How to apply silicone caulk and make a perfect bead every time

There are a few main sealants on the market. The most commonly known are Latex based (painter’s caulk), Silicons and Polyurethane. The Latex based caulks are the easiest to work with and tool from all the rest of the sealants. Latex based sealants are not suitable for a variety of applications though.

They are not very adhesive, they become brittle over time, and they are also a lot more susceptible to mold and mildew growth than their counterparts. Latex caulks are perfect for quick touch ups around your house’s interior molding for example, for they dry quick, clean up with water, and are fully paintable.

Polyurethane sealants are very good for pretty much any residential applications. They are supremely durable, very flexible, paintable and have a very large temperature operating range. What makes these types of sealants not very desirable is their price, and extreme difficulty in clean application and tooling. Most polyurethane sealants are alcohol soluble, which makes applying a clean bead of caulk a very complex procedure.

In other words – there is no “tooling” polyurethane caulk (in most cases) after the bead has been applied. The only real good way to ensure a clean bead of polyurethane caulk is to apply it perfectly the first time, and very few pros (not to mention an average homeowner) can do that.

Silicon sealants are perfect for wet area applications. Silicone caulks have an excellent adhesion, they are very flexible, water-proof after curing, their temperature operating range is also very wide. Silicons have a few shortcomings though. They are not paintable.

After a silicone has cured another bead of silicone will not stick to it. Removing old silicone is extremely difficult because of it’s ply-ability as well as a superior adhesion properties. The major gripe with the silicone sealants I hear from homeowners is that – application is a mess. It is very true.

Silicone is very hard to tool into place without getting it all over the place. The trick I’m sharing in this video I’ve picked up many years ago from my shower glass installers. Right after application of the silicone sealant, spray over the fresh bead with an Ammonia-free foaming glass cleaner, and then finger the excess silicone away constantly wiping your tool (or finger) on a clean paper towel. After the tooling of the silicone is complete just let the leftover glass cleaner over-spray dry (don’t try to wipe it off) and you have a perfect silicone bead.