Why Mobile Homes Get Hot & Humid: 9 Causes (Solved!)

Heat in combination with humidity is an uncomfortable and potentially deadly combination.

Is living in a mobile home more likely to expose you to heat and humidity, and what can you do about it?

Regardless of the impact of global warming, certain states have more days with excessively high heat and humidity than others.

If you live in one of those areas, you can expect to suffer in the heat, but is living in a mobile home worse for heat and humidity than other housing?

All homes suffer from a hot, humid climate, but people who live in manufactured homes are more aware of the issue.

why mobile home hot and humid

Why Do Mobile Homes Get Excessively Hot?

In the summer, everywhere is hot—the primary cause of your mobile home heating up in the summer is hot weather.

The primary causes of overheating in your mobile home are:

  • Insulation issues.
  • Poor thermal efficiency.
  • Issues with the HVAC system.
  • Hot weather.


Insulation keeps your house cool in summer and warm in winter because it reduces thermal energy transfer through your walls, floor, and roof.

Manufacturers follow the HUD code and put the specified level of insulation in the roof, belly, and walls of your mobile home before delivery.

But there are different climates in the US, and the HUD code specifies the level of insulation appropriate to that climate.

Depending on where you live, you can regularly experience:

  • Cold or freezing weather.
  • Mixed temperatures with humidity.
  • Hot and humid.
  • Hot and dry.

Putting a manufactured home intended for one zone into another can result in a sweltering or freezing mobile home that doesn’t meet the local climate conditions.

Older mobile homes (Pre 1976 HUD code) won’t have the level of insulation and provisions for modern standards unless extensively remodeled.

If undisturbed, insulation materials are good for 70-100 years before they start to deteriorate.

But Your insulation can fall off the supports around 10-20 years. Any remodeling work can also compromise it.

Suppose you haven’t had a problem with excessive heat in your mobile home and suddenly get issues after a decade of comfortable living. In that case, you may be experiencing an exceptional heatwave or have compromised insulation.

Thermal Efficiency

Heat flows from hot to cold.

The hot air outside tries to come into the cooler air inside your air-conditioned mobile home through any air gaps around your windows, plumbing, or other areas with damage.

You need controlled ventilation, but leaky spaces are not best for keeping you cool as this is an uncontrolled inflow of air.

Heat also transfers through solid surfaces – your windows.

Heat gain or loss through windows accounts for 25-30% of the money you spend on cooling or heating your home.

You need energy-efficient windows to reduce your energy bills in summer and winter.

HVAC System

Remember Goldilocks and her goal to get things just right?

Neither too large nor too small, but the correct size for the purpose?

When it comes to HVAC systems in mobile homes, you need the Goldilocks approach – neither too large nor too small; pick the correct size for your space.

You can get problems with:

  • Not hot or cold enough if too small.
  • Excess humidity if too large (insufficient running time to condense out the water vapor).
  • Frequent repairs if either too small (running all the time) or too large (switching on and off frequently).
  • Higher energy bills.

Problems with your system like a broken sensor, thermostat, or buttons may leave your heating system permanently on, resulting in higher heat in your home.

Failure to maintain and clean your air filters means you don’t benefit from the air conditioning, and refrigerant leakage results in air conditioning failure.

Summer Heat

The hot summer sun heats everything, but the effect worsens when your mobile home has no shade and is constantly in full sun.

The sun beating down on your mobile home is like heating a pan on the stove – the contents get hotter.

Scorching seasons depend on where you live, and you need to crank up your air conditioning to the max to stay comfortable inside your mobile home.

But you can run the air conditioning more effectively if you attend to the other insulation and energy efficiency issues.

What Causes Excess Humidity in Your Mobile Home?

Heat and humidity often go together, sometimes because of the climate, and occasionally your lifestyle contributes.

Humidity makes you feel hotter and more uncomfortable.

Inside your mobile home, the excess moisture can come from:

  • The climate – you live in a hot and humid state.
  • Wrong size HVAC – the air conditioning system needs to run for a reasonable length of time to dehumidify and cool your mobile home.
  • Daily activities without adequate ventilation – such as cooking and showering.
  • Poor air circulation inside the mobile home and in the crawlspace.
  • Absent or damaged vapor barriers.

The steps you take to deal with excess heat can also help reduce your humidity levels if you plan to tackle both issues together.

How Best to Cool Your Mobile Home?

