How to Find & Fix a Leak in a Metal Roof

Man on a ladder waterproofing roof

Metal roofs are rising in popularity with residential and commercial property owners alike, due to their long-lasting durability and high rating for energy efficiency. However, no roof is immune to leaks. Flat and corrugated metal roofs are prone to rusting and weakening at the seams over time, and this can cause rainwater to permeate your roof.

If you have a metal roof on your home, don't panic! Liquid Rubber Waterproof Sealant is the perfect tool for fixing a metal roof leak. In this piece, we'll walk you through every step, from how to find a leak in a metal roof to how to go about fixing it so that you never have to worry about the potential of water damage.

What Causes Leaks in Your Metal Roof?

Although metal is one of the most durable and long-lasting roof materials, there are opportunities for leaks to occur — especially if the roof is old or poorly maintained. There are other factors to look out for as well.

For example, if you live in a humid climate or one with a lot of rainfall, you should expect your metal roof to rust faster. If you move into a house with a metal roof, there's no guarantee that it was installed with the level of quality that would allow you to reap the benefits that a metal roof is intended to provide.

Here are some of the most common sources of leaks for homeowners with metal roofs:

  • Improper installation
  • Issues with fasteners
  • Panel damage
  • Open headwall or flashing
  • Missing trim
  • Loose gutters or downspouts
  • Gaps in seams
  • Rust damage

Liquid Rubber Waterproof roof products

How to Find a Leak in a Metal Roof

If your metal roof is leaking, naturally, you'll want to have it fixed before water damage occurs. The first step is finding the leak. Here are some of the places to look when trying to find the source of the issue:

The Roof Body

A visual inspection may be able to help you detect leaks in the body of your roof, especially if the leaks are major. Check for:

  • Holes from weather or debris
  • Rust damage
  • Missing, loose or overly tight screws
  • Shifted metal roofing panels

Connection Points

Seams and joints are common places for leaks to start due to loosening screws or water buildup. Check for:

  • Missing sealant or tape
  • Loose trim or gaps
  • Missing, loose or overly light screws
  • Misalignment where panels overlap

Roof Openings

Most roofs are built around other ventilation, piping networks, and other systems (skylights, chimneys, etc.), which create opportunities for leaks to form. Check for:

  • Cracked seals on flashing
  • Gaps in trim
  • Rotting sealant

Roof Edges

The edges of the roofline, including where the roof and gutter are attached, are also prone to leaks and should be part of your inspection. Check for:

  • Gutter damage
  • Flashing damage
  • Rotting sealants
  • Cap issues

How to Approach Fixing a Metal Roof Leak

Now that you found the source, it's time to go about fixing the metal roof leak. Before you pick up the phone, call a contractor, and spend thousands on repairs, you should know that Liquid Rubber Waterproof Sealant enables you to do the job yourself without compromising quality.

Step 1: Prepare the Roof

The first thing you'll want to do is make sure your roof is 100% ready to treat. Before you do anything, tighten or replace any loose or damaged screws and fasteners. You want your seams to be as tight as possible before sealing the roof for the best results.

Remove any loose debris off the roof. Many people choose to power wash before applying the waterproof sealant to allow the coat to adhere to the roof the best way possible. If you do this, make sure the surface is completely dry before applying tape or sealant.

Step 2: Fortify all Seams

As mentioned, you won't get the best results with loose or open seams on your roof paneling, flashing, or joists. Lay down strips of Liquid Rubber Seam Tape to cover cracks and seams.

If the gaps in the seams are large, use a metal-safe polyurethane based caulking on remaining cracks or seams, making sure to smooth the material before moving on to the next step.

Finally, apply Liquid Rubber Seam Tape around vents, flashing and protrusions, smoothing it tightly down before moving onto the next step.

Step 3: Apply Liquid Rubber Sealant

Now you're ready to seal your roof and prevent leaks! The first thing you'll want to do is seal the seam tape you put around vents, flashing and other protrusions. Apply a coat of Liquid Rubber Waterproof Sealant on these areas before moving onto larger areas.

Using a brush, roller or heavy-duty airless sprayer, apply sealant in an even coat over the entire roof. You need to apply multiple coats, so make sure you're letting the prior coat dry completely first.

Looking for a colored option? Choose our Liquid Rubber Color Waterproof Sealant, but be careful not to apply colored sealant over the standard black product. Use 1 or the other.

Enhance the Impact of Your Roof Sealant

Liquid Rubber waterproof roof sealants are one of the top-rated products designed to help you repair existing leaks and prevent new ones from getting the chance to form. There are, however, some steps you can take to increase the effectiveness of your project:

  • Use Liquid Rubber Seam Tape, the same tape you used on the roof seams, to patch holes and cracks before applying sealant. 
  • Use a water-based rust primer for areas of significant rust, preventing further rot and damage to the surface of the roof.
  • Be sure to apply sealant in the best environmental conditions. It shouldn't be exposed to heavy wind, rain, or excessive heat or sunlight while it's drying. Try to find a day to apply where it's above 50 F and dry.

Save Time and Money with Liquid Rubber

The longest-lasting roof is one that has been properly maintained — and when it comes to preventing leaks in your roof, easy-to-apply, non-toxic Liquid Rubber products are the best option. Save money vs. hiring a professional and get some well-earned peace of mind from knowing you used the industry's leading sealant to weather-proof your metal roof.

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