Adding a Roof Over an Existing Deck
Often when we build a deck on a house, it only takes a little time in the heat of the summer sun, and we quickly realize it would be nice to have some shade when enjoying the outdoors. 
How hard is it to install that roof over your deck to achieve that oft needed shade? It really depends. If you have a single-story dwelling, then adding a roof may mean you have to build a gable (A-frame) roof and then tie that into your existing roof. That can be a little complex for your Do-It-Yourself project. If you have a 2-story home and you are simply adding the roof to the side of your home, as in our recent project shown here, then this may fall under the category of “doable” for you depending on your carpentry skills. This week I will walk through the steps of building that easier of the two-deck roof pointing out tips that will help to make it as easy as possible.
1.) Check with your local building department and apply for any permits you will need. Typically, you will need a building permit and at least a readable sketch of what your addition will look like. You will have to fill out a few forms detailing what size lumber you intend to use and center spacing. Most building departments will help you with answering those questions as you apply for the permits. Once you have the permits and have worked up a material list go ahead and get your material.
2.) Setting your ledger board. The ledger board is the point at which you will attach your rafters. It will attach directly to the side of your house. You will need to clear space for it by removing the siding. Note where the studs are and mark their locations. You will use those studs as anchor points to secure your ledger board. The ledger board needs to be secured properly in order to support the rafters that will be attached to it. You can’t depend on nails to hold it securely so use either 4” lag screws or I like to use Ledger Loks. This is a newer product that is engineered just for this purpose. Most municipal building departments will accept them instead of lag screws or carriage bolt and for me they are well worth the little extra expense in the time they save on the job. If you put 2 Ledger Loks per wall stud and you can rest easy at night knowing that that ledger will hold any snow load put on it here in central Virginia.
3.) Building the support beam. There are 2 areas that need extra attention because of the weight they will have to support in building your roof. The ledger board attached to your house that supports one end of your roof rafters is the first. The support beam that supports the other end of your rafters is the other. The size of lumber you will need for your beam will depend on the distance it is from the ledger wall. The greater the distance of the span, the bigger the rafter size will need to be and the heavier the beam will need to be. In the job pictured, I was spanning 12 feet and so used 2×8 rafters. The support beam out front was constructed of 3- 2×10’s. The overall length of the beam was 20 feet. A beam that big when completed is pretty heavy and needs good supports. In this case we used four 8” fiberglass composite columns. Each column is rated at 10 tons which may seem like overkill, but considering the weight of the roof and the potential for the occasional heavy wet snow it really is about right. Optimally, one would like to build this beam on the ground and then lift by machine into position. You can build it in place a piece at a time (like I did) even by yourself (like I did) if circumstances warrant. I built temporary supports (3 of them) and then installed the side boards going from the house to be attached to the beam, and then built the beam one or two boards at a time (depending on the weight and how early in the day it was). As I put up each board of the nine, I would end up using, I would attach it to the end board or the previously installed board. When it was all in place, I then used 4 ½” Header Loks to pulled it all together tightly. (Tip: once it is up and tied together it won’t necessarily be straight. You will need to stretch a string down it’s length and then use boards to push and pull it into a straight line. This will help with the next step.)
4.) Setting the rafters. To get the rafters to set flat on your beam and the birdsmouth to fit flush to the outside of the beam you will need to know your roof pitch. I will take a little extra time working out the exact pitch where the rafter hits my ledger board. Once I have that I will tack it up temporarily and then holding it on the beam end, scribe the exact size and shape of the birdsmouth. Once I have that right I use that board as the pattern and make all succeeding rafters the same. (Tip: It is very important that before you start setting rafters, make sure your beam is square to the house.) The rafter end attached to the wall ledger board will need additional support, so use an engineered rafter hanger. This will also make the building inspector happy especially if you fill every hole in the strap with a nail. You should also on the beam side tie down your rafters with an approved “hurricane” clip.
5.) Attach sub-fascia. (Tip: Use a string to mark all the rafter tails at the desired length.) I usually measure out about 10 ½” so that when complete I have about a 1-foot overhang. Using a stretched string to mark your rafter tails will give you a nice straight line. Then cut them and nail on your sub-fascia. Your ready now for decking.
