Maintaining the integrity of a roof is the most important aspect of protecting a home from the elements. Roof leaks left unaddressed can cause tens of thousands of dollars of damage. In this article, I’ll talk about basic repairs, what you need, and how they’re done.
If you have an old roof, a leaky roof, or a roof that needs an inspection, our recommended roofing companies are available twenty-four hours a day to address your needs:
- Inspect your roof to find the source of the leak. Check in the interior, attic, and roof itself.
- Remove damaged shingles by gently prying loose the tar strips, then pulling up the nails. When you put down the new shingle, apply sealant to any damaged areas and along the tar strips.
- For flashing, carefully remove it. Then use the damaged piece as a reference to cut and bend a new piece of flashing. Fix it to the roof in the same way as the old piece.
- For cracks and small holes, apply sealant.
- If the job is beyond your level of knowledge and confidence, contact a roofing professional.
A minor roof repair is within the ability of most homeowners. Replacing a few shingles or a piece of flashing takes no more than a couple of hand tools and an hour’s time. If you’re not confident, don’t be bashful to contact a professional roofer (see our guide on how to find the right roofing contractor). If you do decide to tackle the project though, even if it’s a small one, be sure to familiarize yourself with proper roof and ladder safety.
Below, I’ve detailed five easy steps to repair or deal with the most common roof issues:
First, assess whether there is any visible roof damage. Visually examine shingles, gutters and roof edges, flashing around chimneys and dormers. Leaks don’t always come from obvious damage, but starting with the obvious things and moving to less obvious things is an efficient process.
Next, inspect the interior, identify where the water is manifesting, and trace it back to the source. Look for dripping water, water stains, pooled water, sagging, and dampness. It’s best to look for drips while it’s raining. You can use a hose in a pinch, but it’s not an ideal method. A leak can begin in a completely different section of the roof than where it manifests, and some leaks are fickle and only leak when there’s been a sufficient amount of water on the roof.
When you find a leak, access your attic to find where the water is coming in through the roof deck. For this, all you need is a flashlight. Check around all the rafters for any sign of water. Because of gravity, it’s common for water to travel down the roof decking and rafters and drip in a different spot than it’s coming in. So, if you find water dripping, make sure to track it back to the source.
This video from Today’s Homeowner shows you the process of identifying the source of a leak.
What tools you’ll need to do the repair depends on the particulars, so I’ll give you a mostly complete set of roofing tools. Don’t worry, most roofing tools are hand tools, so it shouldn’t break the bank even if you buy all of them. Moreover, they’re general tools that have uses all over the house.
- Roofing hammer for everything that needs to be pounded, broken apart, or “coerced.”
- Pry bar for prying and leveraging sheathing, flashing, drip edge, and more.
- Nail puller. The preferred nail puller for most roofers is called a cat’s paw.
- Utility knife for cutting underlayment and even shingles. I suggest a dual-bladed knife with one side being a hook-blade (useful for all kinds of things, not least of all, cutting and paring shingles.)
- Shears are handy for neatly cutting shingles, like the ones at the end of a course.
- Tin snips for cutting flashing. Most roofers prefer aviation snips. They come in a left, right, and neutral orientation. Any type is fine.
- Handbrake, properly sheet metal handbrake, for bending metal flashing.
- Tape measure for all measurements and layout work. 25′ is standard.
- Chalk box. Great for snapping reference lines and general layout work.
- Roofing nails are commonly called “roofers.” I would go with a 2″ nail. A lot of roofs don’t need 2″, but no roof will suffer for it.
- Speed square for quick, square cuts.
- Pencil for any notes or markings.
- Caulk gun, 10 oz.
As for material:
- Roofing sealant. Any kind will do, just ask around at your preferred big box store for what they recommend.
- Shingles. You’ll probably want ones that match, but that’s not strictly necessary.
- Aluminum coil stock for flashing work. Most box stores have a couple of different colors, so whatever matches.
Replacing a missing shingle is a straightforward process. But we need to understand some things about shingles first. (For the sake of simplicity and brevity, I’ll only address asphalt shingles roofs. Other types of roofs and roof shingles, like wood shakes or flat roofs, have different processes and methodologies, so I’ll leave them for another time.)
There are two halves to a shingle; the half overlaid by other shingles and the revealed half. Importantly, each half of the shingle is fixed to the roof in a particular way.
The top, hidden half is nailed to the roof along something called a nail strip. This strip is near the center of the shingle and, as the name suggests, is where you drive the nails to secure the shingle to the roof.
On good quality shingles, this strip is marked by a fabric tape (often printed with a brand or other indication. GAF, for example, prints SureNail on its nail strips.) You drive the nail through this fabric tape (don’t peel it off.) The fabric tape aids in preventing the shingle from being torn from the nail (which sometimes happens during high winds and other weather events.)
The bottom, revealed half, is fixed to the roof with a tar strip. The bottom half of the shingle overlays the top half of the shingle below it, and this tar strip is what “glues” them together so that water doesn’t get between them and the wind doesn’t blow them up. Unlike the nail strip, you don’t need to do anything with the tar strip. It will naturally adhere over time as the sun heats the shingle and causes the tar to soften and get sticky.
Now that we know how shingles are fixed to the roof. How do you replace them?
The first thing to do is un-stick the tar strip. This can usually be accomplished with gentle prying, either with a tool or your hand. This is easier and cleaner to do on a hot day, but it can also be done on a cold day. If the tar strip tears granules off the lower shingle when you’re pulling them apart, don’t worry; you’ll apply roofing sealant when you put the shingle back or replace it with a new one, so that will compensate for the lost granules.
