How to Seal Asphalt Roof Shingles

Sealing asphalt roof shingles can prolong their serviceable life span, preserving the tile grit and structure (and, with some brands, can even restore a waterproof finish). Many types of coatings prevent against the degrading effects of ultra-violet light, wind, rain and extreme heat and cold. Application is fairly straightforward, but since climbing up and working on a roof in a standing position can be dangerous even for roofing professionals, calling in a tradesman with experience in this product is likely an investment worth making.

Establish Access Plan

  1. Identify best the access point for getting on and off the roof. Steady your ladder on a hard, flat surface there.
  2. Inspect the roof. Look for any missing or damaged asphalt shingles. Replace any missing ones. Nail down any that are in good condition but loose. This step will add to the overall serviceable life of the roof.
  3. Spray (or paint on with an extension roller) a full coat of sealant over the entire roof, including valleys, joints, edges and roof-line peaks.
  4. Allow the first coat to dry for at least an hour. The product may not be completely dry after an hour, depending on the ambient temperature and the weather, but it will be tacky.
  5. Spray or roll on a second coat of sealant. Safely dismount the roof.

Things You Will Need

  • Liquid sealant product
  • Full-nap paint roller with long handle (or pressure spray applicator)
  • Ladder
  • Asphalt shingles
  • Roofing nails
  • Hammer


  • Choose a day for application that is free from rain or threat of rain, so that the job will not need to be repeated.


  • Do not under any circumstances work alone, if you are attempting to coat your asphalt roof shingles as a DIY project. Work with a partner or two, with one of you on the ground at all times to steady the ladder when climbing up and down and to call for help if it should be needed.