25 ILCS 82/5

(a) Every bill, except those making a direct appropriation, the purpose or effect of which is to directly increase or decrease the cost of constructing, purchasing, owning or selling a single family residence shall have prepared for it, before second reading in the house of introduction, a brief explanatory statement or note that shall include a reliable estimate of the anticipated impact. (b) Every proposed rule of an agency, the purpose or effect of which is to directly increase or decrease the cost of constructing, purchasing, owning, or selling a single family residence shall have prepared for it, before approval by the Joint Committee on Administrative Rules pursuant to the Illinois Administrative Procedure Act, a brief explanatory statement or note that shall include a reliable estimate of the anticipated impact. As used in this Act, "rule" and "agency" have the same meanings as in the Illinois Administrative Procedure Act. (c) These statements or notes shall be known as housing affordability impact notes.