Next, you need to pry up the nails. Just dig the fork of your nail puller under the head of the nails and pop them out. Since you’re replacing the shingle, don’t worry if you mar it. It’s going in the trash anyway.
Once the tar strip is broken free and the nails are up, the shingle is free, and you’re ready to grab a new shingle and put it on. Just align the new shingle to the surrounding shingles and nail it down along the nail strip. Now, you’re good to go.
Remember to apply sealant along the tar strip on the underside either before or after you nail it down, even with a replacement shingle. Un-sticking two shingles always slightly damages the remaining one, so it’s good practice to apply sealant out of an abundance of caution.
That’s it. Your shingle is replaced, and the roof is water-tight again.
If you’re replacing shingles, take one off your roof and bring it with you to the store. That way, it’ll be easy to find a replacement shingle that matches the style and color. If you’re getting a new roof, ask the company to buy an extra bundle of shingles in case you need a replacement shingle down the road.
Flashing is metal that’s (often) hand-bent to fit the application. Repairing involves simple steps: remove, re-bend, and replace.
First, locate the damaged flashing and begin the process of removing it. Flashing is often interleaved into the course of shingles, so removing shingles or un-sticking them is often required. Flashing is fixed to the roof through a combination of nails and sealant. Sealant can sometimes be overcome by prying, but sometimes you need to utilize a knife to cut the flashing free. Be careful and always cut away from yourself.
Once the flashing is removed, take note of the size and shape. If the flashing didn’t cause the leak, use it as a pattern to form a new piece. Grab some coil stock and shears and cut the blank from the coil. Then use your sheet metal handbrakes to bend the metal into the shape of the old flashing. When that’s done, you’re ready to reattach it.
To reattach the flashing, mimic how the prior flashing was fixed to the roof. This might be nails or sealant, or both. Either way, simply do what the last roofers did. If that’s not possible, no problem. The most important thing to know is to never nail flashing where it might be exposed to water. The area where nails are used should always be covered by something else, shingles, siding, or other flashing pieces. Once it’s nailed in place, decide if you need sealant. Unlike nails, sealant can go anywhere, so apply it wherever it makes sense. Roofing cement is another option. It’s like sealant but thicker and can even be used to encase a piece of flashing.
The sealant is easy to use. The hardest part to remember (something I even have a habit of forgetting to do myself) is that you need to “poke” it. Inside the tube, beneath the spout, a thin aluminum membrane has to be poked through for the sealant to come out. Just shove a nail down the spout and work it around.
Once the sealant is ready, load it into a caulk gun, and you’re ready to start sealing. The sealing itself is simple, just point and shoot. The worst that can happen is you create a bit of a mess, but a mess is a cosmetic issue – it won’t affect the integrity of your roof. Find the crack or hole and squeeze sealant into it until it’s filled or covered. After that, you’re done. You can cover it with shingles or flashing and move on to something else. The sealant will dry in a couple of hours and be completely set in 24 hours; it doesn’t require any intervention after application.
Make sure the roof sealant fits your caulk gun. Some construction materials, like sealant, come in 28 oz tubes that won’t fit a standard 10 oz gun.
The best way to prevent leaks is to maintain a healthy roof. Keep an eye out for any damage, repair any damage you find promptly, clean any lichen and moss buildup, and keep it free of debris. While I wouldn’t say regular inspection is absolutely necessary, I would also say it doesn’t hurt.
Another key aspect of protecting your roof is maintaining trees near the house. Ensuring your trees are healthy and well-maintained will decrease the risk of shedding branches, which might fall onto and damage the roof.
Read also: Methods for Removing Moss from Roofs
Roof repairs beyond replacing a shingle or two are probably best left to a roofing contractor. Many interactions happen between materials in a roof system and between the roofing systems and the other systems of a house.
This doesn’t mean you strictly shouldn’t do it yourself. It certainly can be done well, provided the homeowner has taken the time to educate themselves on how to properly fix the problem. But there’s confidence and certainty that comes with professional work. At the end of the day, minor repairs by a professional are very reasonably priced ( see our article on roof repair pricing).
Most homeowners would likely be happier to have someone else do it, so they can have confidence in their roof and avoid taking unnecessary risks, like working on a roof.
Because of the number of resources available to homeowners these days (guides, videos, books), minor to moderate repairs are certainly doable. It’s not a project for everyone, though. It’s hard work and comes with plenty of risks from heat and falls.
For homeowners on a tight budget, sometimes it’s necessary to roll up your sleeves and get your hands dirty, but if you have the means, I think you’ll be more satisfied and confident to have someone else do it.
Regular roof inspection is very necessary for every homeowner. Check out our roof inspection guide for all you need to know about roof inspection.
For anything beyond a small repair, I would strongly recommend hiring a professional.
FAQs About Roof Repair
What is the best way to patch a roof?
The best way to patch a leaky roof is to identify where it’s leaking, assess if it has caused any interior damage, then repair the problem.
Is patching a roof a good idea?
Always. Water can cause extensive damage to a house. Left unaddressed, it can mean expensive and extensive repairs.
How long does it take to repair a roof?
For minor leaks, a few hours to a day. For anything larger than that, it could be a couple of days to a week (in the case of a full replacement.)
What is the most important consideration when repairing a roof?
In the case of DIY, the most important consideration is whether you’re confident that you know how to correctly repair the problem or not. If you’re not, call a professional.