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What Goes Under Metal Roofing

Why These Layers Are Useful

Metal Roof Underlayment- Synthetic Felt paper vs. High temp Ice and water shield

You may be wondering why all these pieces of the roof are necessary. The most basic answer is protection. Without layers and underlayment, your home would feel colder, more damp, and, in the event the shingles got damaged, would be dripping with water almost immediately.

Underlayment is especially vital for several reasons:

Why You Should Use Roof Underlayment

While it’s not always considered necessary, underlayment is an incredibly important component to metal roofing system that has a major impact on its longevity.

A roofing underlayment will:

  • Protect against moisture penetrating through the roof, resulting in leaks.
  • Add extra insulation to your home to keep it from being drafty.
  • Absorb noise from rain or other elements on the roof.
  • Ensure that the roofing material laid on it looks uniform and even .
  • Keep your roofing warranty valid if applicable.

Self Adhering Membrane Underlayment

The complex sounding self adhering membrane underlayment is actually a lot more simple than it sounds, as it is in fact a kind of peel off and stick down style thats made up of a form of rubberized asphalt that is partnered with a polyethylene carrier sheet. Self adhering membrane underlayment works well to prevent ice dam build up in areas such as the eaves, but it can also provide protection for hotter environments which see temperatures of more than 230 degrees. To add to this, SAM underlayment is an efficient air barrier material as it fits completely flush with the surface of substrate. Always ensure you seek an experienced installations expert when utilizing self adhering membrane underlayment, as you may encounter peeling if you fail to attach the underlayment correctly.

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Choose The Right Materials

Two advantageous materials to have underneath a metal roof are underlayment and an ice and water shield. When it comes to the underlayment, there are a few different types to choose from. For metal roofs, stick to a good synthetic underlayment, but consult with your roofing manufacturer to ensure the underlayment is compatible with your roofing material. Furthermore, a non-granulated, premium ice and water shield may be required to place beneath metal roofing.

Do You Need An Ice And Water Shield Under Metal Roofing

Can I Install a Metal Roof Over Shingles?  Rare Manufacturing

If you live in an area that gets cold in the winter and sees plenty of precipitation throughout the year, then you probably should install an ice and water shield under your metal roof. For most roofing projects, two types of underlayment are needed, the first being an ice and water shield. This underlayment is made of either a rubberized-asphalt or butyl-based adhesive with a polyethylene carrier sheet, and it has an adhesive backing with a peel and stick feature. The product you choose should be able to withstand high temperatures and can be used with metal, tile, and other roofs with a scrim-reinforced top surface.

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The Best Metal Roof Underlayment Option

Costly metal roofs require a high-quality metal roof underlayment to provide thermal protection and waterproofing for your home. Selecting the best underlayment for a metal roof will significantly improve the homes health throughout its lifespan. It can also reduce the noise from rain. Underlayment also keeps the structures interior dry and provides a surface for contractors to walk on during construction.

Which Underlayment Should You Choose

You might have a good idea of which underlayment you should use after reading this blog. If so, thats great! The next step is to contact your local roofing experts to schedule a consultation, so you can tell them exactly what your wants and needs are, and they can suggest what they think will be the best type for you and your home.

At Legacy Service, we can be that local roofing contractor that answers all of your questions and completes your roofing installation or replacement project for you. Weve helped thousands of customers over the years, from New Hope, PA to Brick, NJ, and beyond! Were also a member of both the National Roofing Contractors Association and the National Association of the Remodeling Industry . Learn more about roof installation and replacement by calling us at 215-798-9790 or contacting us here.

Posted on Mar 5, 2020 in Roof

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A lot of elements play a role in maintaining the integrity of the roof, but as a homeowner, the most important components to pay attention to are the underlayment, ventilation, and material.

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Can You Put A Metal Roof Over Plywood

A metal roof should not be installed directly over bare plywood, but it can be installed over plywood once there are protective layers in between. A felt moisture barrier over the plywood is the bare minimum a slip sheet should also be installed to protect the felt sheet from potential damage from the metal roof.

