How To Caulk Siding Yourself and Repair Any Cracks

A quick, effective project to tackle this weekend

Man caulking siding on a ladder
Photo: kali9 / E+ / Getty Images
Man caulking siding on a ladder
Photo: kali9 / E+ / Getty Images
Kate Fann
Written by Kate Fann
Contributing Writer
Updated February 6, 2024

Difficulty

Simple

Saturday skill builder.

Time to complete

1 hour

Cost

$25–$50

Just a short shopping trip (or online order).

Need professional help with your project?
Get quotes from top-rated pros.

What you'll need:

TOOLS
  • Caulking gun
  • Rag
  • Utility knife
SUPPLIES
  • Caulk
  • Filler rope
  • Moistened sponge
  • Ladder
  • Painter's tape (optional)

Caulking is a powerful tool any homeowner has in their arsenal to quickly repair any small siding damage. If you have cracks, gaps, or small holes, caulking can prevent more serious problems from occurring, like water damage. Read on to learn how to caulk siding to quickly fix any small issues with your siding.

Angi Tip
Contact a pro to diagnose any potential damage to your home's siding, as they may be able to identify damage that is difficult to spot.
Ryan Noonan
Content Editor, Angi

Prepping to Caulk Siding

Most of the tools you'll use to caulk siding you may already have handy so the most important items you'll shop for are a caulking gun and caulk. For a caulking gun, you don't need to splurge on anything high-end, as a straightforward caulking gun will work just fine and cost between $5 and $10.

Then, you'll need to choose the type of caulk to use. There are four types of caulk to pick from: butyl, latex, silicone, or polyurethane sealants. Some products include a mixture of these types. For exterior windows, doors, trim, and siding, silicone caulk or a silicone-latex combination is an ideal option. Butyl rubber is optimal for outdoor applications, such as around gutters.

In some instances, you have the option of choosing a caulk color that matches your siding for a more seamless finish. However, this is not required, and your home will still look great if you use a generic colored caulk. 

Depending on where you're caulking, you may require the use of a ladder or scaffolding. If this is the case, ensure you work with a partner to reduce risk. If you're not comfortable working from a ladder or don't have assistance, consider hiring a siding contractor.

Don’t Forget to Check the Weather

Before you begin your project, you want to check the weather. It takes about 24 hours for the caulk to dry and cure, so avoid starting your project if rain is in the forecast. It's also not advisable to caulk if it's too cold outside, so wait for a day when it's warm (anything above 40 degrees Fahrenheit).

When Not to Use Caulk on Siding

Caulking is a viable solution if you have cracks or gaps or are needing to caulk butt joints, corners, or crevices. However, caulk is not recommended for all types of siding or in every problem area. 

Wood is a house siding option that shouldn’t have siding caulk applied, as this would impede the natural expansion and contraction of the material. Fiber cement siding should not be caulked either unless it does not have flashing. It is also not recommended to use caulk on lap siding styles as each siding board is designed for water to escape through its base. Caulking prevents this natural occurrence, which could result in water damage.

As for areas it's not advisable to use caulk, trim boards resting on the siding should be left without as it would inhibit airflow and possibly trap moisture beneath. The bottom of horizontal siding sheets and the edges of tongue-and-groove panels should be avoided for caulk as they are designed to channel water and permit airflow; the caulk would prevent this from happening.

  1. Clean the Area

    To ensure a lasting hold, begin your caulking project by cleaning the areas to be sealed. Use a utility knife to eliminate any old caulk, flaked paint, damaged wood, dirt, and other debris. If you’re cleaning vinyl siding, a water and vinegar mixture works best, but for most siding, you can wash out the areas with a damp cloth. Let the siding dry out entirely before you caulk.

  2. Inspect for Cracks and Gaps

    Carefully inspect the area you'll be caulking for any cracks deeper than 1/2 inch and wider than 1/4 inch. Fill any detected gaps with a filler rope to enhance the area prior to applying the caulk. Utilizing filler rope not only decreases the amount of caulk needed but also forms the perfect joint design. This enables the caulk to expand effectively, thus reducing the likelihood of it ripping or tearing and requiring further maintenance.

  3. Prepare Tools for Caulking

    Next, you'll load the caulking gun with your caulk tube. To do this, squeeze the release trigger of the caulk gun to draw the rod backward. Keep a grip on the rod while simultaneously pushing the trigger down with your thumb. Using your other hand, draw the rod as far as possible and hold it there.

    Next, use a pair of scissors to cut the nozzle on the tube of caulk at a 45-degree angle. Take the piercing rod on the gun and insert it through the nozzle until it breaks through the tube. With the steel rod still firmly held in place, slide the flat end of the caulk tube into the back of the frame. Position the nozzle so it fits comfortably within the opening at the front of the gun. Gently squeeze the large trigger of the gun to make sure the tube is balanced.

    Once the caulk gun is prepared, dampen a foam brush with water. Set it to the side. You can also choose to apply painter's tape around the area to avoid cleaning any excess caulk.

  4. Apply Caulk

    Now, you're ready to apply the caulk. While you may be tempted to apply one long, continuous line, avoid this as it may result in a partially-depressed trigger. Instead, apply shorter beads of caulk that merge together as you go along the area.

    After applying, take the damp foam brush and carefully blend the caulk to make sure all seams are evenly filled. This will produce a much more polished, professional-looking end result. Remove excess caulk by taking a damp rag and wiping it away. If you've used painter's tape, remove it now before the caulk has time to dry. 

    When you've completed the project, allow the caulk to dry completely. This typically takes 24 hours. You can assess it after it's dried to see if any further work is required.

DIY vs. Hire a Pro

If you love tackling a new project or have experience with caulking, this siding task can be well-executed on your own. Plus, you'll save money to use on other projects since you can complete this DIY for less than $50. The only challenge you might face is using a ladder or simply lacking time in your schedule to complete it. In either case, you may want to hire a local siding contractor or handyperson with exterior repair experience. The average siding repair cost ranges between $40 and $90 per hour for labor.

Did You Discover Damage to the Siding?

Siding isn’t indestructible. Holes, chips, dents, and cracks can look small. Behind the scenes, they can quickly snowball into big problems. During your DIY project, you might discover damage that your weekend caulking can’t fix. These openings leave space for moisture to collect and can cause further—and sometimes extensive—damage to your home. 

If you spot any damages or are dealing with siding (e.g. wood or fiber cement) that doesn’t work well with caulk, get a siding contractor to your house ASAP. Installing or repairing siding is best in moderate temperatures, so depending on the extent of your damage and the season, your contractor might push your repairs to the nearest fall or spring seasons.

Frequently Asked Questions

Caulking should be re-applied roughly every five years. It's natural for a home to settle and separate caulking from joints, so it's a good idea to assess the home every two years. A consistent siding maintenance schedule will help you see if the caulking is needed and address any potential issues before they occur.

Need professional help with your project?
Get quotes from top-rated pros.
Learn more about our contributor
Kate Fann
Written by Kate Fann
Contributing Writer
Kate Fann is a content writer with ten years of online writing experience, taking a specialized focus on strategic SEO.
Kate Fann is a content writer with ten years of online writing experience, taking a specialized focus on strategic SEO.
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