R-Values for double bubble insulation products vary based on the thickness of the overall product itself. Most double bubble insulation products have an average R-Value of 1. But you can achieve a much higher R-Value for your application by the addition of enclosed dead air spaces. However, double bubble insulation shines in applications where radiant heat transfer needs to be controlled and therefore, reflectivity is a much better indicator of a double bubble insulation products effectiveness than its R-Value.
