Top 7 Best Underlayment for Metal Roof Reviews in 2021

Buildings are meant to last for a very long time and therefore, particular attention must be paid at the construction stage so that there is a minimum need for repairing before the time arrives.

The roof is a part of any construction that should be given careful consideration. After all, it’s the roof that protects us and our home from the elements and we don’t want it to literally fall on our head as a result of lack of attention and time.

For metal roofs and other types too, an underlayment acts as a barrier against rain, ice, heat, and cold. In fact, it protects the metal roofing material as well, making sure it runs through its expected time.

As there are two types of underlayment to choose from, you should know the differences to make an informed choice. To help you choose the best underlayment for metal roof, this article has been put together after much research on products and user reviews. Read on to know the key points!

Is Underlayment Necessary For Metal Roof?

Many people don’t believe that underlayment is necessary for the metal roof because it’s already a sturdy material that comes in large-sized sheets and gives sufficient protection to the house. Although this could be alright in the short-term, the long-term effects are damaging.

The underlayment for metal roof serves several purposes.

1. Waterproofing Features:

Let’s look at what metal roofing does – it has waterproof features to prevent water from seeping through the roof into the house.

So, it makes sense to have an underlayment for metal roof so that there are proper insulation and an extra buffer to prevent rain and moisture from settling on the bare metal roof, and harming it in the long run.

2. Great Heat Conductor:

It is also a good conductor of heat, meaning that a metal roof becomes cold in winter and very hot in summer.

3. Minimizing Sound:

Metal roofing can produce very loud noises when there’s rain falling on it or if some animal walks on it. To minimize disturbance from such sounds, an underlayment for a metal roof is a good idea.

However, there are cases where you don’t need an underlayment. For example, if you are putting a metal roof on asphalt shingles, then an underlayment can be done without. Another case is where your patio has an open beam design which negates the need for an underlayment.

Top 7 Best Underlayment For Metal Roof Reviews In 2021

1. ArmorLay 25 Synthetic Roof Underlayment 4' x 250'

The synthetic component of this metal roof underlayment makes it tougher than its felt counterpart.

Each roll of this product covers 1,000 square feet of surface area and the whole thing weighs less than 25 pounds, making it lightweight and easier to transport.

When compared to traditional felt paper, a single roll is 5 times lighter, 5 times stronger, and gives 5 times more coverage. In addition, the results are longer lasting and it produces a wrinkle-free finish. It’s better suited for regions with very high temperatures as it has a higher tolerance for sizzling temperatures.

It can withstand direct exposure to ultraviolet rays from the sun for 60 days without drying up. This feature helps in hot and dry climates and in situations where construction has been put on hold temporarily.

Besides being waterproof, the lower surface has anti-slip polymer applied so that it can be used easily and safely. The material is also uniquely textured so that walking on sloping roofs become a cakewalk.

The product is suitable for use with steep slopes, metal roofs, and asphalt shingles. It’s free from buckles or warps, thereby giving a smooth look. With its cool gray color, it retains less heat and doesn’t get very hot to the touch, making the contractors’ work easier.

This does not tear easily and is more durable, thanks to the stronger thermoplastic material. Also, there is no chance of this flying off the roof or shifting from its place in case there is a gale.

Highlighted Features:

  • One roll weighs less than 25 pounds for easy transportation.
  • 5 times stronger and lighter than felt paper.
  • One roll covers 1,000 square feet area.
  • Wrinkle-free for a smooth finish.
  • UV exposure for up to 60 days. 

2. Tyvek Protec 120 Roof Underlayment 4' x 250' - 1 Roll

When you have to rely only on yourself to do the roofing, this product will act as a second pair of hands to make your job light!

Not only can you use this for new roofing but also for re-roofing and repair work on the roof. It’s compatibles with the most common roofing materials – metal, cedar shingles, and asphalt shingles.

The walkability feature of this metal roof underlayment is industry-leading. Coming from the renowned house of Dupont, it’s not a surprise! It has a unique 4-layer construction that makes its walkability feature incomparable.

The anti-slip layer makes it easy to get a firm grip on the roof and results in high performance. Its strength is commendable; the credit goes to the woven polypropylene.

A layer of water barrier makes it completely waterproof. The icing is the grooves on the top layer to resist against dust and water to settle.

The product is perfect to ensure a safe working environment and its suitable for 2:12 or even higher slopes.

Some users have claimed that the slight static on it plus its lightweight feature makes it easier to have it properly secured to a plywood roof deck, making the installation job the work of a single pair of hands. Even high winds cannot move this from its place.

