The Basics of Caulking: Preparing, Installing, and Finishing

Often times people wonder what the difference is between caulk and sealant. In short, caulk has less movement capabilities and is not as well performing as sealant. There is a time and place for both caulk and sealant, but first the following steps need to be met.

Preparation

In order to properly “caulk” or “seal” an area, the first thing you need to do is prepare the joint or crack that you will be applying your sealant into. First,  ensure that there is no lose debris or dirt where you will be putting the product. If the crack or joint is dirty, use a wire brush or some form a bristle brush/broom to loosen up the dirt and debris and then blow or vacuum out the loose particles. You should double check to ensure the joint is free of moisture and frost

Lastly, you want to make sure the area you're caulking is not too deep. Recommended joint design is no more than ½” depth. In order to achieve no more than ½” depth on your joint, you may need to insert backer rod to act as a “filler”. Backer rod provides many other benefits such as preventing three-sided adhesion and use of excess product. 

Installation

As you start to gun or caulk the product into your joint, make sure you're applying enough back pressure to the material as opposed to pulling or stretching the material which can cause voids in the cured product. Don't forget to take into consideration the weather conditions, it's crucial the product stays dry long enough to skim over – generally 6-12 hours.

Dow 795 Sealant

Wexford Cartridge Gun

Various Nozzles

Finishing

After the caulk is installed in the joint, you want to “tool” the product to ensure sound adhesion of the material into the substrate. There are many ways to “tool” the product, such as using a caulking applicator tool, the tip of a spoon, or most simply your finger (not recommended by manufactures due to potential for contaminants).

​The main purpose for tooling the caulk/sealant is because you will eliminate any voids in the material that may have been caused by either the joint design or poor installation techniques as mention above. ​

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ACS CONTRIBUTOR
Tom L.