Choosing the best roofing components for your shingle roof

AlexRoofing

shingle roof components

Choosing The Best Roofing Components For Your Shingle Roof

One question that we often come across on our initial assessment of the roof with potential customers is what type of roof components are going to be installed on their roof. There are many homeowners that believe that all roofing contractors pretty much use the same roofing materials across the board. That assumption is however, far from the truth. Not all roofing materials are created equal, and we are going to give you an in depth explanation of what is out there on the market today and what you should expect to be installed onto your roof.

It is always important to understand not only how each roofing component will be installed but the quality of the roofing component itself. We have broken down seven of the main components of the roof below and explain how each of them play a crucial role in the roofing system itself. Overlooking these components can significantly shorten the lifespan of your roofing system, in some cases by more than half!

The Roof Structure

The roof structure is a critical part of the roofing system. the roof pitch, amount of facets, age of the structure and quality of the original frame installation are all factors that will determine the right type of roofing component that is needed to be installed. Ignoring this can cause leaks and premature aging of the roofing system. It is always advisable that the roofing contractor do a thorough inspection of the attic in order to see what shape the framing as well as the roof decking is in. Although it is difficult at times to spot all of the rot and soft spots on the decking from the underside, it can give you an accurate picture of the overall health of the attic as well as problematic areas to focus on fixing during the roof installation.

Inspecting the attic can also help to get a good grasp on how well the empty attic space is breathing and if there is proper airflow throughout the open attic cavity. Not having enough ventilation and airflow can lead to moisture buildup and mold formation. Part of the inspection should include checking to see if there is air coming in from the soffit areas and wether or not the insulation may be blocking the airflow.

Roof Trusses

Roof trusses should always be inspected in the attic to see if the frame has been compromised in any way. If there has been extensive leaking over a long period of time, it may be necessary to sister or re-support some portions of the trusses to ensure that the structural integrity of the frame is sound. Defective materials during the initial installation of the home may also lead to sagging trusses or cracks in the wood itself. It is always a good idea to double check any porches and overhangs to ensure that they are not sagging or damaged in any way as well. The ASHI Reporter website has a great resource along with pictures to show you exactly what you should be looking for when inspecting roof trusses.

Roof Decking (Plywood or Sheathing)

If there is rotten or damaged plywood on the roof, it needs to be changed out prior to the roof shingles being replaced. If your trusses are spaced 24” apart, ask the contractor if they are planning to use H-Clips. Not installing them can lead to warping at the seams of the plywood. They often times fall off when the plywood is being changed out and many roofing contractors do not bother putting new ones back on.

There are two different types of plywood, OSB(Oriented strand board), or CDX. Oriented strand board is just that, random strands of wood pressed together to make the plywood. CDX however, is different layers of wood veneer glued together to make a sheet of plywood. The letters CDX refer to the grading of the wood veneer. CDX plywood has “C” grade wood veneer on one side and “D” grade on the other side. Both OSB as well as CDX plywood comes in different thicknesses. It is important to know which type is required for your roof. Typically 1/2” plywood works for 16” trusses while a thicker plywood is required for 24” trusses. If you are simply replacing the roof shingles and a few sheets of plywood need to be changed out, the rule of thumb is to match the thickness and type of plywood that is currently on the roof. Sometimes, CDX plywood as thin as 3/8” is installed on a roofs. If the attic is not ventilated properly and the plywood is thin, the plywood gets “baked” from the inside and the glue separates the layers or “delaminates”. Delaminating and dry rotting of roof decking often occurs when there is inadequate air ventilation in the attic cavity, especially if the plywood is 3/8” thick.

Roofing Underlayment

When it comes to roofing underlayment, there are a variety of options available on the market that vary in quality as well as function. Depending on the township that you live in, usually 3 ft of ice and water shield is required on all lower eaves. If a roofing contractor is trying to save money, they will typically stick to the bare minimum required for the ice and water membrane. Keep in mind that there are many different ice and water membranes on the market in varying quality. Home Evolution typically installs a minimum of 6ft of ice and water membrane on the lower eves, as well as in valleys, side walls, around chimneys, skylights, vents and pipe boots. When it comes to everything above the ice and water membrane, there are mainly three types of underlayment to choose from.