The Rest Of Your Metal Roof Systems Roofing Materials

Does The Drip Edge Go Over Or Under The Roofing Underlayment? Metal Roof Underlayment At Eave Trim

Now you know the best underlayment for a metal roof, how its installed properly, and an idea of the cost. If you do get a new metal roof, be sure to ask the roofing contractor if theyll be using high heat and ice and water shield.

After reading this article, you know that underlayment is a crucial material for your metal roof system. However, there are even more crucial metal roofing components you need to learn about.

Thats why we wrote another article breaking down the 7 materials that make up your standing seam metal roof system.

Since 1990, the team at Bill Ragan Roofing has proudly helped homeowners in the Nashville area with all of their metal roofing needs. You can count on our metal roofing installation expertise to give you a new metal roof thatll last for decades.

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First Two Underlayment Layers

On most projects, there are two types of underlayments needed. The first on the list would be the ice and water shield. This is a roof membrane underlayment made up of either a rubberized-asphalt or butyl-based adhesive with a polyethylene carrier sheet. It has an adhesive backing with a peel and stick feature. This membrane should be labeled high temperature to withstand the surface temperature of the roof on a hot summer day. The heat in hot areas of the country, even here in New England, can exceed the melting point of some of these products. The product should be a premium, high temperature ice and water shield for use with tile, metal, and other roofs with scrim reinforced top surface. It self-seals around nails and provides protection for roof areas prone to ice and water intrusion.

The product needs to be installed on the eave edges up the roof at least two feet inside the face of any exterior wall. The rakes on gable roofs also need treatment to the same standard. All valleys and hips need to be covered. Penetrations such as chimneys, skylights, solar tubes, and vent pipes need to be surrounded with ice and water shield, as well.

If the roof slope is below 3/12 pitch , the entire roof should be covered, but only if the roof is conventionally vented .

How To Install Synthetic Roof Underlayment For A Metal Roof

1. Install the Drip Edge

Your first step is to apply a drip edge to the eave and cut drip edge flashings at the corners, pressing them lightly on the eave end. Now lightly hammer in a nail at the end, and always align the material using the chalk line.

2. Overlap and Cut Drip EdgesMake sure you overlap meeting drip edges by 2 inches and when they meet in a valet, cut the overlapping tabs and press these tabs firmly to form a seamless, clean corner.

3. Align the FeltRoll out around 12 feet of material using the chalk line as a guide. Make sure there are no creases or bubbles. Reroll and unroll to make sure of this. While unrolling, peel off the paper backing.

Try installing the bottom half first on steeply angled roofs. You can also apply the underlayment at the same time as the felt . After this, install the shingles. Add more felt when you are 6 inches away from the top edge.

Valley Application

You must always apply for extra protection at the valley. You do this by rolling out the material and driving nails on one side to temporarily hold it in place.

Now fold over the other side while peeling off the paper backing and press into place. After this, remove the nails and peel off the paper from the other side.

Maintaining Parallelism

When overlapping, add at least 4 inches and use the chalk line as a guide. Using the lines as guides will make sure that all applications are parallel, all while reducing bubbling, creasing, and ugly roofing work.

Apply the Underlayment

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Three: Install Flashing And Gutters

Use the tape measure to determine the length of the roofs edge. Cut the flashing material to size using the metal snips and install along the roofs edge with ½ roofing nails.

If you need to install gutters in any of the valleys, cut the gutters to size using the snips. Then secure the gutters in place with the ½ roofing nails.

How To Install Metal Roofing To Plywood

sheathing: " The contractor has installed new osb over the existing ...

Installing metal roofing over plywood is less time-intensive and more affordable than a shingle roof, but there are still several steps you should take when installing a metal roof to plywood to ensure that your roof does not leak and will stand the test of time.

