Are you tired of your old skylights? Are they drafty in the winter and let in a ton of heat in the summer? Do they fill your home with a dim, yellowy light? Tubular skylights are so much more energy efficient than traditional skylights and can really brighten your home with natural light. Most of the tubular skylights out there from companies such as Velux, ODL, and Solatube, can be installed by most do-it-yourselfers fairly easily in places where you want a new skylight. However, the installation instructions and procedures don't apply to replacing an existing skylight and doing so requires quite a bit more work both on the inside of the home and on the roof. But, for a slightly more ambitious than average do-it-yourselfer, this project is definitely doable and well worth it!
My husband and I recently decided to replace 2 old skylights in our living room with ODL tubular skylights. Our living room has a vaulted ceiling and the skylights have about a 2 foot "tunnel" from the ceiling, up to the roof. The skylights we are replacing are those rectangular, brownish plastic skylights. We elected to split the project up over 2 weekends. It definitely could have been done in one weekend, but we have a thirteen month old baby and didn't want to coop him up inside all weekend and had to tag-team who was working on the project and who was taking care of the baby.
So, the strategy for the skylight replacement was to acquire all of the materials the Friday before we wanted to start and then wake up early that Saturday morning and head up to the roof to do all of the external work to get the external part of the skylights installed and the roof put back together by the end of the day. Then, on the following Saturday, we did all of the interior work. Both Saturdays were long days; about 11 hours each. This is partly due to the fact that we both couldn't work on the project at the same time and had to wait to do some parts of the project until our baby woke up from his nap. Your situation may be different in many ways from ours, but I just wanted to give you a heads up that while this isn't a very difficult project, it has a lot of steps, so it is fairly time consuming.
Things You Will Need
Tubular skylight installation kit (ODL 14 inch tubular skylights are what we used)
Tools listed in the skylight installation kit manual
Shingles for the roof
An additional tube of roofing sealant to reseal the shingles you will loosen
2x4s for the long sides of skylight tunnel, both interior and exterior
Plywood of the same thickness as is currently used on your roof
Drywall (we used the pre-cut 2 foot squares, 2 for each skylight)
Insulation (we used non-backed R38)
Face mask to protect you from the fiberglass insulation
Step 1On the evening before you start the skylight replacement project, cover the inside of the skylights by tacking a tarp up to the ceiling. This will keep most of the debris from getting all over your house while you finish the external part of the skylight replacement.
Step 2Early in the morning, head up to the roof with your pry bar and remove all of the shingles adjacent to the skylight. For shingles like ours, their are about 6 nails across the middle of each shingle, just under the row above. Additionally, the nails from the singles 2 rows above hit the top of the shingle you are interested in removing. So, the system we used to remove a given shingle was to loosen two rows above it, remove the nails that would hit the top of it, then loosen the row above it and remove the rest of the nails holding it in place. Start with the singles at the top of the skylight and work down.
It definitely pays off to do a careful and neat job removing the shingles. You'll be thankful when you re-shingle around your new skylight.
Step 3Take your pry bar and a hammer or mallet to remove the skylight and all of it's flashing. If your skylights are like ours, they are on top of some 2x4 framing. That framing needs to be removed as well. You should just be left with a rectangular hole in your roof after this step.
Step 4Trim back the drywall in the skylight tunnel so that you'll have space to mount a 2x4 along each long edge of the hole to support a new piece of plywood. With our skylights, the drywall tunnel extended up past the top of the roof, so we needed to cut the drywall back to at least just below the existing roof plywood. We decided to go ahead and cut it back further so that the 2x4s could be mounted directly on the existing rafters instead of on the drywall. If your drywall that makes up your skylight tunnel doesn't get in the way of installing the new piece of plywood, you may want to skip this step.
Step 5Cut 2x4s to fit on the long sides of the hole and affix them to the rafters so that the plywood you will put on top will be flush with the rest of the roof.
Step 6Cut the plywood to fill the old skylight hole and also cut the hole for the new skylight. Then affix the plywood to the 2x4s you installed in the previous step. In our ODL tubular skylight kit, a template was included to cut this hole. We decided to have the new skylights toward the top of the area where the old skylights were since we wanted the new skylights to be high on the ceiling in our living room. Figuring out exactly where the skylights would be on the inside was not crucial since the ODL tubular skylights tubes can be rotated to a variety of angles.
Step 7Place tar paper over the plywood, and be sure to cut the tar paper to leave your new skylight hole open. You can see that this isn't tar paper that we are using. We re-shingled our roof several years ago and this was the ice dam material we used in the valleys and along the edges of the roof. We didn't have any tar paper left over, but we still had quite a bit of this stuff, so we decided to use it for this project. I liked it because it is a lot heavier duty than tar paper and it has a sticky back so it created a good seal along the edges with the existing tar paper.
