How to Seal Drywall


Once the drywall has been installed on the interior skeleton of your home, the seams between the wallboards must be patched with joint compound. Also known as "mud" among homebuilders and contractors, joint compound provides an air- and water-tight seal between the newly installed drywall, making it an integral part of home insulation and weatherproofing. Mud can also be used to repair holes, both small and large, or to add a textured look to a smooth sheet of drywall.

Things You'll Need

  • Joint knives (various sizes)
  • Joint compound
  • Drywall sandpaper
  • Sanding block
  • Refer to the mixing instructions on the back of your container of joint compound. Most products arrive ready-mixed, but some must be thoroughly mixed with a small amount of water to ensure proper adhesion to the drywall.

  • Apply joint compound up and down the length of the seam. Use a generous amount of compound to ensure that it fully fills the crevice.

  • Drag the blade of your joint knife along the seam to pack in the compound. Scrape the compound smooth by angling the blade against the seam and moving it down the length of the seam.

  • Continue the above steps for each seam requiring sealing. Conserve compound by scraping any unused "mud" back into the container.

  • Let the compound cure for at least 24 hours, or for the time suggested on the container's label.

  • Wrap a sheet of drywall-specific sandpaper around a sanding block and smooth away any imperfections in the dried compound.

Tips & Warnings

  • Fill any holes in your drywall by scooping a generous amount of compound over the affected area. Using the tip of your joint knife, push the compound into the hole until it is sufficiently packed. Perform Steps 3 through 6 as described.
  • Do not inhale or ingest the joint compound.
  • Keep pets and children away from your work area.

Related Searches


  • Photo Credit Jupiterimages/ Images
Promoted By Zergnet


You May Also Like

  • How to Texture Walls With Drywall Mud

    Walls textured with drywall mud can add beauty to your home. Buy special texturing tools or use a broom, dry brush or...

  • How to Apply Drywall Mud

    Drywall mud, or joint compound, is used to smooth joints in walls and ceilings before they're painted or wallpapered. When it's properly...

  • Applying Mud to Drywall

    Mud needs to be used on drywall before it's taped. Learn how to add a new bathroom to a home, including tips...

Related Searches

Check It Out

22 DIY Ways to Update Your Home on a Small Budget

Is DIY in your DNA? Become part of our maker community.
Submit Your Work!