On Residential Projects:
As to the general contractor’s notice, no timing is specified, though the sooner the better. Presumably it should be given at the outset. As to the subcontractor’s (including suppliers) notice, the sooner the better, as a preliminary notice posted before the balance due is paid to the general contractor or the owner-builder is effective as to all labor, services, equipment and material furnished to the property by the subcontractor
On Commercial Projects:
Notice must be received within 30 days of first furnishing the labor or materials
Notice must be received within 30 days after claimant’s last delivery, or during the progress of the claimant’s work.