Metal is an incredibly durable material. And metal roofs are expected to last at least 50 years or even more.
But they aren’t indestructible or invulnerable. And things happen. These roofs can end up damaged, compromised, and leaking – either before or after the expected lifespan.
If a metal roof leaks within its lifespan, then poor installation work is a likely culprit. This can happen when screws, fasteners, or seams are installed incorrectly, . At other times the product itself is the problem. Or perhaps severe weather or impact damage took its toll.
A metal roof can also start leaking due to old sealant or attachments. Sealants and coatings will eventually expire. Screws, seams, and attachments will grow weaker over time, due to withstanding long periods of expansions, contractions, and roof movement.
Metal Roof Repairs
Possible metal roofing damage includes loose attachments or panels with rust spots, wrinkling, buckling, tears, cracks, and holes. Moisture and leaks can be caused by issues ranging from loose attachments to cracks or holes.
The metal roof repair options include:
- Metal panel patching
- Attachment replacements or fixes
- Metal panel replacement
- Metal roof replacement
Minor issues like rust, cracks, or tears can be repaired with spot treatments and patches. Other issues like larger holes or holes accompanied by buckling should be fixed with a panel replacement. It may also be necessary to reseal certain areas or recoat the roof.
Homeowners should think carefully about taking on this kind of home repair work. Metal roofing might be durable, but it doesn’t hold up to foot traffic well, and so, walking around a metal roof isn’t advised.
Anyone working on a metal roof will need to use a ladder, be comfortable working at heights, understand how to navigate on slippery surfaces, and be familiar with the roof’s underlying structure.
How to Patch a Leaking Metal Roof
- Metal Shears or Snips
- Cordless Drill or Impact Driver with Phillips Head Bit
- Putty Knife
- Caulk Gun
- Emery Cloth or Metal File
- 600-grit sandpaper
- Wire Brush
- Paint Brush
- Sheet Metal for the Patch (that matches the roof’s metal)
- Urethane Caulk Sealant: in the same color as the metal patch
- Paint: sealant-compatible and in the same color as the metal panel being repaired
- Pan Head Sheet Metal Screws
- Residue-Free Cleaner: such as Simple Green
Metal Roof Repair Process:
- Clean the roof
Begin the project by examining and cleaning the damaged section.
First, look to see if any metal roofing is lifting up around the damaged area. The damaged roof might be lifted, curling, jagged, or sticking up. If you see anything like that, cut them off or hammer them down so that the area is completely level.
Then clean the area with an all-purpose cleaner like Simple Green. Use the cleaner to remove any grime, film, dirt, or algae growth. Then wipe the surface again with a wet cloth. Then dry it with a clean, dry cloth.
- Measure and cut a repair patch
Measure the area of the roof that needs repair. Then cut a piece of sheet metal that’s at least 2 inches larger than this on all sides.
Use an emery cloth or metal file to round out the corners and smooth the edges. Make sure to complete this step, as it’s essential for preventing snow and ice from catching on the piece of metal.
- Outline the patch and scuff the surface area
Position the patch over the damaged section and outline around it with the pencil.
After this, gently scuff the repair area’s surface with a wire brush. Scuffing it will help the repair sealant adhere to the metal, but it will also remove some of the roof’s protective coating. So only brush within the area that will be patched and try not to go beyond that.
- Apply urethane sealant
Apply the urethane sealant to the surface area that needs repair. The sealant must be applied along the inside edge of the outline, staying within the first two inches.
The sealant has to squeeze out from underneath the patch, oozing out along the entire edge. Moisture will be able to get into any areas where it does not. So make sure the application is even and generous.
- Put the patch on
Place the metal patch over the damaged area and firmly press it down. Make sure the sealant is oozing out along all the sides. If there are spots where the sealant isn’t coming through, apply more to that section.
- Secure the Patch on the roof
Use the pan-head sheet metal screws to secure the hold. The screws should be positioned around 1 inch inside the edge and spaced out every 3 to 4 inches.
Make sure the screws go down to the underlying roof panel, but no further. Don’t screw into the decking or rafters.
Once you’re finished screwing, use the putty knife to smooth the sealant along the patch so that it fully covers the edges.
- Paint the Patch to Match
Repair patches don’t have to be painted. You can skip this step, especially if the patch isn’t visible or is already in the same color as the roof.
If you do want to paint the metal patch, this step has to be done after the sealant is dry. And you must use paint that’s compatible with the sealant.
First, use the wire brush to lightly scuff the surface of the patch and the roofing that’s right around it. Then paint it.
Professional Metal Roof Repairs
Metal roof repairs are a little more advanced than some other roofing projects. Quick fixes can be done to hold things over, but for long-lasting repairs, it’s best to have this done by a professional roofer.
A local roofing company will first complete a thorough roof inspection to determine the full extent of the damage and evaluate the roof’s integrity. Then they’ll provide you with a report on what’s going on and recommendations for the best repair method.
A professional metal roof repair might cost a little more than doing it yourself, but it’s much less expensive than a roof replacement or interior restoration.