Cross ventilation is necessary for all interior settings, a room without cross ventilation will retain stale air and all the bad things associated with it. But cross-ventilation is possible only if there are an inlet and exhaust area for the air. So how can we ventilate a room that has only one window?
To ventilate a room with just one window one has to pull in the cool air from the outside through the window, circulate it through the room, and expel the hot air through the same window. To achieve this you can use any of the eight methods given below.
Here are eight ways to ventilate a room with only one window
- Use a pedestal fan
- Use a window fan
- Keep the door open
- Use a whole house fan
- Use a roof vent
- Install an exhaust fan
- Use a ceiling fan
- Minimize furniture and obstructions
- Use an air conditioner
Don’t say that I didn’t say; keep the window open for the first seven methods, and make sure that the window is closed if you are using the 8th method.
Before going into the details let’s see how a room with one window looks like;
This room has one window and a door. The window always opens to the outside of the house, and the door always opens to the inside of the house.
Use a box fan or a pedestal fan
Using a pedestal fan is an easy and effective way to circulate air through a room. Tower fans are a better option since they usually move more air than standard pedestal fans.
For effective air circulation the pedestal fan should be placed on ethe side of the window at an angle facing the closest wall. Below is a picture of how this setup will look like;
Please excuse my expertness in drawing.
The above setup works better than it would if you placed the fan at the center of the window. The reason is, this window is the only inlet and outlet for the air to move, so placing the fan on one side of the window will make it possible for the air to escape through its other portion.
Also placing the fan at an angle to the nearest wall works better to promote air circulation than it would have if the fan was placed facing the opposite wall.
I have tried this setup myself and this works better than it would if you pointed the fan towards your bed or chair. Definitely you won’t feel much airflow but this arrangement will help to cool the room faster with fresh air from the outside.
You can use a box fan if you need more airflow, however they are noisy and so they may not be the most practical option.
Use a window fan
Using a window fan is not my favorite way of venting a room with one window because these fans cover a part of the window obstructing the free flow of air.
This works just like if a pedestal fan was placed infront of a window.
The window fan can be placed covering one half of the window. The best option is to place it at the window’s bottom half. This is because hot air rises, and so when the fan circulates air this makes it is easy for the hot air to escape through the top half of the window.
As you can see in the above picture the air circulation doesn’t quiet cover the entire area of the room, and this is why I prefer a pedestal fan over a window fan. But this ventilation method is better than having none.
Keep the door open
Keeping the door open is an inexpensive way of ventilation a room with just one window. Having the window as intake and the door as exhaust completes the minimum requirements for cross-ventilation.
Even though this sounds like a good plan there are some problems with this. The first one being, in most cases the door opens to another room in a house. This means that the vented air need to travel through another room to go outside. This makes the ventilation process slower. In addition, you may not want to keep the door open the whole time, especially at night. So while this is a good way to ventilate a room, this is only practical to some extent.
Also, the airflow can reverse its direction, meaning the door can work as the inlet and the window as outlet. So the wind may carry odors from other parts of the house into your room.
Use a whole house fan
Whole house fans are those fans installed within the ceiling of a house which pulles air from inside the house and release it into the attic. They are usually installed in hallways which pass through the center of the house.
A whole house fan works by drawing in cool air through the windows of the house thus removing the existing hot air inside. If the house has an attic shared with the room to ventilate then whole house fans are a good option.
As mentioned before whole house fans are usually installed in the ceiling of hallways, and that is the only point at which it sucks air in. However, there are whole-house fans that suck air from multiple rooms with the help of multiple ducted intake ports. These fans are called multi-room whole house fans. By using such a whole house fan the room with a single-window can be vented easily. However, this is a costly method even though it is very efficient. The good thing is, installing such a whole house fan will better the ventilation of the whole house, so if you are planning on some serious ventilation improvements multi-room whole fans are a safe bet.
Use a roof vent
If the room doesn’t have an attic it can be easily vented using a roof vent. Different types of roof vents are available for this starting from box vents to powered roof ventilators. Using any of these vents can easily circulate air through the room. Since hot air rises, the hot air in the room will rise to the top and will be vented through the roof vents. This will create a slight negative pressure in the room that will draw in the cool air from the outside.
If the room is a small one a static vent like a box vent is the right option. Of the room is large the best option would be a powered roof ventilator which works on electricity or solar energy. This fan can forcibly exhaust air from a large area with ease.
If you live in an area with decent winds you can use wind turbines as well. They don’t consume any energy but they remove more air than a static box went can.
Install an exhaust fan
Another simple way to cross-ventilate a room with a single-window is to use an exhaust fan on the wall. The size of the exhaust fan required will vary with the size of the room. Installed on the wall facing outdoors they can circulate considerable amounts of air through the room.
The downside of wall exhaust fans is the noise. Even though these fans are small in size they can produce enough noise to be annoying during the night. If the room needs only occasional ventilation then these fans are a good choice.
Use a ceiling fan
Using a ceiling fan is another great way to ventilate a room with a window. What a ceiling fan does is that it will circulate air throughout the room. With an open window, the circulating air at times will leave the room to the outside. This will be replaced by the fresh air from outside.
In addition, the ceiling fan will provide a cooling effect so it will be more comfortable to live in the room than when it is whole using any of the other ventilation methods mentioned above.
The CFM required for the ceiling fan depends on the floor area of the room. A larger room will require a large fan and vice versa. Here is a good guide to finding the right CFM for a ceiling fan.
Minimize furniture and obstructions
A room filled with fruniture is less likely to have any decent air circulation since the free movement of air is obstructed. Even if a room has only one window that is enough to ventilate it if it has minimum furniture.
Even though the air circulation will be lower than it would be when some sort of mechanical ventilation is used a single-window can passively let in and out air passively. If the window is facing the direction of wind then this passive ventilation is more than enough to remove all the stale air in the room.
Use an air conditioner
All of the homes in the US are air-conditioned, there is little reason why this particular one window room is not. I am pretty sure there are solid reasons why a room is not part of the house’s HVAC but air conditioning is a good way to ventilate the room as well as to keep it cool.
If the house doesn’t have central air conditioning one can also use a split ac or a window ac. They of course have to be used without opening the window.