How does flashing work in roofing

There are other types of premade flashing that are not made to be used on roofs and may break if you try to install them on a roof. For example, head flashing or cap flashing protects doors and windows from water. Typically, by 8-inch mm x mm flashing is chosen. Those 8 inches are more than enough to cover the exposure of typical shingles. In the past, roofing professionals would use lead, or lead-coated materials, as flashing. However, roofing professionals in North America now prefer other materials:.

Building codes may demand your roofing professional use a specific material for flashing. They may also list a minimum thickness. Most building codes require gauge galvanized steel as a minimum. In fact, if you live in Florida, you may find that your building codes call for a special flashing material, modified bitumen roofing tape:. When you install roof flashing, you will need to use a sealant. While roofing professionals occasionally use nails when flashing, they must choose whether to nail to the roof plane or the vertical wall.

If nailed to both, the flashing may deform under the pressure from shifting brick or wood. When nailed only to the roof plane or vertical wall, the flashing can stay in place while the other building materials expand and contract throughout the seasons. Roofing cement : Roofing cement creates a waterproof seal.

Roofing professionals usually apply it with a trowel. Before you learn how to install roof flashing, you need to understand that there are three primary techniques, each suitable for different areas on the roof. Disclaimer : Roof flashing should always be installed by professional roofers, who understand best practices, safety requirements and the building codes and laws in their area. These instructions are only to help homeowners understand what to expect from their roofing professional. Step flashing is the most time-consuming of all flashing jobs on the roof because you must complete it step-by-step as you shingle up the roof.

There are a few general best practices you need to know. First, step flashing must be installed before the siding, so that the siding can cover the top of the flashing. If this is a repair job, the siding must also be removed and replaced with the flashing. Also, before you start installing your flashing, you need to look to see if the wall in question has a corner on the roof face, as in the image below.

If it does, follow our first installation procedure. If a wall corner is on the rooftop, you will need to create a corner flashing piece using a typical step flashing piece. These instructions will tell you how to create a corner piece and how to install step flashing generally:. Instead, you will need to install kickout flashing to help guide the water into the gutter.

Instead, buy a premade kickout flashing piece. Chimney flashing should be installed at the same time the mason is laying the brick and mortar, or the roofer will have to cut a ridge out for the counter-flashing. Then, the roofer will have to seal this indent up, after placing the flashing. Installing a roof plumbing vent is typically an easier task than flashing a chimney.

Here is how you do it:. Do you need information about how to install the other kinds of roof flashing? IKO has already explained how to install drip edge flashing and how to install metal valley flashing. On a typical re-roofing job, where you are replacing an old or underperforming roof, it is wise to replace all flashing. However, there are limited circumstances where a roofer may decide to reuse flashing. For example, if a roofer is doing a repair job on a relatively new roof and the flashing appears to be in good condition, it may be salvaged.

To decide whether or not your flashing can be reused, your roofer will need to remove the flashing carefully to prevent damaging it.

Your roofer will then inspect it before deciding to reuse it. If your roofer is replacing the shingles around your flashing, the flashing must be removed, at least temporarily, to allow for proper installation.

Some types of flashing, like step flashing, may be more challenging to reuse because it is harder to separate from the old shingles without denting or otherwise damaging it. Typically, a roofer will replace step flashing on a new roof. Also, your roofer should not layer new flashing on top of the old flashing.

You should only have one layer of flashing on a roof at a time. You might also wonder what damaged flashing looks like and when it should be replaced.

Check over your flashing and look for:. That depends on a few factors. Kickout flashing is required regardless of the roofing material excluding brick or concrete block. Yes, there can be several factors that can lead to rainwater intrusion, but a missing kickout flashing, in particular, often results in concentrated areas of water accumulation and potentially severe damage to exterior walls.

If you happen to find saturation and possibly plant growth on the exterior siding of your home, you may have missing kickout flashing causing the water damage. Apron flashing is the metal that covers the transition between a roof slope and a roof penetration such as a dormer or chimney.

Having this flashing properly installed is crucial in protecting some of the most vulnerable areas of your roofing system. Apron flashing is usually applied as part of the two-piece roofing system.

The apron is the lower L shaped piece that replaces the normal step flashing, which covers the roofing material and extends up the vertical surface of the roof penetration. Now that you have had a breakdown of the important role that roof flashing plays when it comes to the protection of your roof, it is easy to see why it is needed on almost all roofing projects.

Without roof flashing, our roofs would be much more susceptible to water damage, costing homeowners thousands of dollars in repair or replacement. So when having your next roof inspected or installed, be sure that your flashing is properly installed by your local roofing contractor to ensure the best protection for your roof. Your email address will not be published.

What is Roof Flashing? Roof flashing installation occurs throughout your roof, including all of the following places: Valleys and Joints — the joints found throughout your roof structure are more susceptible to penetration from water, as are roof valleys. The roof flashing ensures that these critical areas of your roof are protected. Think of drip edging as a specialized roof flashing at the edge of your roof that acts as guides to prevent water from getting behind gutters and ensure that all water is directed away from your roof.

Chimneys — Chimney flashing is necessary since water can run through and collect right at the base of a chimney.

Chimney flashing should be installed at the base of your chimney to keep water from infiltrating the joint between your roof and your chimney. For instance, you probably have drain-waste vents which keeps the pressure from building up in your plumbing. These pipes can compromise a waterproof roof if they are left unprotected. Kickouts — Kickout flashing is installed at the lowermost joint between your roof and your wall.

The kickout flashing, also known as diverter flashing, diverts rainwater away from your wall and into your gutter to avoid any kind of saturation leaks in your roof.

Counter Flashing For starters, counter flashing is only one type of flashing and is a technique that is used to help prevent moisture from penetrating into a home behind the vertical flange of a headwall or sidewall flashing. Counter Flashing. Drip edges prevent water from seeping under roofing along the edges of rakes and eaves. Skylights often have their own integral flashing. Otherwise, their curbs are flashed with continuous flashing along the base, step flashing up the sides, and saddle flashing across the top.

Step flashing steps up a roof to protect where the roof meets the side walls of dormers, chimneys, and some skylights. It consists of a series of right-angled metal pieces; each section is worked into a course of shingles so that it overlaps the section beneath it. Valley flashing protects the valleys where two roof planes meet. Before roofing contractors can install aluminum, they coat it with masonry and concrete to prevent corrosion. Copper is malleable and is easy to solder.

It is a highly durable material with a long lifespan. However, as copper ages, it fades into a patina. Steel is the primary choice for flashing. It is malleable and aesthetically appealing. To prevent corrosion, it is galvanized. If you need your roof flashing inspected, fixed, or installed, Southern New Jersey homeowners can contact High Point Roofing at for a free quote. Hit enter to search or ESC to close.

Blog Roofing What is Roof Flashing? The Critical Areas of Your Roof that Require Flashing These areas include: Side walls and front walls the roof surface that joins the wall Valleys low points where two roof slopes join Roof protrusions bathroom vents, kitchen vents, and skylights Roof edges eaves and rakes Even though there are several types of roof flashing, there are four main types of roof flashing you need to know more about.