Felt Paper

The one benefit to 15lb and 30lb felt paper is the fact that it is cheap. On the installation side of the equation, it is heavier than synthetic underlayment, more labor intensive to install, easily rips during installation and degrades quicker over time. If price is a deciding factor, felt paper is the way to go. Otherwise, there are much better alternatives on the market.

Synthetic Underlayment

Synthetic underlayment outshines felt paper in multiple areas. Although it is lighter than felt paper, it is far superior in durability. It is also easier to install and safer to work on. Since it is fabricated out of synthetic materials, it also degrades much slower than felt paper. The only drawback to synthetic underlayment is the fact that it is more expensive than felt paper and the fact that it is not breathable. This can be a problem on roofs that do not have an adequate amount of airflow, especially where vaulted ceilings are involved.

Breathable Synthetic Underlayment

Breathable synthetic combines all of the components of the synthetic underlayment with one additional component, the ability to allow the material to breath. This allows moisture to escape from under the roof. This way, the decking is less prone to warp and rot since moisture is not being trapped underneath the surface. The one drawback to the breathable synthetic is the fact that is much more expensive than felt paper and synthetic underlayment. Most roofers will not even offer breathable synthetic simply because it cuts into their profit margins. However, it is well worth the investment if you are looking to maximize the lifespan of your new roof.

Chimney Flashing and Components

The chimney is one important component on the roof that always needs to be inspected before you plan to replace the roof. There are three main components of the chimney itself that should be examined before you proceed with the roof replacement.

Top of the Chimney (Chimney Crown)

The top of the chimney will always have an opening where a flue comes out or a pipe. If there is a chimney cap of any kind or a chimney chase, it is always a good idea to inspect for failing components. Depending on the makeup of the cap and chase, it may be that it has rusted through, components have broken off, or it has simply come loose. If the crown of the chimney does not have a chimney chase but rather is made up of mortar, check for possible cracks and deterioration. Although most roofers are able to swap out most chimney chases and chimney caps. We have a supplier in Albany that we work with that custom fabricates stainless steel chases for us so that it fits perfectly on your chimney, no matter the size. When it comes to a mortar or cement crown, not all roofing contractors will be able to re-mortar the chimney crown. In this case, you may need to call in a brick mason to complete the job for you.

Mortar Joints

If the mortar joints on the brick or cinder block are deteriorated, cracking, or chunks missing, it is always a good idea to take care of this. Avoiding it can lead to leaks on the interior of your home, even with a newly installed roof and chimney flashing. Typically it is best to have the brick mason fix the mortar joints and chimney crown prior to the roof install as mortar tends to stain the surface of the shingles.

Chimney Flashing

If the chimney flashing needs to be replaced after inspecting the roof, it is important to make sure that the roofer you hire to do the roof replacement knows how to properly refresh the chimney. There are different ways to go about this. The correct way of doing it involves ice and water membrane, step flashing and counter flashing. Some roofers tend to caulk the counter flashing to the chimney itself, while others will actually grind in the counter flashing into the chimney. The latter method is typically the better method as caulking and tar tends to pull away from the chimney and crack as it expands and contracts with the changing seasons.

Roof Shingles

Most shingle manufacturers incorporate the same 3 raw material components into the fabrication of shingles; fiberglass, asphalt and granules. The amount of raw material that goes into the shingles as well as how they are put together will determine the overall quality and longevity of the shingle itself. Every roof manufacturer tries to put their own spin on the shingle to try do give it a perceived “advantage” over the competitors shingle.

It is important to do your research when choosing the right shingles to be installed onto your roof. Each major roofing manufacturer will always boast having the “best shingle on the market” so it is up to you to decide which shingle best fits your roof. Things to consider are the specialty components that may truly give the shingle an advantage such as a components that increase the wind resistance rating, the manufacturers warranty that comes with the installation, as well as feedback from other customers that have used the product on their roofs.

