Should I do two coats of Kilz primer?

Should I do two coats of Kilz primer? Whether you need two coats of Kilz primer depends on stain severity and surface. For most general priming over clean drywall or previously painted surfaces, one coat of Kilz 2 or Kilz Original is sufficient. For severe stains like heavy water damage, smoke, fire, pet urine, tannin bleed from wood, or strong color changes like dark to light, two coats provide better blocking and more uniform finish. Manufacturer often recommends one coat, but second coat helps ensure stain does not bleed through topcoat, especially with water-based Kilz 2 which may need two coats for tough stains where oil-based would need one. If first coat still shows stain shadow, apply second coat after 1 hour dry time. For new drywall, one coat of PVA or Kilz is enough. For odor blocking, one coat of oil-based may be enough, but two coats increase sealing. So for light work, one coat saves time and money, for heavy stains or drastic color change, two coats are better for complete coverage and to avoid using extra topcoats. Always allow dry time between coats and follow label directions.