How often should you touch up your exterior caulk?

Why bother

Gaps let water and drafts straight in. Standard upkeep. Dull and cheap, and a lot less dull than whatever it's quietly preventing.

What the job involves

1. Pick a dry spell, above about 45 F, no rain coming. Spring or fall is the easy window. Walk the outside and mark the failed joints: window and door trim, where siding meets the corners and the foundation, and around vent and pipe penetrations.
2. Dig the old, cracked caulk right out with a utility knife or putty knife. A heat gun softens the stubborn hardened beads. New caulk won't bond over old, so clear the lot and wipe the edge clean and dry.
3. Cut a tube of exterior-grade caulk (paintable silicone or polyurethane) at 45 degrees, load the gun, and lay a steady bead into each gap a quarter inch or less wide. Tool it smooth with a damp finger so it seats down into the joint.
4. Wipe stray smears with a damp rag straight away. Let it cure, about 24 hours, before you paint over it.

Do it yourself, or pay someone?

Yourself, for most. The whole kit (caulk, gun, knife) runs under $30 and it's a one-to-two-hour job. Hire out only if the work's up high or all over the house: a pro charges roughly $40 to $100 a window, or about $750 to $2,000 to do the full perimeter of a 2,000 sq ft house, supplies usually included.

What skipping it costs

$500 to $2,400 is what it runs to repair the wood once water has crept in behind a failed joint, with the national average dry-rot job landing around $1,425. Minor cases, a window sill or a surface board, sit near the bottom of that. Bigger structural rot runs into the thousands. And rot comes back within a couple of seasons if the source, that cracked caulk, isn't fixed first, so a botched skip just pays twice. A $30 tube does the same thing before any of that starts.

Signs it's overdue

• The bead is cracked, split, crumbling, or has shrunk and pulled away from the surface, leaving a daylight gap.
• You can feel a draft around a window or door frame, or the heating and cooling bills have crept up. Failed seals leak the air you paid to condition.
• Soft, spongy, or discolored wood near a trim or siding joint, peeling paint, or water staining inside near a window. Moisture's already getting behind the seal.

When to start thinking about it

Give yourself about 7 days' notice. That's when Grumpty starts grumbling, so it doesn't land on you the day it's due. Mark it done and Grumpty sets the next one, every 12 months, so you can go back to forgetting it exists.

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