Cooling A New Room With A Window Unit: Key Considerations

Posted on: 25 August 2015

Adding on a new room to your home is a great way to obtain more living space, but you might have concerns about how to keep it cool and comfortable. Of course, you could connect the space to your central air conditioner, but this might not be the best option. Installing a window unit is much less complicated and a task you can do yourself. This article examines some of the key considerations to keep in mind concerning cooling a new room with a window unit.  


The size of the air conditioner unit must be appropriate to the size of the room. If the unit is too large or small, it will not cool the space efficiently. Window units are usually sized in British Thermal Units (BTUs). For example, if you have a room that is 100 to 150 square feet, then you will need unit that puts out 5,000 BTUs. For larger rooms, you will need a larger unit that put out more BTUs, according to the California Energy Commission.  

Square Footage  

To determine the appropriate window unit for your space, you need to find the square footage of the room. To do this, take a tape measure and find out the length and width of the room. Then multiply the two numbers together to discover the square footage. A couple of factors other than square footage can come into play as well. For instance, if the room is sunnier or shadier than normal, the size of the unit you require could be affected.   


Installing a window unit is generally straightforward and does not require any special skills with tools. You'll usually just need the following materials:

  • the unit (these AC units often come with the necessary screws/nails)
  • drill and drill bit
  • screwdriver
  • level
  • and weather stripping

You want to keep several things mind during the process, however, to get the best results from your efforts. Make certain that you thoroughly inspect the window before installing the unit. You don't want to place a unit in a window that has rotten wood or needs repair. Choose a window close to the center of the room that receives shade from the afternoon sunlight. Also, window units can be rather heavy, so have a friend or relative help you lift the air conditioner into place. A place like HomeSmart From Xcel Energy could also help you install your unit.

Window units can be a simple and economical way to cool an add-on room. Of course, you have other options as well. To learn more about this topic and get expert help on the best way to cool a new space, contact your local heating and cooling contractor.