If you are wondering, "What are the parts of a roof called?", the main components include the roof deck, underlayment, shingles, flashing, valleys, ridge, vents, fascia, soffits, gutters, and the rafters or trusses supporting everything underneath. Each piece has its own job, but they all work together to keep water, snow, ice, and wind out of your home. In Wisconsin, where a roof can go from carrying heavy snow in winter to handling thunderstorms and heat in summer, every one of these parts matters.
You probably recognize shingles and gutters, but many of the most important parts of your roof are hidden. Knowing a little roofing terminology can help when you are looking at an inspection report, talking with a contractor, or trying to figure out where a leak might be coming from.
A residential roof is made up of structural pieces, protective layers, drainage components, and ventilation features. The exact setup depends on the home's design and roofing material, but most Wisconsin homes have many of the same basic parts.
These commonly include:
Some of these components are easy to see while standing in the yard. Others will not be visible unless shingles are removed or you look inside the attic.
Before you get to shingles and other exterior materials, there has to be a structure capable of supporting them. The framing and decking give the roof its shape and create a solid base for everything installed above.
Rafters are angled pieces of lumber that extend from the peak of the roof toward the exterior walls. They help form the roof's slope and support the decking and materials above them.
Rafters are common in traditionally framed homes and may be visible when looking inside an unfinished attic.
Many homes use roof trusses instead of individually framed rafters. Trusses are engineered sections that use interconnected pieces of lumber to distribute the roof's weight.
They are usually manufactured before arriving at the construction site and installed as complete sections. While rafters and trusses perform similar jobs, they are not the same thing.
Decking, also called roof sheathing, is attached directly to the rafters or trusses. Plywood and oriented strand board, commonly called OSB, are frequently used for this layer.
The decking creates the solid surface needed to install the rest of the roofing system.
Water that gets through the exterior roofing materials can eventually reach the decking. Over time, moisture can cause sections to soften, swell, rot, or lose their ability to hold roofing fasteners properly.
This is one reason contractors inspect the decking during a roof replacement. Once the old materials are removed, damaged sections can be identified and replaced before the new roof goes on.
Shingles receive most of the attention, but they are not the only defense between your home and Wisconsin weather. Several materials underneath them provide added protection.
Underlayment sits between the roof decking and the shingles. Think of it as a secondary line of defense if water gets underneath the finished roofing material.
Traditional asphalt-saturated felt has been used for decades, while synthetic underlayments are common on newer roofing projects.
Underlayment is not intended to replace shingles. Instead, it provides another protective layer underneath them.
Ice is a particularly important roofing concern in Wisconsin.
During winter, heat escaping into the attic can contribute to uneven snowmelt on the roof. Melted snow may run toward colder roof edges and refreeze. This can contribute to ice dams, which may cause water to back up beneath roofing materials.
Ice and water membrane is a self-adhering waterproof material installed in vulnerable areas of a roof. Depending on the roof and applicable requirements, it may be used near eaves, valleys, penetrations, or other areas where leaks are more likely to develop.
Drip edge is metal installed along roof edges. Its job is to direct water away from vulnerable areas and toward the gutters.
Without proper protection along the roof edge, repeated exposure to rain and melting snow can contribute to moisture problems around fascia boards and roof decking.
When most homeowners talk about their roof, they are usually talking about the exterior material they can see.
On many Wisconsin homes, that means asphalt shingles.
Asphalt shingles overlap one another to create a surface that sheds water toward the bottom of the roof. They also protect the materials underneath from direct exposure to sunlight and weather.
Wisconsin weather can be hard on shingles throughout the year. Snow and freezing temperatures are concerns during winter, while thunderstorms, hail, high winds, and strong sunlight can cause wear during warmer months.
Signs of shingle damage can include:
An isolated damaged shingle may only require a repair. Widespread wear can be a sign that the roof needs a closer inspection.
Starter shingles are installed around roof edges before the main field shingles. They help establish the first course and provide additional protection along areas exposed to wind and water.
Once the roof is complete, you may never notice them, but they are an important part of proper shingle installation.
Look at the highest horizontal line on a typical sloped roof. That is the ridge.
Ridge cap shingles cover the area where two roof slopes meet. They protect the seam while creating a finished appearance along the top of the roof.
Some parts of a roof face more water than others. Valleys, penetrations, and areas where the roof meets another surface need special attention.
A roof valley is the inward angle created where two sloping roof sections meet.
During rain or snowmelt, water from both slopes is directed into the valley. That means a large amount of water can travel through a relatively small section of the roof.
Because valleys handle so much runoff, damaged materials or poor installation in these areas can lead to leaks.
Wisconsin homeowners may want to pay particular attention to valleys during winter. Snow and ice can accumulate in these areas, adding another reason for proper waterproofing.
Flashing is usually made from thin pieces of metal placed around areas where water could enter the roof.
You will commonly find flashing around:
A roof leak does not always mean the shingles are bad. Damaged, loose, corroded, or incorrectly installed flashing can allow water into an otherwise healthy roofing system.
