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Now that winter is over, it's time to walk around the outside of the house and see what the weather has wrought.

Typically, the caulk (sometimes called sealant) around the your home's exterior -- which keeps water out of walls and keeps your home airtight -- takes a beating over the course of winter. Plus, the wood parts of your house expand and contract depending on the temperature and moisture in the air. Over time, the caulk stiffens, dries up, cracks and disconnects from the surfaces it's designed to stick to. If you see this, it's time to replace the damaged portions with new caulk.

First, take a walk around your house and check out where the window trim meets the walls and the sills. Look around for where pipes or cables go through walls. Look for spots where the caulk is cracked or separated.

Most likely, you'll see some caulk whose time has come and gone -- and that's perfectly normal. Caulk isn't designed to last a long time. It's important to replace that caulk, though, to keep water from getting into walls and from seeping behind unfinished trim, siding and framing boards. Water droplets are tricky. They can migrate up, down and sideways. When water gets where it shouldn't be, wood can soften and degrade, attracting pests and mold.

Here's what to do to prevent all of that.

• Gather together tubes of caulk (try this zero VOC caulk), a caulk gun, a blade, a putty knife and screwdriver to pry away the old caulk, thin gloves if desired, and cloths for clean up. If you're using an already-opened tube of caulk, here's how to unclog it.

• Chip away and remove old and degraded caulk and clean the area. You can use a screwdriver for this. The more degraded the caulk, the easier it will release. If damaged caulk still sticks in some places, you may need a blade to cut it away.

• Load the tube of caulk into a caulk gun. Cut the tip of the tube at an angle. Position your blade on the tip so that the size of the hole you get is a little smaller than the gaps you want to fill. (Using an old, clogged-up tube of caulk? See how unclog it.)

• Seal the gaps in your home's exterior with caulk, applying a smooth bead.

• Use your finger (covered with a thin, protective glove if desired) to smooth out the caulk and make sure there are no holes or gaps. Have a cloth nearby to clean up messes.

• Paint over the caulk to make it blend in with the house. If you're using white caulk on white surfaces, there's no need to paint. Avoid "clear" caulks as it just looks tacky.

• If a gap is extra wide and deep, you might want to fill it with a foam backer rod to avoid having to fill the entire gap with caulk. Ideally, you push the foam strip into the gap until the space to be filled is equal in width and depth. Then, apply the caulk as above.

Do this once a year, replacing the caulk that has given out, and your house will be protected from a lot of risks.

Read more on caulks and sealants from the National Institute of Building Sciences.

Remove White Caulk from Kitchen
(Charles & Hudson)
How to Winterize Your Doors and Windows (ShelterPop)


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