Follow these steps when installing metal roofing on top of plywood:

  • Inspect the existing roof. If the plywood on your roof has not been recently installed, there could be rotten or warped plywood. You must first check for soft spots and warped wood.
  • Repair existing damage. If you discover wood rot or warping, replace the damaged sheets of plywood. This can be labor-intensive, and you may be tempted to cover those areas, but you will be dramatically reducing the life of your metal roofing if you do. Remove the damaged sheets and replace them with new plywood.
  • Replacing rotten wood is critical because dry rot will spread. Adjacent areas of healthy plywood may eventually become rotten, and then the screws you have placed there will not hold. Warped wood should also be replaced. Warping signifies that the wood is prone to rot and will prevent you from laying the metal roofing flat. Wind will be able to get underneath the roofing and pull it off your roof.

    Be sure to use plywood that is thick enough. The plywood or OSB you use for a base underneath your metal roofing should be at least 7/16 inch thick. This thickness will ensure that the wood is sturdy enough to hold the screws in place and support the metal roofing. .

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    Ner With The Right Roofing Provider Skywalker Roofing

    At Skywalker Roofing, we pride ourselves on installing roof systems of superior quality with superior workmanship. Theres a reason we often say that a Skywalker roof is the last roof youll ever need! We have all the materials, tools, training, and expertise needed to craft and install your custom standing seam metal roof right onsite. In addition, we believe in creating the best possible support system for your roof, which is why we offer a Total Protection Roofing System from Owens Corning which features Titanium Synthetic Underlayment. In fact, Titanium Synthetic is really an ideal choice for both asphalt shingles and metal roofs alike.

    While selecting the right roofing materials is certainly an important decision, choosing a local roofing contractor you can trust is even more important. We offer premium quality metal roofing in your location. Get an A-grade roofing service for all types of projects. If youre looking for the right roofing provider in NC or VA, then look no further than Skywalker! Were proud to serve the NC Piedmont Triad, Piedmont Triangle, Charlotte Metro/Lake Norman areas, and southern VA region . In addition, our happy customers give us an average rating of 4.9 stars on review platforms including Google, Facebook, BBB, Guild Quality, Shopper Approved, and Angies List!

    Ready For Your New Metal Roof

    Metal roofs are the perfect way to make sure that your roof looks amazing, lasts forever, and protects your home from whatever the weather can throw at it. Beartooth Metal Roofing serves the areas within a few hundred miles of Billings, Montana. So if you live in Cody, WY, we can put a metal roof on your home. If you have a cabin near Cooke City, Montana, we can get a metal roof on your cabin. If you have a luxury mansion along the Stillwater River near Absarokee, MT, we can make it look perfect.

    You get the idea. Give us a call at to schedule a time for your new metal roof.

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    Metal Roofing Can Work On Roofs With Low Slopes

    It’s often believed that metal roofing is suitable only for roofs with a steep slope, but standing-seam metal roofing can work fine on gently pitched roofs. This type of roofing is installed in large sheets with seams that are raised and sealed tightly together to resist water. While some slope is necessary to ensure water run-off, most homes can accept metal roofing.

    Remove Old Roofing And Repair Any Damage

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    While it is possible to install a metal roof over old asphalt shingles, a full tear-off of the old roof is highly recommended. Removing the old roof will allow you to inspect the sheathing and flashing and replace any problem areas before moving forward. That way, the sheathing and flashing can be inspected before the new roof goes down, reducing the chance of a leak.

    • Start from the top of the roof and remove the old shingles along with the flashing, underlayment and vents.
    • Hammer down or pull any large nails that are exposed by the removal.
    • Inspect the underlying roof sheathing for damage and make any needed repairs with sealants and roofing adhesive.
    • Install a layer of roofing underlayment, including a layer of felt paper or rosin slipsheet, as recommended by the roofing manufacturer. Metal panels expand and contract at different rates than the sheathing, so its important to follow manufacturers guidelines regarding underlayment.

