The first thing you to figure out is where you want the skylight to be installed. Try making sketches of the room as this can be helpful to determine which part of the room you want to illuminate with the skylight and where exactly you will have to cut an opening in the ceiling. You can also use 3D computer programmes for the job.
Now you need to choose a place for the ceiling opening. Check the attic to see for obstacles such as electrical wiring, plumbing or rafter assemblies. If you find any of these obstacles, a better idea is to choose a different location for the ceiling opening, instead of trying to get rid of the obstacles.
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To make the cutting process easy, try to come up with an area that is between the ceiling rafters. To do this, locate a number of ceiling rafters with the stud sensor and mark their position on the ceiling.
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Using the marks showing the rafter positions as a reference, draw a boundary of the ceiling opening that you desire to cut.
Using a keyhole saw, start to cut at the boundary that you marked in the previous step. Carefully remove the ceiling drywall. Use a sharp chisel if necessary. You have successfully cut a ceiling opening in which you can install a skylight.
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