Crack filling is a bit of a double-edged sword. Cracks that are left unfilled allow water intrusion that can compromise the base structure of pavements. Most soils in the Bay Area have low R-values meaning they lose stability and strength when wet, so keeping water intrusion to a minimum is important, especially if the pavement ever needs to support heavy loads.  Cold applied crack fillers tend not to protect and last as long as hot applied rubber, but they are also less noticeable, less expensive, and can be done the same day as sealcoating. Hot rubberized crack fillers are much more effective for wider cracks and longer lasting, but they also cost more, are more noticeable and unsightly, and are best performed on a separate day in advance of sealcoating. Depending on the volume and type of traffic, width of cracks, quantity of cracks, age of the pavement, and aesthetic considerations, we can make a recommendation that balances cost, effectiveness, and appearance. Because crack filling without sealcoating or slurry sealing afterwards tends to be unsightly, we generally recommend completion after repairs and prior to the surface treatment.