Compaction is the step most people never see and the one that decides how long asphalt lasts. Hot asphalt is rolled to squeeze out air and lock the stone together. Under-compacted asphalt stays porous, lets water in and breaks down years early.
Rolling while it is hot
Asphalt can only be compacted properly while it is still hot, so the rollers work right behind the paver. The surface is rolled in overlapping passes, including along the edges and next to walls, curbs and foundations.
Base compaction, too
The granular base underneath is compacted in layers before any asphalt goes down. A firm, even base is what stops the surface from sinking and cracking later.
