excess of 212°F (100°C) until completely calcined, a slow process.
  • The 5/16" thickness provides a superior sound solution without taking up usable floor space


  • Offers quick installation and lower installation costs, with vertical board joints that do not require acoustical sealant.
  • Installs over existing construction, eliminating the need for demolition.
  • Features GridMarX guide marks on the board to allow for faster and more accurate installation.
  • Easily scored and snapped to exact size without sawing.


  • Helps inhibit mold growth with the highest possible score on mold tests (ASTM D3273 and ASTM G21).
  • Features SPORGARD® technology with extra mold-inhibiting properties.


  • Fights the effects of moisture before damage can occur.
  • Dimensionally stable product with negligible expansion and contraction under normal atmospheric conditions.


Video: SoundBreak XP Family of Products



Products that suit any project criteria

Product Details


Acoustical, Drywall Panels, Mold & Moisture Resistant







Related Resources

Product details and technical documentation.


Drop-In Specs

Fire & Sound Selector

UL GREENGUARD Certification

Frequently Asked Questions

Ready to answer your product and installation questions

What is the ideal wall application for SoundBreak XP Retrofit® Board?

A demising wall application – walls with no penetrations such as windows or doors.

Can I use SoundBreak XP Retrofit Board on the ceiling?

No, 5/16" panels are not permitted for ceiling applications.

Can I use nails instead of screws?

No, screws are required to ensure adequate bond to existing surface.

Can I use adhesive without fasteners?

No, it is intended to be installed with both adhesive and fasteners.

Can SoundBreak XP Retrofit Board be installed horizontally?

No, vertical application provides superior acoustical performance.

Do I have to remove wall moldings prior to installing SoundBreak XP Retrofit Board?

Yes, SoundBreak XP Retrofit Board must cover entire wall surface.

Do I have to use a specific adhesive brand?

No, all adhesives complying with ASTM C557 are acceptable.

Can SoundBreak XP Retrofit Board be installed over wood paneling?

No, SoundBreak XP Retrofit Board is intended to be installed over an existing gypsum board wall in order to achieve optimal acoustical performance.

Which side of the SoundBreak XP Retrofit Board faces out?

Refer to the sticker located on the back of the board. The PURPLE® face should be visible to the installer once the installation is complete.

How do I cut SoundBreak XP Retrofit Board?

SoundBreak XP Retrofit® can be cut using a standard utility knife. Power tools should not be used for cutting, because the polymer can damage the blade.

Does SoundBreak XP Retrofit Board finish like standard gypsum board?

Yes, it can be finished and decorated with standard drywall finishing products.

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National Gypsum Company is the exclusive service provider for products manufactured by Gold Bond Building Products, LLC.