When we put an addition on our house about a dozen years ago we sacrificed one of the windows in my son's bedroom. He was about ten years old at the time. We promised him that in return for giving up his window we would "loft" his room by creating a ladder accessible second floor where he would sleep.
We kept our promise. It was a major (for us) engineering feat. We were aided in the design by a close friend who is an architect. The result was that my son's bedroom doubled in size once we removed the ceiling and built up into the attic. I even built a special ladder (out of birch wood) that he could use to get up to his second floor, which was carpeted.
A major feature was the addition of a skylight to replace the missing window. I remember well the day devoted to putting in the skylight. I had not yet taken out the ceiling rafters since I needed to stand on them to reach the skylight area. I had even purchased a special saber-type saw to cut a 2.5'x4' rectangular hole from the inside, through the roof and the shingles. That was a daring move on my part. Cutting a hole in your roof sort of commits you to a course of action, and I remember swallowing several times as I began cutting.
Starting at 10am, I finished at 4pm. And thus a functional skylight was installed.
Fast forward to last year and the seaon's first hurricane to reach the Washington DC area. We had developed a leak, the most common of all skylight problems! I dummied up a short term solution (a tarp) but I knew a more drastic repair would be needed.
This past weekend I finally did something about the leak. I built a scaffolding on which to stand, raised the skylight off its frame and set it up on the roof from the inside, and got to work. I removed the shingles and tarpaper from the area where I believed the leak to be starting, and over Saturday and Sunday, I prepared and finally re-installed new shingles, tarpaper, and roof adhesive. It was a messy job but I have reason to believe that the leak is now fixed. I hope this is true when it decides to rain again!