"Construction" means building, altering, repairing, improving, or demolishing any structure or building or making improvements of any kind to real property.
"Primary contractor" means a contractor that has a direct contractual relationship with a property owner. "Primary contractor" may have the same meaning as a "general contractor", "prime contractor", or "construction manager". A property owner who acts as a primary contractor related to the erection, construction, alteration, or repair of his or her primary residence shall be exempt from liability under this Section.
"Private work" means any erection, construction, alteration, or repair of a building, structure, or other work.
"Subcontractor" means a contractor that has a contractual relationship with the primary contractor or with another subcontractor at any tier, who furnishes any goods or services in connection with the contract between the primary contractor and the property owner, but does not include contractors who solely provide goods and transport of such goods related to the contract.
820 ILCS 115/13.5