Caulk for Ceiling: When and How To Use It

Thank you to DAP for sponsoring this guide on caulk for ceilings! All opinions are entirely my own. This post also contains affiliate links, but nothing that I wouldn’t recommend wholeheartedly. Read my full disclosure here.

Are you wondering what the best way is to finish the area where the wall meets the ceiling? You’re in luck because today I’m sharing when you should use caulk for the ceiling edge and when you should use tape and drywall mud. I’m also teaching you how to apply caulk at the ceiling edge. Let’s jump in!

When should you use drywall tape and mud at ceiling edge?

• Drywall on walls and ceiling: Traditionally you’ll see drywall tape and joint compound used at the ceiling line and that is the correct usage when you have drywall on both the ceiling and the wall.

When should you use caulking at the ceiling edge?

• Accent on ceiling: If you have any sort of accent on your ceiling, like shiplap, wood planks, beadboard, ceiling tiles or more, you need to use caulk at the edge of the ceiling. We have a shiplap ceiling in here, which is why we were using caulk. 
• Textured walls and ceiling (and want smoother line to paint): If you’re having trouble getting a smooth paint line at the ceiling due to texture, you can add paintable caulk to the corners to smooth things out a bit. This hack such a great idea if you need to get a straight line! 
• Crown molding or other trim work: If you have crown molding or any other type of trim work on the ceiling or the top of the walls, you definitely want to use caulk on the edges before you add your wall color and/or ceiling color.

What’s the best type of caulk for ceiling?

If you’re going to be caulking the ceiling and wall joints, you definitely need to make sure you’re using a caulk that can be painted, first and foremost.

Outside of that, you’ll want to use a caulk for interiors that is made for trim (rather than one made for moisture areas in bathrooms and kitchens). Since you’re caulking on a joint that may have some movement as your home expands and contracts, I’d get something that is crack resistant and flexible. 

Looking for the best caulk for ceilings? We recommend DAP’s Alex Flex, which is an acrylic latex caulk that has silicone added. It works great around molding, window and door trim and baseboards too!

You can get it at your local home improvement store, like Home Depot or Lowe’s, or online retailers, like Amazon. This definitely the caulk that we use most often. We have it all over our whole house because basically every home renovation project requires it!

How To Apply Caulk At Ceiling Edge: Step-by-Step

Step 1: Prep the area

Start by making sure the area is clean and free of any dust or old caulking. If there is old caulk, you can cut or scrap it away with a utility knife. 

If additional cleaning is needed you can use soap and water or TSP and water to remove any dirt, dust, grime or grease from the area. Rinse and let it dry fully. 

Read more about how to clean walls before painting for more details! 

Step 2: Open caulk

Start by cutting the tip of the caulking tube at a 45° angle with a utility knife. 

The further down you cut on the neck of the tube, the more caulk will come out, so be sure not to cut down too far. Remember you can always cut more needed – but you can’t undo the cut. 

Some caulk guns come with a tube cutter. This is usually located on the side of the gun. Just insert the tip of the caulking tube and squeeze the trigger to cut.

However, we prefer a utility knife for a cleaner cut and more control. You can also use a razor blade if you want.

Step 3: Load caulking gun

Now it’s time to break the inner seal of the caulk by inserting the thin metal stick that’s located on the side of the caulking gun. This must be done before the caulking can be applied.

The helpful seal prevents the caulk from drying out, so be sure you are ready to apply before puncturing the seal.

To puncture the seal, simply insert the puncture stick through the tip of the caulking.

Gently move the tube around the stick to make sure there’s enough room for the caulk to come out. Wipe the stick clean with a rag.

To load the caulking gun, put the bottom of the caulking tube in first, then the top. Push the trigger of the caulking gun so the barrel of the gun can tightly grip the tube.

Step 4: Apply bead of caulking

Now, you are ready to apply the caulk! All you do is squeeze the trigger of the caulk gun gently, and the caulk comes out of the tip.

Apply a thin bead of caulk along the top of the walls where it meets the ceiling. 

To stop the flow of the caulk, pull back on the ratchet at the back of the gun or press your finger over the opening of the caulking tube to pause the flow for a moment.

*Optional* – If you’re concerned about getting a nice and neat line for your caulking, you can use painter’s tape on both sides of the area that you’ll be caulking. If you do this, just be sure to remove the tape before the sealant skins over – about 2-5 minutes. To remove, lift the edge up at a 45° angle and pull away from you.

Step 5: Smooth (or “tool”) caulk

Smooth the caulk immediately with your finger or a caulk finishing tool. If you experience any skipping or sticking, simply dip your finger or the tool in some water to help prevent this. 

Be sure that you don’t apply too much caulk before you have a chance to smooth it. You want to tool it (another fancy word for “smooth” it) within 2-5 minutes, definitely before the sealant starts to skin over. We work in sections about 4-5 feet at time. 

Step 6. Let dry and paint

Lastly, you need to wait until the caulking is dry before painting. If you’re using Alex Flex, like we were, it is paint-ready in just 30 minutes. 

Keep in mind that once the caulking tube has been opened, it should be used immediately. If you are pausing on a project, you can purchase caulking caps, like this, to prevent the caulk from drying out. 

There you have it! If you have any sort of accent or trim on or around your ceiling, you’ll need to apply caulking before you apply the ceiling paint or wall paint.