Roof Flashing in Fort Walton Beach, FL: Where Most Roof Leaks Actually Start

A&M Construction

Nov 2

4 min read

Most roof leaks do not start in the middle of the shingles. They start at the flashing: the thin metal that seals the places where your roof meets something else, like a chimney, a wall, a plumbing vent, a skylight, or a valley where two slopes join. Shingles shed water on their own. Flashing is what keeps water out of the joints where shingles alone cannot. On a coastal roof in Fort Walton Beach, Florida, where salt air, heat and afternoon downpours all work on those joints, flashing is often the first part to fail. A&M Construction of NW Fla has been repairing and replacing roofs out of Mary Esther since 1994 under Florida license CCC1326077, and this is how to tell whether yours is the problem.

Roof damage around flashing and shingles on a home in Fort Walton Beach, FL

The five places flashing does its job

Chimneys. A chimney is flashed in several parts: a continuous piece along the bottom, step flashing up the sides, a saddle at the top, and cap (counter) flashing set into the chimney that laps over the rest. Any one of those failing lets water behind the others.
Side walls and dormers. Step flashing is a series of small right-angled pieces, each worked into a course of shingles so it overlaps the one below. It is installed piece by piece as the shingles go on, which is why it cannot be properly replaced without lifting the shingles around it.
Valleys. Where two slopes meet, a valley carries the runoff of both. It is the heaviest-flowing spot on the roof and one of the most common sources of leaks.
Vents and pipes. Vent pipe flashing is a cone with a flange that sits under the shingles. The rubber collar on many of them cracks in the sun well before the roof itself wears out.
Edges and skylights. Drip edge keeps water from creeping under the roofing at the eaves and rakes, and skylights are flashed with a base, sides and a saddle across the top.

The names and shapes of each type are laid out in this plain-language guide to how roof flashing works, which is worth a look before a contractor walks your roof so you know what they are pointing at.

Signs your flashing has failed

A stain on the ceiling or wall that shows up near a chimney, a wall line, or under a vent. Water often travels along framing before it drips, so the stain may sit a few feet from the actual entry point.
Rust, pitting or white corrosion on the metal. Flashing is usually galvanized steel, aluminum or copper. Salt air speeds up corrosion, and two different metals touching each other can corrode faster than either would alone.
Dried, cracked or missing sealant. Caulk is a short-term patch, not a repair. If the only thing holding a joint closed is a bead of sealant, that joint has already failed.
Lifted, bent or loose pieces. Wind and thermal movement can pull flashing away from the roof or wall, leaving a gap that wind-driven rain walks straight into.
Cracked rubber collars on vent pipes. Easy to see from a ladder, and a cheap fix when caught early.

Storm-related roof damage that often begins at flashing and roof edges in Fort Walton Beach, FL

Repair it or replace it?

A loose vent collar or a single lifted piece can be repaired in a short visit. Flashing that is corroded, undersized, or was installed wrong in the first place should be replaced, and that is a different job than it sounds. Because step flashing is woven into the shingle courses, proper replacement means lifting the shingles around it, setting new metal, and re-shingling the area. During a full reroof the right call is almost always new flashing rather than reusing the old, which is one of the details that separates a roof built to last from one that is merely covered. We walk through the full range of choices in our guide to roof repair options: patch, section repair, or replace.

Flashing also works hand in hand with what sits under the shingles. If you are curious how the layers fit together, read about roof underlayment and secondary water barriers.

Frequently asked questions

What is roof flashing?

Thin, usually rust-resistant metal that is shaped and installed where a roof meets a wall, chimney, vent, skylight or valley. Its only job is to guide water over the joint instead of into it.

Can I just caulk a leaking flashing joint?

Caulk can slow a leak for a season, but sealant dries out and cracks in Florida sun. If the metal itself is rusted, bent, or installed wrong, the real fix is to replace it.

How do I know the leak is the flashing and not the shingles?

Location is the clue. Leaks that line up with a chimney, a wall, a vent or a valley point to flashing. Leaks in the open middle of a slope more often point to shingles or the layers below. An inspection on the roof is the only way to be sure.

How long does roof flashing last?

It depends on the metal, the installation, and the exposure. On the coast, salt air shortens the life of lower-grade metal, so it is worth checking flashing whenever the roof is inspected, not just when something leaks.

Is flashing covered by my roof warranty?

Flashing problems are usually installation issues, so they fall under a contractor's workmanship warranty rather than the manufacturer's product warranty. We explain the difference in our post on roof warranties.

Will a leak at the flashing damage my attic?

It can. Slow leaks soak insulation and framing long before a stain appears on the ceiling, which is why small flashing leaks are worth fixing early.

Have the flashing checked before the next storm

If you have a stain you cannot explain, or you simply have never had your chimney, vents and walls looked at, start with a professional roof inspection. We will show you what we find and put the fix in writing. Family owned in Mary Esther since 1994.

Contact A&M Construction or call 850-803-0650.