Modern roofing is a fascinating branch of the construction industry. The materials and techniques that roofers like the team here at Young Construction use to protect buildings from the elements have come a long way in recent years. Some of those materials, while commonplace, have helped roofers to extend the useful life of the roofs they install by years. One of those materials is roof flashing. It’s an oft-overlooked part of a modern roof but is one that can make or break an entire installation. Here’s everything you need to know about roof flashing and why it’s so important.
What Is Roof Flashing?
Roof flashing is a roofing material that’s used to create waterproof borders wherever there’s a protrusion in your roof. For example, it’s how roofers seal the edges of a skylight or chimney. It’s also used to create channels that safely direct water away from vulnerable areas of your roof.
It’s necessary because the materials used in a roof will expand and contract depending on the outdoor temperatures they’re exposed to. Those expansions and contractions can make it possible for water to enter your home. Since that would place your home at risk of water and mold damage, it’s fair to say that roof flashing plays a critical role in keeping your home safe and dry.
What Is Roof Flashing Made Of?
There are a variety of materials used to make roof flashing. Metals are among the most common materials, including copper, stainless steel, and aluminum. Today, however, you might also come across roof flashing made from plastics or other composite materials.
Copper metal sheet flashing is widely considered the gold standard of roof flashing. That’s because it weathers well, adapts to seasonal temperature changes easily, and remains intact for longer than other materials. That doesn’t mean it’s the only suitable kind of roof flashing, though.
Plastic roof flashing also works well as a cheaper alternative, provided it’s used in the right way. Plastic roof flashing is best used on parts of a roof that aren’t exposed to much direct sunlight. The sun can accelerate the breakdown of plastic, so it can be vulnerable to leakage when installed improperly.
The Different Types of Roof Flashing
Since it’s necessary to install roof flashing on a variety of different parts of a roof, it comes in a few different formats to suit those needs. Here’s a breakdown of each type and what it’s used for.
1. Base Flashing
Base flashing is one of the most common types of flashing found on a roof, and it’s also among the hardest to see. It’s installed wherever a roof meets a vertical surface like a wall or a parapet. Since shingles cover most of it, it’s sometimes only possible to see the portion making contact with the vertical surface it’s up against. Base flashing prevents water from seeping into the roof deck at those critical locations.
Counterflashing is a second layer of protection added to base flashing. It covers the base flashing’s exposed parts, typically against the vertical surface of the joint. Counterflashing covers the fasteners of the base flashing and the base flashing itself. The idea is to make certain that water can’t get behind the base flashing where it meets the vertical surface. Most of the time, the visible parts of a roof’s flashing you assume to be base flashing is actually counterflashing.
3. Step Flashing
Step flashing is a type of flashing used to protect joints along the sloped part of a roof. It’s what you’ll find where a sloped roof meets walls, chimneys, and dormers. It comes in L-shaped sections that install overlapping one another, forming a step-like pattern up the slope of the roof. Since this is another type of flashing that’s often visible, it comes in a variety of finishes to suit a building’s exterior finish.
4. Apron Flashing
Also known as continuous flashing, apron flashing covers the base edge of a protrusion in a roof. It comes in long strips and is primarily responsible for directing water into gutters and away from the base edges of things like chimneys and vents. It’s a critical part of a roof’s design because it helps channel water to removal points that carry it away from the roof.
5. Valley Flashing
As you might have guessed by its name, valley flashing lines the dip created when two parts of a roof meet in a valley. Its primary job is to prevent water infiltration into the roof deck and to form a continuous channel down a roof valley and to a gutter. This gives rain and meltwater a place to accumulate and run off the roof without obstacles.
6. Diverter or Kickout Flashing
Diverter flashing, also known as kickout flashing, is installed at the edge of the roofline in corners where the roof meets a wall. Since gutter systems have flat edges when they meet walls, diverter flashing prevents water from running down the flat surface of the wall in the gap between it and the gutter. Instead, diverter flashing channels water coming down toward the wall back into the gutter, where it will safely drain away from the building.
7. Drip Edges
Drip edges are the type of flashing used to protect the edges of a roof that meet with a building’s gutter system. Like diverter edging, drip edging prevents the infiltration of water into the roof by channeling it into the building’s gutter system. This prevents the possibility of rot at the edge of the roof and the potential for water to seep into the building’s exterior walls.
The Importance of Roof Flashing
Although it should go without saying at this point, roof flashing is one of the most important components of a modern roof. It’s critical in keeping the roof watertight and protecting it from the harmful effects of the elements, including rain and meltwater. Without it, the vulnerable materials that make up the roof deck would fail prematurely, shortening the lifespan of the whole roof.
Also, roof flashing helps to make a roof more airtight, which is quite important to the efficiency of heating and cooling systems. By preventing the escape of conditioned air and keeping outside air from entering the home, roof flashing helps HVAC systems maintain comfortable conditions indoors.
Your Local Roofing Experts
It’s important to realize that roof flashing is only a single part of the complex system that is a modern roof. There’s quite a bit more that goes into designing and building the high-performance roofing that today’s homes demand. The experts here at Young Construction know almost all there is to know about roofing and what it takes to build one that stands the test of time. That’s why we’re the best place to turn when your Mason City home needs a new roof or repairs and maintenance services for its existing one.
Since 2001, Young Construction has offered comprehensive roofing services as well as related services like windows, gutters, and siding installation. We’ve done it all with a focus on delivering top-notch customer service and quality that’s unmatched by the competition.
If your home needs a new roof or repairs to an existing one in Mason City, IA, contact Young Construction today.