Step 8Time to re-shingle and install the skylight flashing and dome! Start shingling at the bottom and work your way up to your skylight hole. When you have installed enough rows of shingles below your skylight, affix the skylight flashing per the manufacturer's instructions and then continue shingling around the sides and across the top. Then, use some roofing sealant to re-seal any shingles you loosened and place the skylight dome on top of the flashing and breathe a sigh of relief. The bulk of the exterior work on your skylight is done and your roof is all put back together so that if it should rain, you have nothing to worry about.
For our project, you can see that we couldn't find shingles to exactly match our existing ones, so I interspersed the different ones so that it wouldn't be as noticeable. Also, we didn't install the mirrored tube yet to avoid any issues with the sun reflecting around inside it before we had the inside part done. There is a danger that a sunbeam could be focused and do damage to an area if you don't have the diffuser on the inside installed yet. So, the skylight domes in this picture haven't been screwed into place yet and the mirrored tube is not inside.
Step 9Time for day 2. There are a bunch of steps in day 2, so start early! In our installation, several things happened before I took this picture. First, we have popcorn ceiling in our home (asbestos free), that we are gradually removing. So, we scraped the popcorn off of a border around the skylights and then removed the drywall corner bead from each edge. Then, we trimmed back the drywall inside the tunnel so that the new drywall for the ceiling would be flush with the rest of the ceiling. After that, we cut 2x4s to fit the long edges of the tunnel and mounted them. Finally, we went back up to the roof and inserted the mirrored tube into the skylight flashing. As you can see, there is a lot of light that comes through the mirrored tube! To prevent ourselves from being blinded while doing the rest of the work, we draped towels over the skylight domes on the roof while we finished working on the inside.
Step 10After all that prep work in the previous step, you are ready to install the drywall and get the skylight diffuser in place. To accomplish this in our installation, we first angled the tube coming in from the top to point at the place we wanted the skylights on the inside. Then, we trimmed the bottom tube to the appropriate length and slid it over the top tube. Next, we cut one of our 2 foot square pieces of drywall to fit on the ceiling. We then held it on the ceiling and traced where the skylight tube hit it. After cutting the hole in the drywall, we mounted it on the ceiling, installed the diffuser per the manufacturer's instructions and then attached the tube to it.
You'll notice that there is still a big hole in the ceiling. We planned to do the drywall in 2 parts for a couple of reasons. First, the attic space in this area of the vaulted ceiling is just too tight to work in and the tunnel for the old skylight is still there and would prevent us from accessing the new skylight even if we could get to it. Second, by only putting up half of the drywall, you have space to work in. You can get your head and shoulder up there to trace the exact location of the hole for the diffuser, access the tube to get the seams between the top and bottom tubes taped, and have room to stuff plenty of insulation around the tube.
Step 11OK, time to get the insulation in and the other piece of drywall installed. For our installation, we put 2 batts of R-38 fiberglass insulation in each cavity. We took the first batt and pulled it apart in half lengthwise. We stuffed one half around the right side of the tube and the other half around the left. Then, we took the second batt, folded it in half, and then stuffed it in the open part of the cavity. Finally, we installed the second piece of drywall. With essentially a double-thickness of R-38 in this part of the attic, this is easily the most well-insulated part of our attic.
You'll notice in this picture that we haven't finished taping and mudding the drywall seams and so the installation definitely doesn't look complete. We will be doing that soon when we tackle the rest of the popcorn ceiling in this room. As we've done for the other rooms in our home, we will be taking down the rest of the popcorn, applying knock down texture, and then painting. So, we'll be finishing up the drywall work on our skylight installation in conjunction with redoing the rest of the ceiling so that the final product is consistent across the whole room. For your installation, you'll want to do a good job taping and mudding and then match the texture on the new drywall to your existing ceiling to give you a professional looking installation.
These skylights are also much brighter than they appear in this picture. They are so bright that the pictures I took of them in the afternoon didn't turn out very well because all you could see was the bright circle of the skylight. I took this picture in the evening when the sun had gone behind a tree in the backyard. The ODL 14 inch skylights claim to be as bright as five 100 watt light bulbs and from what we've seen, that appears to be true.
Hopefully the above was helpful to you in planning your skylight replacement. If you are anything like we are, you'll be so happy that you got rid of your old skylights and replaced them with energy efficient tubular ones. We love all of the natural light in our living room and the updated look the new skylights give. Have fun with your project!!
Tips & Warnings
This how-to is specific to replacing traditional skylights with tubular ones in a home that has an asphalt single roof, vaulted ceiling, and a tubular skylight model whose tube angles can be adjusted. A certain amount of know-how with respect to roofing, framing, and drywall work is assumed.