How to Fix a Leaking Roof (2023 Guide)

In many cases, roof leaks fall under the umbrella of basic roofing repairs. Depending on the extent of your damage, you may be able to attempt a DIY repair and avoid the hassle of calling a professional roofer. Here, we’ve broken down exactly how to detect leaks, how to attempt simple roof repairs with a step-by-step guide, and how much roof repairs cost.

How to Find a Roof Leak

As a homeowner, the first step towards any home repair is diagnosis. You’ll have to find the exact location of your roof leak before you commence with repairs. Sometimes, this is fairly easy to see from your home’s exterior. If you’ve had a severe rainstorm and debris has damaged your roof shingles or panels, then a simple walkaround of your home may be enough to spot weak points in your roof.

Common points for roof leaks include roof valleys and roofing sections where debris commonly collects. Any flashing along the apex of your roof, under your gutters, and along dormer windows are also prone to leakage.

Beyond external weak points, you may be able to see water damage from the inside of your home in certain instances. Water spots on your ceiling, dripping sounds, wet spots around your fireplace, and more could be telltale signs of a roof leak. If you have a vague idea of where a leak may be, then you could see wet spots in your roof decking from the inside of your attic. You may need to peel insulation away from the damaged area, but most large or small holes should be easy to spot.

How to Fix a Leaky Roof: Step-by-Step Guide

You’ll employ slightly different techniques and processes to repair each major kind of roof. As a home improvement task, handling roofing repairs properly when you first detect leaks is important if you want to prevent further damage.

Asphalt Shingles

Asphalt or architectural shingles can be repaired with simple silicone caulk, but this is never recommended. In most cases, you’ll have to tear away the entire defective row of shingles and secure a new one with roofing nails and caulk. This video from Drew’s Roofing and Home Repair in Southport, North Carolina, gives a fairly concise yet thorough breakdown of the process, which is as follows:

1. Break the seal between the defective shingle(s) and the surrounding ones with your pry bar. Break up any old caulk that has been holding the shingles together while prying up the roofing nails holding it onto the substrate. When prying the roofing nails out, take extra care not to bend the above row of shingles too far out of shape as they could break.
2. Be sure to fully remove all nails from the roof decking. Once all of your shingle’s fastening points are free, remove the defective shingles.
3. Inspect your roof decking and underlayment for damage. If you notice any rot in your roof decking due to long-term water damage, then this will have to be replaced.
4. Place your new shingles directly in line with your existing rows. Be sure to line these up exactly, with the top of your new shingles tucked fully under the row above.
5. Secure your shingles with roofing nails. Place your two-inch stainless steel nails in a perfectly straight line, about one full inch under the edge of the above row of shingles. Space them equal distances apart, and hammer them into your substrate.
6. Caulk along any unsealed lines above and below your new row of shingles. This should form a watertight seal just behind your roofing nails.

Metal Roofing

Metal roofing repairs are somewhat more involved than repairs for asphalt shingles but are within the abilities of many handy homeowners to complete. Here, we’ve detailed a step-by-step guide to fixing a small leak. If you suspect that your roof decking is damaged, or if this repair is in a readily-visible area, you may be better served going to a roofing contractor.

You’ll need a few things to start:

• Power drill
• Aviation snips
• Urethane sealant or caulk
• Self-tapping metal screws
• Wire brush or abrasive steel wool
• Putty knife
• Pencil or marking implement
• Metal roofing panels to match your existing roof

For your small metal roof leak, you should follow these steps:

1. Clean the damaged area with a mild non-toxic household cleaner.
2. Once dry, mark a squared-off line around the affected area. Mark a matching area on the extra piece of metal sheeting you have.
3. Using your steel wool or abrasive substance, scuff up the damaged area of your roof within the pencil line. This scuffing makes for better adherence when you apply sealant.
4. Using your aviation snips, cut your patch from your loose replacement panel.
5. Apply your sealant to the damaged area of your roof. You should spread it up to your pencil line with your putty knife. Be sure of even application.
6. Place your patch exactly within the pencil lines and press it onto your roof. Your sealant should ooze out from the sides of this patch.
7. Using your self-tapping screws, secure your patch to your existing roof panels. The screws shouldn’t penetrate through to your roof decking. Space your screws an inch in from the edge of the patch, about four inches apart.
8. Use your putty knife to ensure uniform sealing of your patch around the edges. Remove any excess sealant beyond the edge of the patch and follow manufacturer directions to allow it to cure fully.
9. If your patch doesn’t totally match your existing roofing, then you can paint it to match.

