Regular home maintenance is a must in protecting your investment and maintaining a sound structure for decades to come. The common theme in one of my home inspection walk-throughs is neglected maintenance, and one of those maintenance activities includes caulk maintenance. Exciting right? I've compiled some answers to the more common questions I get related to caulking. I've also included some details I thought may be useful for your next caulking project.

Should I Remove Old Caulk?

Absolutely! A painter's 5-in-1 tool or putty knife can make the job easier. There are also chemical caulk removers on the market, but in a pinch, I've found a heat gun, or even a hairdryer can go a long way into loosening up the old caulk and making the job easier.

After removing the old caulk, be sure to thoroughly clean and rinse the surface. Remove any debris, loose paint, dirt, grease, oil, soap, etc. Depending on the location, a wire brush can help, but I wouldn't recommend using this on a potentially damageable material, like a bathtub, or flooring.

How do I fill large cracks?

For exterior cracks, there are a few options available to you. In an area that is difficult to adequately fill, like between a stone foundation, and a sidewalk, I'd recommend clearing out as much debris as possible, vacuum out any remaining dirt, debris, etc. Fill with an exterior grade expandable foam, stopping before it reaches the surface. Once this has fully cured you can then cover the foam with an exterior self-leveling caulk.

For relatively uniform and accessible cracks, like those in a driveway, I'd recommend a Filler Rope or backer rod. These will fill gaps around 1/4 inch wide and 1/2 inch deep and provides a good surface for caulk adhesion.

How do I apply Caulk?

Simple, practice. Practice a lot. First, you'll want to cut the nozzle at a 45° angle and to the size of the bead you're aiming for. Place this 45° angle parallel to the surface being caulked, and apply a few feet at a time. Now you'll want to smooth out the caulk, also known as "tooling".

You can use a finger, spoon, foam brush, beading tool, etc. Ideally, you're looking to smooth out the bead while providing good adhesion of the caulk to the surface you're trying to seal. It's both an aesthetic process and a necessary one. But don't worry, if you mess up, you can clean the bead out, clean the surface, and start over.

If you're using a solvent-based caulk, like Lexel, you can use mineral spirits to making tooling easier. If you're using a water-based caulk, use water.

You can use blue tape along the sides to assist for a neater appearance, but remove it right away after smoothing.

Which type of Caulk should I use?

For the vast majority of caulking needs both exterior and interior needs I recommend Lexel by Sashco. If you've had a home inspection by me, there's a good chance I've mentioned this stuff. However, there are circumstances that other products are better suited for the specific application requirements. In that case, I recommend going here to find a full range of products for your needs.

If you prefer a brand other than Sashco, not a problem. I've outlined the specific caulking materials, average lifespans, and best use below in this graphic I've put together.

Midwest Home Inspect, Minnesota Home Inspector caulk recommendations
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