Conclusion

There are a number of factors to consider when determining performance of insulation in buildings:

Climate zone. The thermal performance of insulation has been shown to vary at different temperatures. Stone wool improves at lower temperatures while foam polyisocyanurate insulation loses performance at low temperatures due to aging, dimensional instability/gaps, and lower temperature performance. It is important to recognize and use the most relevant R-values for design, energy modeling, construction, and operational performance.

Blowing agents. Polyisocyanurate insulation materials use blowing agents to provide thermal performance which diffuse from the product over time. Stone wool does not contain blowing agents.

Thermal expansion coefficients. Different insulation materials have different expansion & contraction rates due to changes in temperature and these changes result in permanent deformations. Foam plastics have a much larger rate of expansion and contraction than stone wool. Foam insulation boards can leave significant gaps in the thermal layer where stone wool remains stable and virtually unaffected.

Moisture and fire resistance. Stone wool provides strong performance in both of these areas particularly when compared to other types of insulation.

Acoustics. Some insulation materials will perform better than others when installed in buildings for many of the same reasons they perform better for thermal control applications. Stone wool insulation has been shown to provide excellent acoustic control.

When an insulation product can be selected to meet all of these design criteria, then it has the highest likelihood of contributing to a successful design solution with long-term sustained performance.

Peter J. Arsenault, FAIA, NCARB, LEED AP, is a nationally known architect, sustainability consultant, technical writer, and continuing education presenter. www.linkedin.com/in/pjaarch

 

ROXUL Inc. is a subsidiary of ROCKWOOL International, the world’s largest producer of stone wool insulation. ROCKWOOL International is a publicly held company, which trades on the Copenhagen Stock Exchange. Operating 27 factories worldwide, the Rockwool Group employs over 9,800 people and features a global network of sales companies, trade offices, and dedicated commercial partners. ROXUL products are thermally efficient, non-combustible, sound absorbent, water repellent, non-corrosive, and are resistant to mold, fungi, and bacteria growth. For more information on ROXUL commercial products, please visit www.rspec.com.