Basement ceilings tend to be a hot mess. Regardless of how they’re framed, they are riddled with a gaggle of wires, pipes, ducts and fixtures. The notion of routinely sealing-up access to vital home systems with a drywall ceiling may not be a very practical idea to most homebuilders and their buyers.

Yet that scenario now faces many builders as they comply with stringent new floor assembly fire-rating requirements (2012 IRC Section R 501.3) being adopted and enforced by more and more building code jurisdictions.

To meet the new code, home builders who build with I-joists can opt to finish the basement ceiling assembly with fire-rated drywall or install a sprinkler system. Both approaches are less than ideal for many home builders.

Alternative fire-rating solutions are gaining fast traction not only because they meet code for a fire-rated I-joist assembly, but these solutions also presents builders with a “bonus assortment” of high-value benefits at no extra cost.

Increasingly, more and more homebuilders turn to Stone Wool Insulation Batts as the solution of choice.

The Stone Wool Batt Solution

There are many reasons why stone wool insulation batts are fast-emerging as a code compliance favorite. For starters, working with stone wool insulation batts barely disrupts the building process. “There’s no need for extensive retraining, or changes to new subcontractors, new suppliers, and new business relationships,” says Greg La Vardera a Philadelphia, Pa.-based residential architect

What’s more, stone wool insulation batts meet code with proven fire suppression characteristics (tested per ICC Acceptance Criteria AC-14 section 4.4, following ASTM E119). Stone wool is a rock-based mineral fiber comprised of a volcanic rock and a by-product of the steel and copper industry. The minerals from these sources are melted and spun into fibers, creating a product that is essentially impervious to fire (melting point: up to 2,150° F.). Other benefits include:

  • Quieter Home. High density stone wool batts provide better sound absorption at low frequencies, providing superior sonic separation between floors. The unique non-directional structure of stone wool insulation is denser than traditional insulations. The higher density effectively reduces airflow. Reduced airflow means less sound transmission.
  • Greener Home. Stone wool batts are GREENGUARD Gold-certified for indoor air quality and CFC- and HCFC-product and process. Stone wool is made from natural and recycled materials.
  • Healthier Home. Stone wool batts resist water, rot, mold, mildew, and do not support fungi and bacterial growth. Stone wool insulation is an inorganic product and passes ASTM C1338, a standard fungi resistance test, with zero fungal growth.
  • Contractor–Friendly Home. Friction-fit batts conform to normal I-joist spacing. Batts are easy to cut with a serrated blade and require no special training to install.

As you consider ways to meet basement ceiling fireproofing code, keep stone wool batts in mind. Nothing else compares to them for their unbeatable combination of fireproofing, acoustics, energy conservation, and installation speed and simplicity.

For more information including technical data sheets and case studies, visit or call 800.265.6878.