Typically, 3 tab shingles will have the shortest lifespan on your roof, while architectural, or laminated shingles will last much longer. One thing to remember is that there are many different grades of architectural shingles on the market. You ideally want a Class A rated shingles. If you are looking for a step up from the architectural shingles, there are designer shingles that typically mimic, tile, shake or slate roofs. The designer shingles typically will come in at a higher end price point.

Is adding a second layer of shingles a good idea?

Adding a second layer of shingles to an existing shingled roof is never a good idea for several reasons. Keep in mind that most municipalities will not allow more than two layers to be installed on a residential roof. Here are some other reasons why more than one shingle layer is a bad idea below.

1. Any kind of manufacturers warranty is automatically voided.
2. You do not have the ability to replace any rotted or failing roof decking.
3.You have a lot more weight for your roof trusses to support, for a long period of time.
4.Adding the second layer will shorten the lifespan of the newly installed roof.
5.The second layer can trap heat, causing both roofing layers to decompose much sooner than they would as a single layer.
6.It is aesthetically unappealing since you are not installing the new shingles on a smooth flat surface and will see random bumps, lifting, curling, etc.
7.If you are planning to sell the home in the future, this can negatively affect the sale.

Ridge Vents and Roof Vents

Proper air ventilation in the attic is crucial in order to maximize the lifespan of your new roof. Air circulation helps to draw hot air and moisture out of the attic, preventing mold from growing and the decking from delaminating or dry rotting. The roof manufacturers warranty will typically only cover the ridge vent if it is a part of their roofing package and their own ridge vent is installed. Choosing the cheaper ridge vents or box vents can lead to premature leaks. Our recommendation is to always go with a premium vinyl ridge vent system at the peak for maximum airflow and long lasting protection. We have listed the standard types of ridge vents available on the market today with the pros and cons each comes with.

Aluminum Ridge Vents

Although inexpensive, these typically come in 10 ft sections. They tend to leak at the overlapped sections as well as on the surface where the nails are exposed. These tend to fail around the 15 year mark.

Mesh Roll Ridge Vents

These ridge vents are typically rolled out onto the roof peak and nailed down. The caps are then nailed over them. Although they are a step up from the aluminum ridge vent in the sense that they stop the leaking problem, they come with a hidden problem of their own. Since they are nailed down, typically with the same nails that are used on the shingles. they get compressed. This limits the actual amount of air that can escape through the ridge vent itself. The other downside to these is the fact that dust and debris from rising air in the attic will clog them from the inside, leading to ventilation problems and a much higher chance of mold developing inside of the attic itself.

Vinyl Ridge Vent

This ridge vent is a durable ridge vent that combines the maximum airflow of the aluminum ridge vent with the seamless, hidden nail mesh rolled ridge system. It typically sits at least 3/4” above the shingles and has no exposed nails across the peak so that none of the nails corrode and pop up. The only downside is the fact that it comes with a higher price point than the two previous ridge vent systems.
Different types of ridge vent systems

Pipe Boots

Although your shingles may last for 25-30 years, cheap accessory products that may be installed along with the new roof such as the pipe boots will cause leaks. For example, the standard pipe boot that is installed by roofing contractors in the Albany, NY area will start to crack and fail as early as the 12-15 year mark. It is important to ask the roofer not only what type of a pipe boot will be installed on your roof but how they are planning to install it as well. It is crucial, especially in colder climates to install an ice and water membrane around the pipe boot flange as well as apply a sealant around the pipe boot itself as well as any exposed nails.

Skylights

When it comes to the installation of skylights, it is always a good idea to have someone that is experienced specifically in the installation of skylights install them. Most skylights come with two components, the skylight itself along with the flashing kit. Flashing them out properly with the right waterproofing membrane and the flashing kit is crucial, especially in low pitch areas. Anything that is above a 3/12 pitch can be deck mounted, or directly on the roof, while anything under a 3/12 pitch should be curb mounted (sitting on a built up frame). Most skylights nowadays are manufactured by Velux. If you are not sure who to hire to install your skylights, you can search for a Velux certified skylight installer directly from the Velux website here.

As you can see, there are many components that go into a roof installation. Knowing which components are the best fit for your roof will allow you to make an educated decision when hiring a roofing contractor to take on the roof replacement on your home.