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    What Does Roof Underlayment Do

    Roof underlayment adds a protective barrier that acts as a defense system. It is crafted to stay and lay under the metal roof.

    It also serves as an extra layer to help protect from water, heat, cold, and other weather elements. That means it helps you with energy efficiency.

    Underlayment also helps as a sound barrier for your metal roof.

    As the go-to metal roofing contractor in the Pacific Northwest, Mountaintop Metal Roofing can help you make heads or tails of roofing materials. If youre considering asphalt shingles for your roof deck, consider metal roof shingles or panels, instead.

    One of the most popular roofing projects in the United States is the installation of standing seam metal roofs. It withstands high temperatures all temperatures, actually! and, like all metal roofs, acts as the ultimate water shield.

    What are the most popular types of roof underlayment for metal roofing systems? Lets take a closer look at these roofing materials.

    Metal Roofing Can Be More Cost

    Although most metal roofing products carry warranties comparable to the very best asphalt shingles , in practice, metal roofs have been known to last 50 years or more. According to State Farm Insurance statistics, metal roofs routinely have a longevity of 40 to 70 years. It is therefore very rare for a homeowner to install more than one metal roof over the time he or she lives in the home. By contrast, a homeowner will likely replace an asphalt shingle roof two or even three or four times over a 50-year period. Overall, while the cost of a metal roof is more expensive than asphalt roofing , it can save money over a long period.

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    Final Thoughts On Synthetic Vs Felt Underlayment

    So, is synthetic or felt paper underlayment the best choice for you?

    Well, it depends.

    For help deciding between these two options, ask yourself these questions:

    • How long do I want the roof underlayment to last? How about the actual roof?
    • Does my/my customers budget allow for an expensive underlayment?
    • Will my/my customers underlayment be exposed to long periods of sun or heat?
    • Do I want to be able to buy my underlayment at a big-box store?
    • How concerned am I about fire resistance or having a Class-A fire rating?

    At Sheffield Metals, we understand how important it is for you to choose the right underlayment right from the start, which is why recommend and offer synthetic underlayment options from Sharkskin, a trusted supplier providing value and long-term underlayment solutions.

    Taking Care Of Your Building Envelope

    Our all

    The roof is an important element of the Building Envelope. A Building Envelope is the physical separator between the conditioned and unconditioned environment of a building including the resistance to air, water, heat, light, and noise transfer. It needs to be addressed with the utmost care and consideration. Be sure that the contractor you choose is trained in the best methods of installation. Having the Right Stuff and not having the skill to do the installation nullifies the benefits of its use.

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    Metal Roofing With No Decking Or Underlayment

    Is it generally permissible to construct a SFR dwellings roof with no sheathing? I have seen it done this way on plenty of storage sheds and metal buildings. And I have seen plenty of metal roof coverings on SFR homes but they have mostly been re-roofs over existing roofs with plywood decking, or new roofs with plywood decking. This particular roof has very lightweight metal covering. The gable endwall has plywood sheathing and vinyl cla

    Solid sheathing is only required for shingles. From there, you will have to follow manufacturer guidelines. In my opinion, looks like a fine install from here in GA.

    I bet its gonna get real noisy in a hail storm!

    I bet its gonna get real noisy in a hail storm.!

    not to mention the potential for sweating/condensation.

    Shouldnt your metal roof have underlayment installed, per IBC 1507.4 ? And how about flashing, such as drip edge? I do not think this roof meets residential roof standards.

    Like Larry said, that roof is going to have a big condensation problem, Ive seen it.I would let the buyer know that this roof is not built right, and is likely to have problems that would have been prevented with proper construction.

    Material and procedures that are meant for equipment or storage sheds were never right for a home when it comes to metal. Plywood sheathing has a purpose.

    That is what I see Brian. Underlayments are required for that type of roof covering, which is metal. Hard to do if you dont have a roof sheathing.


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