It is easy to focus on the large surface of the roof and forget about the edges. Fascia, soffits, gutters, and eaves all have jobs to do.
Fascia is the vertical board running along the lower edge of the roof. Gutters are commonly attached to it.
Fascia also helps cover and protect portions of the roof structure. If gutters overflow repeatedly or water gets behind them, fascia boards may begin to deteriorate.
Look underneath the section of roof that extends past the exterior wall. The finished material underneath that overhang is the soffit.
Soffits provide a clean appearance, but many also help with attic ventilation. Vented soffits allow outside air to enter the attic as part of a balanced ventilation system.
The eave is the lower portion of the roof that extends beyond the exterior wall.
Eaves are particularly important to understand in Wisconsin because this is one area where ice dams can develop during cold weather. Proper insulation, ventilation, and roofing installation can all play a part in reducing moisture problems near roof edges.
A roof needs to handle moisture from the outside, but moisture and heat inside the home matter too.
Proper attic ventilation allows air to circulate through the attic. Typically, cooler air enters through intake vents near the lower part of the roof, while warmer air exits through exhaust vents higher up.
A ridge vent runs along the roof's peak and allows warm attic air to escape. When properly paired with intake ventilation, it can provide ventilation without adding large, noticeable structures to the roof.
Soffit vents commonly serve as intake vents. They allow outside air to enter near the bottom of the attic.
Blocking these vents with insulation can interfere with airflow, which is why attic insulation and ventilation need to be considered together.
Not every house uses a ridge vent. Depending on its design, a Wisconsin home might have box vents, gable vents, turbine vents, or another ventilation setup.
Ventilation is especially important in a climate with large seasonal temperature changes. Excess attic moisture can contribute to condensation and other problems, while trapped heat can make the attic unnecessarily hot during summer.
Gutters may not technically sit on top of the roof, but they are closely connected to how the roofing system handles water. Gutters collect rain and melting snow as it reaches the eaves. Downspouts carry that water toward the ground, where it can be directed away from the house.
Problems can develop when gutters become clogged with leaves, pine needles, twigs, or other debris. Water may spill over the edge or back up against the roofline. Wisconsin homeowners also have to consider freezing conditions. Snowmelt that reaches cold gutters can freeze, and heavy ice can put additional strain on gutters and their attachment points.
Keeping gutters clear and checking for loose sections can help water leave the roof the way it should.
Roofing contractors use several words to describe the shape and layout of a roof. Knowing a few of them can make inspection results much easier to follow.
The ridge is the horizontal line at the highest point where two sloping roof sections meet.
A hip is an outward angle formed where two sloping roof sections meet. A hip roof has slopes extending down toward the walls on multiple sides.
The rake is the sloped edge of a roof along the end of a gable. It runs from the eave toward the ridge.
A gable is the triangular section of wall underneath two sloping sides of a roof.
A valley is the inward angle where two roof slopes meet. Unlike a hip, which directs water away from the intersection, a valley collects and channels runoff.
A Wisconsin roof has to deal with very different conditions throughout the year. Winter can bring snow, ice, freezing temperatures, and repeated freeze-thaw cycles. Spring and summer may bring heavy rain, wind, thunderstorms, and hail. Fall often adds leaves and other debris to gutters and roof valleys.
That does not mean every storm causes roof damage. It does mean small problems can become more noticeable when the weather puts the roofing system to work.
For example, loose flashing may not cause an obvious issue during light rain but could leak during a strong storm. Damaged shingles may allow moisture underneath during wind-driven rain. Poor attic ventilation can become more noticeable during periods of extreme temperatures.
Checking the roof periodically and after significant weather events can help catch trouble before interior damage appears.
You do not have to climb onto your roof to spot many warning signs. In fact, roof inspections are safer when left to someone with the proper equipment and experience.
Keep an eye out for:
Where a leak appears inside the house does not always tell you exactly where the roof is damaged. Water can enter in one location and travel along decking or framing before finally becoming visible.
Not necessarily.
A damaged component can sometimes be repaired without replacing the entire roofing system. A contractor might be able to replace several missing shingles, repair flashing, replace a section of damaged decking, or correct another isolated issue.
A full roof replacement becomes more likely when problems are widespread or the existing roof is already nearing the end of its useful life.
Factors that may influence the decision include:
Finding out which component is actually causing the problem is the first step toward deciding whether repair or replacement makes more sense.
Your roof is not one single layer. It is a collection of structural supports, waterproofing materials, shingles, flashing, vents, drainage components, and finishing pieces that have to work together.
Knowing the difference between a ridge and a valley or between decking and underlayment can make roof repairs feel a lot less confusing. More importantly, it can help you understand why a contractor recommends addressing a particular part of your roofing system.
Wisconsin weather gives roofs plenty to handle throughout the year, so catching damaged or worn components early can make a big difference.
If you have noticed missing shingles, leaks, storm damage, or other signs that something is wrong, contact FOREVER Exteriors to schedule a professional roof inspection. The team can check the condition of your roofing system, explain any problem areas, and help you decide whether repair or replacement is the right choice for your home.