6.) Decking your roof. Most decking is done with 7/16” OSB. Use galvanized 6 or 8 penny nails and remember to nail a consistent pattern of at least 5 nails in the centers and on the edges double that. Remember to stagger your joints so that no adjacent succeeding row of OSB ends up on the same rafter previously used for a joint.
7.) Roof felt and Shingles. Before you put felt or another approved barrier down, make sure and install weather guard barrier to the outer 3 feet of the roof (front edge and both sides). This will prevent water seepage back up under shingles from ice and snow build up on a roof. Follow installation instructions on felt and shingles.
8.) Framing in the gable sides. On the sides from the side boards to the edge of the last rafter, you will need to frame in that area and cover it with 7/16” OSB. Just put your 2×4’s on edge and space them every 2 feet. Cover with OSB and then an approved house wrap. That house wrap is a moisture barrier that you will need for your “veneer” inspection. It won’t pass inspection without it.
9.)Call for your framing and veneer inspections: At this stage call for your inspections. Building inspectors will look for many of the things already mentioned in the above: Proper lumber size, proper spacing between rafters, rafter hangers, hurricane clips, proper ledger fasteners, and house wrap for the veneer.
10.) Finishing touches; Once inspections pass, put on your siding on the gable ends. Put on your fascia board and soffit. The last thing to do it to wrap you beam with trim coil and install a ceiling. I will describe those steps in the next post.
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Caulking 101
Nothing finishes a job around a tub, shower, sink or vanity like a nice, clean professionally applied bead of caulk. The challenge is getting that caulk applied neatly isn’t it? I’ve pulled up many a bead of caulk that looks like it was applied by an 8 year boy. For any of us that have done any caulking at all we can appreciate the difficulty in getting that caulk on neatly. There are several things that I have learned over the years that have much improved my results and can do the same for you as well.
1.) You need a good caulk gun.
Like most things, all caulk guns are not created equal. Some are apparently are just manufactured to resemble a caulk gun in their basic shape. I guess to be fair I ought to add that they also seem to be designed to function somewhat like a true caulk gun as well… in that if you squeeze the handle hard enough caulk will come out.
What I have found that works best is a caulk gun with a spring and sliding tension bar. This design seems to allow you more control of the pressure pushing the caulk out. You don’t want the caulk to come out too fast( that is what causes the lumpy, globby results that look so unprofessional). In fact it is better for the caulk to come out slower than you want than faster than you want. Also, with this kind of caulk gun when you get to the point you want to stop caulking…it is easier to stop the flow of caulk. With a rachetted caulk gun you invariably end up with too much caulk at the end point and/or a spill of caulk on your work you have to clean up later(i.e. more mess and more work). Get a good caulk gun at the start and you will be thanking yourself later.
2.) Cut the tip the right size for the job.
So you’ve gotten a good caulk gun and you are ready to start. How big of a bead do you want? My advice is to start small…smaller even than you think . You can always stop later and cut the tip a little bit more to get a larger bead. Once you have cut the tip too big you are stuck with it… and likely just going to make more work and more of a mess. Start small and work your way up with your bead size.
3.) Keep a moist hand towel close by
Caulking sets up(dries) pretty fast…almost always faster than you think it will. As soon as you get a bead run with the caulk gun be prepared to touch up. Moisten a finger on the towel and lightly run it along the bead. If you have you caulk bead the right size this will do a nice job of smoothing any irregularities and give it that nice smooth finished look.
4.) Keep some paper towels handy too
With practice in cutting you caulk tube tip….you will learn to get that bead the right size and will rarely ever have to wipe excess off. But until you have practiced a bit, you will invariably get too much caulk on in spots. Don’t panic. Simply wipe the excess off with a paper towel , re-apply a new bead and then smooth with the moisten finger.
5.) Get the right caulk for the job
Once after caulking an outside seam and then letting it dry I painted the wood and caulk only to find out that my paint was beading up on the caulk! Some caulks are not paintable. Many are. Many silicon based caulks are not paintable…. though some are. Plan ahead on your project. Will you need to paint the caulk later? If so, take your time in choosing your caulk….make sure it is plainly marked as “Paintable”.
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