Exterior Caulking
 

Before Your Begin


Introduction
The purpose of exterior caulking is to apply a bead of flexible sealant to fill or cover cracks, seams and gaps where drafts or moisture might get into your house or conversely, where heated or air-conditioned air might leak out. Caulking helps keep your house weather-tight, lowers heating and cooling bills, and prevents damage to structural members. It can also help keep insects and other “critters” out of your house. When you caulk before painting, it eliminates edges where the paint may start to peel, so you won’t have to repaint as often.

This tutorial provides helpful hints and tips to do the job quickly and without hassles. By following these easy steps, you’ll enjoy greater comfort, and protect the investment you’ve made in your home.


Skill Level & Time To Complete
It varies depending on the size of the house and the number of people working. For a typical ranch house, consider the following estimates as a starting point:
• Beginner - 4 to 5 hours
• Intermediate - 3 to 4 hours
• Advanced - 2 to 3 hours

Cautions
Many of the steps that follow may require a ladder. Use care, and be aware of where you are at all times. Follow all precautions on the ladder’s warning stickers.

Common Mistakes
Don’t go back over a freshly-caulked area until the caulk has had a chance to cure.

Many of the steps that follow may require a ladder. Use care, and be aware of where you are at all times. Follow all precautions on the ladder’s warning stickers.

Helpful Tips
Remove all old caulk and make sure the surface where you apply the new caulk is clean and dry.
 

Step by Step Instructions
1. There are two factors to consider in choosing caulk. The first is chemistry. Generally, any brand of exterior silicone caulk will give excellent results. Don’t use interior-grade products for outside applications. The second factor is the warranty. The longer the warranty period of the caulk the better quality it is. Caulk with a 40-50 year warranty is better than that with a 25-30 year warranty; and 25-30 years is better than 15-20. Higher quality caulk will seal better and stay more flexible, and is worth the extra cost.
2. To load the caulk gun, use your thumb to press the release on the rear of the gun, and pull the plunger all the way back. Slip the cartridge into the gun and push the plunger in snugly. Take your thumb off the release.
3. Cut the end of the nozzle on the cartridge so the opening matches the size of the gap or seam you’re sealing. Then use a screwdriver or length of stiff wire to puncture any inner seal in the cartridge.
4. Place the nozzle at a 45° angle to the seam being sealed. Gently squeeze the handle of the caulk gun and draw the gun backwards, toward yourself. It takes just a little practice to match the pressure on the handle and the speed at which you move the gun to get a smooth, even flow. When you can’t squeeze the handle any more, release it and it will spring back out, ready for you to continue. Caulk may flow more quickly at the end of each squeeze, so take care you don’t get a “blob” all at once. Caulk will also continue to flow a little more evenly when you release pressure on the handle; wipe up any extra with a rag or paper towel.
5. There’s no need to flatten or shape the bead of caulk to get it to look concave, or depressed. When the caulk is first applied, the bead is convex; as it cures, it will shrink slightly and form a concave seal.
6. To seal an especially large or deep gap or seam, you will need more than just caulk. You shouldn’t “fill” a large gap with caulk. Instead, place some other filler material in the opening, such as wood, fabric, paper, insulation or even rope, until the opening can be sealed at the surface.
7. Areas to be caulked include 1) where siding meets doors and windows, 2) along house trim, 3) at corners of the house, 4) around outside faucets and dryer vents, and 5) where the siding meets the foundation.
8. For new construction, or if you’ve installed replacement windows or doors, you’ll want to caulk between the window- or door-frame and the wall studs, before you put the siding (back) on.

Now enjoy your newly weatherproofed home!