Vinyl comes in two distinct formats: sheet and plank. Sheet vinyl is a continuous roll, typically 6 or 12 feet wide, that is laid down as nearly seam-free as possible. The seams are minimal in number and carefully sealed with a seam sealer or heat-welded at the joints. Plank vinyl consists of engineered boards similar to laminate, locked together with very little gapping between them. Each plank has a perimeter joint at every edge where it meets adjacent planks.
The difference between these two formats is profound in terms of water vulnerability. A sheet vinyl floor has almost nowhere for water to get in except at perimeters where it meets the baseboards and at penetrations for fixtures. A plank vinyl floor has joints at every single board edge — the cumulative total length of all joints is enormous and presents many potential pathways for water entry. A leak through one compromised seam on a sheet floor affects a localized area. A leak that travels along the joints between multiple planks can affect a very large area as the water migrates along the joint lines.
Water coming from below the vinyl is equally important as water on top. Both sheet and plank formats need a moisture barrier between the vinyl and the subfloor if the subfloor is concrete or shows any moisture. If that moisture barrier is compromised, missing, or improperly installed, water coming up from below degrades both the vinyl material and the adhesive holding it down, eventually causing the floor to delaminate. That failure mode is completely invisible until the floor suddenly becomes soft underfoot or starts buckling visibly, at which point repair means complete removal and replacement of the affected area.
Vinyl underfoot is notably warmer and softer than rigid finishes like tile or stone. It gives and flexes slightly under weight with each step, which is comfortable for standing and reduces fatigue. Without radiant heating beneath it, vinyl remains room temperature and feels warmer to the touch than tile would. With radiant heat installed below it, vinyl conducts heat less efficiently than tile does, so the warmth underfoot is modest. Vinyl tolerates a slightly imperfect floor beneath it better than tile does, but imperfections can still show as visible or tactile ridges or telegraphing of the substrate variation.