During the summer, it’s nice to go indoors to avoid heat and harmful UV rays.

But sometimes, it’s also hot inside your home, even though you have air conditioning. That’s when it’s time to search for the source and make some improvements.

Here are 5 reasons why your home is hot, and what you can do about it.

A/C ductwork
Ductwork leaks can form where lines branch off or separate. The solution is a bit of metallic foil tape and duct mastic.

1. Ductwork is Leaking

Leaks in heating, ventilation and air conditioning ductwork allow air from your furnace or air conditioner to escape. This wastes energy and raises your cooling costs.

You can often find leaks where lines branch off or separate. When your furnace fan is running, you can feel air escaping the duct.

Once you’ve found the leak, turn off the fan and apply metallic foil tape over the hole or gap. Then apply duct mastic over the tape and joints to improve the seal.

Watch “How to Repair Leaks in HVAC Ductwork” to learn more.

    Your air filter needs to be replaced every 90 days, minimum.

    2. Your Air Filter Needs Replacement

    How many times have you heard how important it is to change your heating and cooling system’s air filter? And how often have you wondered why a $10 or $15 filter is crucial to your system’s operation?

    Here’s the fact: All your home’s air passes through the A/C return’s grill and the filter before it gets to the air handler. When an air filter gets dirty, that dirt passes through the air handler and the buildup makes it work much harder.

    This buildup doesn’t just cause an increase in your cooling bill; it also could lead to a broken air handler unit and expensive repairs.

    Watch “How to Change the Air Filter in Your Home” to learn more.

    Applying window film
    Applying plastic window film reduces solar heat gain and prevents harmful UV rays from entering your home.

    3. Your Windows are Leaking

    If you feel radiant heat in your home when blinds are closed and curtains are drawn, your windows could be leaking.

    This happens one of two ways:

    Your single-pane windows’ glazing is failing. Single-pane windows need glazing putty to prevent leaks. Over time, glazing putty can crack and even fall off.
    If this happens, use a putty knife or paint scraper to remove old glazing around the window opening. Then apply window glazing (available in a can or caulking tube) around the window frame.
    Next, hold a putty knife at an angle to the frame, and use it to smooth the glazing compound.
    Finally, paint over the glazing with exterior house paint after the glazing has set.

    The window transmits solar heat gain. When solar radiation penetrates window glass, a room’s thermal energy increases.
    To reduce harmful UV rays and solar heat gain, add window film that can reflect up to 72 percent of the sun’s heat and blocks up to 99 percent of UV rays.

    Read also: How to save energy with window film

    Attic vent fan
    Installing an attic vent fan is the best way to remove heat from your attic. Better yet, get a solar-powered unit to save money.

    4. Heat’s Coming from Your Attic

    During the summer, heat seeps through your roof, into the attic and causes your air conditioner to work overtime.

    There are two things you can do to prevent heat in the attic from entering your living space:

    Install an attic vent fan. Add an attic exhaust fan near the peak of your roof to keep the attic cooler, lower cooling bills, and make your roof last longer.

    Watch “Keeping Your House Cool During Hot Summer Weather” to learn more.

    Add more insulation. Insulation is important to reduce heat gain and save energy. How well a particular type of insulation works is determined by its R-value, which measures the insulation’s resistance to the transfer of heat.

    Watch “How Much Insulation Do You Need in Your Home?” to learn more.

    Wall insulation
    Insulating your walls can help prevent heat from entering your home. (DepositPhotos)

    5. Heat’s Coming through Your Walls

    If you have a brick home, you know how fast solar heat cooks those bricks — and how soon you start to feel the effects inside.
    That’s why wall insulation is so important.

    Again, before you purchase insulation, consider R-values. Fiberglass batts for standard 2-by-4 walls are available in low, medium and high-density products that range from R-11 to R-15. Sprayed-foam insulation in the same wall cavity can range from an R-14 to an R-28, depending on the product used.

    Read, “Everything You Need to Know About Insulation’s R-Value” to learn more.

    Editorial Contributors
    avatar for Danny Lipford

    Danny Lipford


    Danny Lipford is a home improvement expert and television personality who started his remodeling business, Lipford Construction, at the age of 21 in Mobile, Alabama. He gained national recognition as the host of the nationally syndicated television show, Today's Homeowner with Danny Lipford, which started as a small cable show in Mobile. Danny's expertise in home improvement has also led him to be a contributor to popular magazines and websites and the go-to source for advice on everything related to the home. He has made over 200 national television appearances and served as the home improvement expert for CBS's The Early Show and The Weather Channel for over a decade. Danny is also the founder of 3 Echoes Content Studio, TodaysHomeowner.com, and Checking In With Chelsea, a décor and lifestyle blog.

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