AC Myths Busted: Cool Home, Lower Energy Bills

Why You Need This Checklist

Have you ever stood in front of your thermostat wondering if the thing you're about to do is actually saving money — or just something your dad always said to do? Closing vents, cranking up the AC when you get home, buying the biggest unit you can find — these feel like smart moves, but building science expert Dr. Allison Bailes says most of them are costing you more than you think.

Here's the problem: your energy bill doesn't care about your good intentions. A leaky duct system means closing vents pumps air straight into your attic. Turning the AC off all day forces it to battle a fully heated house every evening. And that oversized unit you thought would blast the room cool faster? It cycles off before it dehumidifies anything, leaving you sticky and sweaty in an expensive house. Meanwhile, you're staring at a crawl space full of mold, a garage that could be living space but isn't, and grout that's turning to jelly. Sound familiar?

Imagine instead walking into a home that holds its temperature effortlessly. Your filters are clean, your ducts are sealed, your attic air leaks are plugged, and your thermostat is set to a number that actually makes sense. Your crawl space is dry, your garage conversion is permitted and properly insulated, and you're not throwing money at problems that were never the real issue in the first place.

This Old House has been the most trusted name in home improvement for decades. In this episode, building scientist Dr. Allison Bailes of Energy Vanguard breaks down exactly what works and what doesn't when it comes to cooling your home efficiently. General contractors Zack Deetmore and Charlie Silva walk through real listener problems — from failing grout to humid crawl spaces to garage conversions done right. These are professionals who have seen every mistake homeowners make, and they're telling you directly what to do instead.

This checklist turns everything covered in that episode into a clear, step-by-step action plan. Every myth gets corrected. Every fix gets spelled out. Every professional tip — from air sealing before insulating to hiring the right waterproofing contractor — is right here in a format you can actually use. Print it out, work through it room by room, and stop guessing. Your home deserves better than conventional wisdom.

What's Inside — Preview

Every checklist item comes with actionable notes to guide you — things like "Don't forget to do this before you start," "Avoid this common mistake," or "Set a reminder for 30 days out." Nothing vague, just clear next steps.

AVOID Stop turning off your AC completely when you leave home — set it to a moderate setback instead

AVOID Do not buy an oversized AC unit thinking it will cool your home faster and save energy

AVOID Stop closing vents in unused rooms to save energy

CHECK Check all vents in your home for airflow with the system running

CHECK Inspect ducts in crawl spaces, attics, and basements for disconnected sections

+ 39 more action items inside...

AC Myths Busted: Cool Home, Lower Energy Bills

Why You Need This Checklist

What's Inside — Preview

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