Bus. & Prof. Code, § 19022

(a) An “insulation manufacturer” is any person who produces insulation materials or a combination of materials which, when properly applied or installed without any alteration, dilution, or modification so as to affect the thermal or physical properties, performance, or intended use as supplied by the manufacturer, retards the transfer of heat or cold. “Insulation manufacturer” also includes any person who produces finished products whose function is insulation, including, but not limited to, insulated roof and wall panels, insulation kits, pipe insulation, flexible insulated ducting, spray applied insulation systems, or other similar material.

(b) Anyone who alters, substitutes, or recompounds any insulation product or material shall be considered to be the manufacturer of that particular insulation product.

(c) Any applicator, contractor, or fabricator of insulation materials, who installs, applies, or uses insulation materials for their intended use, without changing the thermal or physical properties of the insulation material, shall not be considered an insulation manufacturer, provided that the manufacturer of the insulation material has been licensed in accordance with this chapter.

(d) As used in subdivision (b), “alteration,” “substitution,” or “recompounding” includes:

(1) The attachment of facings or vapor barriers, including, but not limited to, plastic, metal, felt, paper, or other similar materials.

(2) The compression, expansion, or reshaping of insulation materials.

(3) The addition of, or mixing with, adhesives.

(4) In the case of spray applied or foamed in place insulation, any addition to, substitution of, or deletion from, the chemical system provided by the insulation manufacturers.

(e) This chapter does not apply to the attaching of fiberglass insulation to metal duct work by a licensed contractor using industry-accepted adhesives and metal pins.