An energy audit can help you establish the most effective areas to tackle in pursuit of a cooler, fresher home with lower energy bills for cooling and heating.

The areas to tackle include:

  • HVAC system.
  • Insulation and vapor barriers.
  • Windows.
  • Ventilation.
  • Dehumidification.
  • Lifestyle.

HVAC System

Check you have the correct size HVAC system for your mobile home – better efficiency and cheaper bills.

After you know you have the right system keep it in tip-top condition by regularly cleaning and replacing your air filters (monthly in hot weather), checking refrigerant levels, and regular servicing to identify and fix any issues.

Insulation and Vapor Barriers

If your mobile home is an older model or you have been living in it for ten years or longer, consider upgrading your insulation and adding appropriate vapor barriers to cut down the flow of moisture into your home.

Pay special attention to the belly of the mobile home, as this area can suffer pest damage.

Metal roofs are typical, but if you have a metal roof, you want the highest level of insulation.

If the interior face of your external walls feels hot to the touch in summer and cold in winter, you can detect places where the insulation is inadequate.

You may choose to upgrade your insulation in one exercise or as part of a maintenance and renewal program.


Double glazed windows are more energy-efficient than single glazed, but there are other steps to reduce the heating impact of your windows in your mobile home:

  • Install heat reflective film on the inside of your windows.
  • Use blackout blinds or drapes and keep them closed in hot weather.
  • Install shutters on the outside to block out the sun or stormy weather.
  • Add awnings above the windows to shade them from summer heat and glare.
  • Repair any issues with cracks and leaks around your windows.
  • Consider replacing the window glass with thermal glass.

Increasing the thermal efficiency of your windows keeps you cooler and saves you money.


Your mobile home needs regular air changes for you and your family to remain healthy.

Stale air from inside your mobile home is exchanged with fresh air from outside through vents and extractor fans. Check you have sufficient vents to achieve proper airflow and ensure they are clean and free from blockages.

Consider increasing the ventilation vents in your skirting as the crawl space can trap moist, humid air underneath your mobile home.

It may seem counter-intuitive on a cold winter’s day or a hot summer day when you are running the heating or air conditioning but consider forcing a daily air change by opening all the windows and doors to push a bulk air change through your home.


Your air conditioning system also acts as a dehumidifier as it condenses water on the cooling coils.

You may wish to consider extra dehumidification in some climates or deal with your bathroom and kitchen moisture.

Dehumidifier units are inexpensive to buy and operate, and running one in your bedroom can make all the difference for a restful night’s sleep free from excess humidity.

Regular dehumidification of your home can reduce problems with mold and mildew because it removes excess moisture from the air before it can condense on your walls and windows.


There are some changes to the way you live that can help cool your mobile home.

These include:

  • Replacing older appliances with more energy-efficient ones – some appliances emit heat in operation.
  • Not using the oven during the hottest part of the day – switch to outside barbecues to keep cooking heat outside.
  • Keeping the curtains or blinds closed.
  • Run extraction fans or a dehumidifier after showering or cooking.
  • Add shade with canopies around your mobile home.
  • Install solar panels to run your cooling systems and heat your water.
  • Consider a green roof for cooling.
  • Consider adding mobile home-height plants on the side that faces the hot afternoon sun.
  • Dress for the heat and stay hydrated.

Your habits can make a difference in how hot and humid weather impacts your enjoyment of your mobile home.

What About Cold Weather?

A vacuum flask keeps hot drinks hot and cold drinks cold.

The same applies to keeping your mobile home cool in summer and warm in winter—all the actions you take to reduce heat and humidity work for minimizing cold and condensation.

Your HVAC system creates a comfortable microclimate inside your mobile home.

Outside, the temperature is either hotter or colder than the interior of your manufactured house.

Thermal efficiency reduces the flow of heat either into or out of your home. That keeps you cozy in winter (for less money) and cool in summer.


If you feel that you have an issue with heat and humidity in your mobile home, you can go over all the points that contribute to excess heat and adapt your home to provide a cooler habitat for you and your family.

A professional energy audit will cover all these points and give you a tailored cost comparison of effective solutions targeted to your manufactured house.

Current climate conditions show more frequent extreme weather events, from high heat and humidity to exceptionally cold.

Acting to ensure your home is a cool sanctuary during the hot weather makes you and your family more comfortable in those hot, humid summer days and nights.