Since the existing light is already connected to the switch and you are not adding a light switch most of the wiring you need will be present in the wall.
How to add another attic light.
To find out first shut off the power to the switch at the main electrical panel.
Then with our instructions and a few hours work you ll be able to add a sconce to any room that has an appropriate switch.
Just inside the entrance to the attic is ideal.
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This technique connects the fixtures in parallel which guarantees that each light will stay on if the other one burns out.
This is a video on how i installed an attic light in the house attic space.
If you think a room in your house is too dark you may want to add an additional wall light fixture.
I demonstrate the light install process including installing a new rough in elect.
Try to place the switch box close to another light circuit which will make creating a circuit for the attic light easier.
After that run a second wire from the other side to where the light will hang.
When you re adding a light to a circuit you use a technique called daisy chain wiring.
Not all electrical boxes with a light switch in them contain the necessary ground hot and neutral conductors.