Lawn renovation is typically done by slice seeding to improve the existing lawn or start from scratch for a new lawn. If your lawn is mostly weeds with little turfgrass one of your options is to kill the existing lawn and slice seed in a new lawn with one of todays new and improved  grass seed varieties that are more resistant to pest, many of the new varieties have endophytes that protects turf  from insect and drought stress.  Another option is to slice seed the new and improved seed variety into your existing turf to improve the thickness and pest resistance.  Slice seeding is done with a machine to make sure that the seed makes contact with the soil, then Penn Mulch is applied to help keep the seed moist and supplied with food for quick germination and root development.