§ 19020
54 words·~1 min read·
/ca/business-and-professions-code/19020·A research copy — for the controlling text, always check the official state or federal source. Not legal advice.
“R-value” means a measure of thermal resistance of material or composite materials. “R-value” is equal to the reciprocal of the conductance of a given material, or
R-value =
1
conductance of the material
where the conductance of the material is: Btu (hour × square foot × Fahrenheit degree average temperature difference between two surfaces).