Most houses are not very well insulated in general, especially older buildings. If you have a room in the house with an above-average amount of heat compared to the rest, several possible issues could lead to this problem.
Why Is My Room So Hot Compared to Rest of House
Clogged Air Filter
If your heat is coming from a forced-air furnace system, then your air filter may be clogged. A dirty air filter dramatically reduces the airflow of the heating system. If this is not resolved soon, it can cause the room to be uncomfortably hot compared to other rooms.
Oversized AC System
If your air conditioner is always on and not cooling the house down, then it may be too large for the square footage of your home. When this happens, the AC system will turn on frequently to keep cool only in some of the rooms in your house while other rooms get extremely hot.
Old, Inefficient Windows
If your windows are old and drafty, then you will likely have a hot room as whichever room faces the sunlight will constantly heat the sun. Even worse is if you buy cheap windows as they do not insulate and more expensive windows.
A faulty thermostat can cause one room to be abnormally warm. If the thermostat is turned down too low or off, it won’t sense as well as it should and will not bring cold air into the room. Another possibility is that your thermostat may be set for a temperature different than what the rest of your house is set at.
Windows Receiving Direct Sunlight
Another source of extreme heat could be your windows. If your windows are not closed tightly, the room will be exposed to direct sunlight most of the day, which can raise its temperature by several degrees.
Insufficient Return Air Vents
If the abnormally warm room does not have many return air vents, then it can become overheated. This problem often occurs if you cover up the return air vents with furniture or drapes.
Hidden Air Flow Paths
If your house has hidden airflow paths behind walls or under floors, then an otherwise standard room may become warmer than the rest of the house. This is especially common when your home was built before forced air heating systems were designed.
Closed Air Vents
If you have a small room that is closed off from the rest of the house, it will stay warmer than the rest of the home. This problem is prevalent if you use your basement for storage or your kitchen has been converted to a bedroom.
Humidifier Set In Room
A humidifier can make a room considerably hotter than the rest of the house and should be placed in a central location to prevent this.
Poor Home Insulation
If your home is not well insulated to begin with, then it will be harder to control the temperature. Insulation is significant if your room faces the sun most of the day.
Abnormally Hot Weather
If it is abnormally hot outside, then everything in your home will be warmer than usual. This includes the floors, walls, and rooms around you are constantly heated by sunlight.
Electronics and Appliances
If some electronics or appliances use electricity in the room, then their energy usage will cause the room’s temperature to increase. This would be especially true if you left your computer, television, or other devices on while gone all day.
If you have recently had a home addition built onto your house, it may be making one room warmer than the rest of the house. This will especially be true if your additions lack sufficient insulation or if they are poorly done.
Things to do to solve the problem of a room being hotter compared to the rest of the house:
Make sure the AC unit is not too large for your home.
This is especially true if there are rooms in your house that are extremely cold compared to the rest of the house. If this is the case, then you need a smaller air conditioner.
If you have already made sure that your air conditioner is appropriately sized but is not cooling your house correctly, check for airflow problems.
Check the thermostat’s temperature settings.
If you are experiencing very hot or cold rooms that seem to be caused by your thermostat, check your air conditioning unit’s temperature settings.
It may be set at a different temperature than what the rest of your house is set at.
Check your home’s insulation.
If you need to improve the insulation in your home, then work with a professional to give you advice on what can be done to increase it.
This may involve adding more insulation or sealing up any air ventilation paths that allow warm air from other parts of the house to enter the abnormally hot room.
Check for airflow problems behind walls or under floors.
Be sure that all of your hidden airflow paths are not blocked off by furniture or drapes.
If they are, your house will have a hard time cooling itself because no cold air can enter the living space from these places.
Check for humidity
If your house is very humid, you will want to bring in a dehumidifier to help lower the relative humidity levels.
This will make it easier for your home’s air conditioner to cool off the room because it won’t have as much water to evaporate first.
Check for things that generate heat.
Try to limit the number of things in your room that generates heat.
For example, you should cut down on electronics and appliances until you find out what is causing your hot room problem.
Keep all air vents open.
If there are closed air vents, make sure that they stay open and don’t get blocked off.
This will enable your home’s air conditioning unit to better circulate cool air through the room and throughout the entire house.
Get a smaller AC unit.
If you have already ensured that there are no airflow problems and that you don’t have a humidity problem, consider getting a smaller AC unit.
A smaller unit will be less likely to cause the room cooling to be colder than the rest of your house.
Use fans and dehumidifiers
If you don’t like using air conditioners, then use fans or dehumidifiers when in abnormally hot weather.
Also, close all interior doors in your home when it is abnormally hot outside to ensure the air conditioner can cool your home without interference from open doors.
Although several things can explain the very hot room problem you experience in your home, most of them can be solved by using a smaller AC unit or checking to make sure all vents and air paths are clear from obstructions.
If these solutions don’t fix the problem, then you will have to contact a professional to help you locate the source of your hot room problem.