TPO or Roofing Membrane Patches

Roofing membranes are far more common on commercial or flat roofs, but if your residence has a TPO roof, it should be easy to patch. You’ll need a section of matching roof material, as well as a hot air welder, to complete this roof patch.

1. Clean the area to be patched with weathered membrane cleaner. Exercise caution, as these cleaners are flammable and can have toxic fumes.
2. Cut your patch to size. Any membrane patch should extend beyond the tear in existing roofing by at least two inches on all sides. Round the edges of your patch; this will help to ensure long-term adherence to your existing roof.
3. Using your hot-air welder, adhere your patch to the affected area. For larger patches, a 1.5” seal around all sides is sufficient. For small patches, attempt to create a total seal if possible. Use a roller such as this one to press the roofing layers together while applying heat.
4. Allow your membrane to cool, then check around the edges to ensure that it is totally sealed.
5. Apply cut-edge sealant around the edges of your patch and allow it to dry.

Repairing vs. Replacing a Roof

In many cases, repairs will be more than sufficient. Full-scale roof replacement will not be necessary to ensure the long-term health of your home. For reference, we’ve listed the life expectancies of each major roofing type here:

• Asphalt shingles: 20 years
• Copper: 60 – 70 years
• Slate: 60 – 100 years
• EPDM Rubber: 12 – 25 years
• Metal (average of all types): 40 – 70 years
• TPO: 10 – 20 years
• Wood: 25 – 30 years

Fastest Way to Seal a Roof Leak

The most commonly-used fix for roof leaks involves thoroughly applying roofing cement or silicone caulk. Whether you’re repairing a small leak on a shingle roof or repairing flashing around a skylight or vent boot, you’ll be able to conduct this repair with a caulk gun.

Tips for Fixing a Leaking Roof

Here, we’ve listed a few helpful factors to consider before embarking on any roofing repair. Be sure to consider these before you begin tearing off defective sections of your roof.

Wait for Warm, Dry Weather

Having a roof leak is already bad enough without further lasting damage being done to your roof sheathing or substrate. Tearing down leaking roof sections on a rainy day could lead to your roof sustaining even worse damage, which will require further repairs.

Additionally, conducting repairs in warmer weather — if possible — will make membrane and shingle roofs far easier to work with and bend into shape.

Review Regulations for Prevention of Falling Injuries

Falling injuries are the leading risk for construction workers across the U.S., according to OSHA.

If this is true for properly trained and experienced laborers, it should come as little surprise that your relative risk of injuring yourself due to a fall while roofing is elevated. Be sure to review the following safety regulations for construction workers before undertaking your roofing project. Even though much of this is tailored to professionals, you should find some value here.

Review your Roof Warranty

Most roofing materials and professionally-installed roofs, in general, will come with some form of warranty attached. When you get a new roof installed, you should remember to keep copies of any manufacturer and labor warranties. This will keep you informed on what your financial responsibilities are in the event of roof leakages.

Cost to Repair a Roof Leak

Hiring a professional roofing contractor for a minor repair will usually cost between $175 and $450. Labor costs for such a task will fall between $45 and $80 per hour. You should expect to pay markups for supplies, such as new flashing, new shingles, fasteners and roofing nails, and sealants. Here are a few factors which will dictate your costs if you elect to hire a contractor:

• Size of the damaged area: The larger the area, the more materials and time the job will require. Most contractors will assess the damage before beginning work and give you a cost estimate to help you prepare.
• Roof pitch: OSHA defines any roof with more than a 4:12 pitch (4 inches of “rise” per 12 inches of “run”) to be a “steep roof.” If your roof falls under this category, then your repairs could cost more due to the added difficulty of working in such a space.
• Roofing material: Roofing material costs vary by type and region. Generally speaking, asphalt shingles will cost the least, while copper roofing panels will have the highest per-square-foot costs.
• Secondary roof characteristics: Skylights, dormer windows, vents, and other external features could increase both material and labor costs for your roof leak repair.

Roofing Company or DIY?

Unless you have a single-story home with a low-pitch roof, we’ll always recommend hiring a local roofing contractor to handle your roof repairs. Contacting pros in your area before a home renovation is always a good idea, even if you plan on completing the job on your own. Having an expert appraise the damage could alert you to potential problems that you may not have been aware of when you first detected your roof leak. The simple patches we’ve outlined above are ideal for DIY roofing work but should be done with the utmost care. Rushing through a roof patch could have long-term effects on your roof’s lifespan and home health.

More Roofing Resources