As each roll of the product is 4 feet tall, it fosters a quicker dry-in time than conventional 3-feet felt ones. The wrinkle-free finish makes chalking an easy process. The UV exposure duration is 3 months.

Highlighted Features:

  • Unique 4-layer construction for top performance, strength, and protection.
  • UV exposure longer with 3 months for greater moisture and dust barrier.
  • Lightweight for single-user installation.
  • Quicker dry-in time with a 4-feet tall roll.
  • Superior walkability for a safer work environment. 

3. Roof Protector Underlayment Roll - 42" x 286'

Suitable for both residential and commercial complexes, this roof protector has all the features for a hassle-free installation.

The lightweight material makes installation easy under roofs made from metal or asphalt shingles. With a high strength to weight ratio, you can use this on sloping roofs with 2:12 or higher ratios.

Each roll covers 1,000 square feet and with 10 squares per roll and 2-inch chalk marks, installation is flat and easy. The design is such that it remains uniform after installation. Moreover, the squares make laying more efficient as you will need less labor and time and fewer overlaps and fasteners.

With a special 4-layer construction, you will get any benefits from this roof underlayment. Its strength prevents tearing at fastening points - thanks to the woven polypropylene scrim – making it highly durable.

It’s also highly resistant to slipping with its firm grip layer on top. This is such an important feature for contractors who work on sloping roofs in dusty and wet conditions. This property ensures top safety and minimum occupational hazard.

The lamination layer provides superb protection against moisture and rain so that your roofing will not be in ruins. Even 90-days continuous ultraviolet ray exposure from direct sunlight will not affect the roof protector and won’t dry it up.

With superior insulation property, you can use this with peace of mind even in climates with extreme heat and dry conditions. The medium gray color helps to resist heat so that you won’t find it hot to the touch plus with less heat retention, the roof will not absorb and transmit the heat throughout the home.

Highlighted Features:

  • 1,000 square feet coverage per roll with 10 squares for easy installation.
  • Flat design for a uniform finish.
  • 4-layer construction for moisture protection, anti-slip grip, and strength.
  • UV exposure duration of 90 days.
  • Superior insulation property for use in extreme weather conditions. 

4. Tyvek Protec 200 Roof Underlayment Roll - 4' x 50' - 2 Square

If you have found it difficult to seal steel roof underlayment around nail holes, then this product is for you as it has superior self-sealing abilities.

Whether the roof is made from slate, steel, asphalt shingles, tile, or cedar shingles, this roof protector is for all types of materials.

With a UV exposure of up to 6 months, you get the maximum scope to have the roof material protected under situations where the construction has to stop for a prolonged period. No dust or water will penetrate the synthetic material to seep into the roof and damage it.

The 4-feet by 50-feet roll covers 2 squares, making it ideal to work on small-scale projects, or if you’re working by yourself, or in situations where you need only a few squares.

The walkability feature is one of the top in the industry and you can work comfortably work on 2:12 or even higher slopes, making it the best underlayment for metal roof.

Create a safe work environment with this metal roof underlayment with its leading-edge 4-layer construction. The slip-resistant layer on top means you can get a firm grip while working on the roof, thereby ensuring high performance.

The anti-tear property makes this a durable product as it is composed of woven polypropylene. The grooves on the top layer prevent the accumulation of dust and water and provide an intelligent water barrier. Hence, you get an all-around safe and effective construction environment.

The material is free from wrinkles and gives a smooth and flat finish. It’s also easy to put chalk marks on for ease of work.

Highlighted Features:

  • UV exposure for up to 6 months.
  • 4-layer construction for strength, performance, water barrier, and safety.
  • Anti-tear property for durability.
  • Easy to chalk and free from wrinkles for a uniform look.
  • 2 squares coverage for smaller or single-handed projects.

5. Tyvek Protec 120 Roof Underlayment - 4' x 50' - 2 Square

Wondering how to put the roof underlayment on that patio all by yourself? Worry no more as this metal roof underlayment will make your work light but performance heavy!

The 4-feet- by 50-feet package with 2-square roll size is easy to handle for projects where you are the sole worker, or you need just a few more squares, or if the project is a small-scale one.

Use it on slopes with 2:12 or higher strength to weight ratios with its excellent walkability. Be it metal cladding or cedar or asphalt shingles, this underlayment for roofs is the perfect protector.

With the signature 4-layer construction, you will have no complaints regarding the strength and durability of this product. The top layer is specially designed with grooves to prevent the collection of dirt and water.

The anti-slip covering makes walking on it safe and comfortable. The woven polypropylene composite creates strength and anti-tear abilities. With the water barrier property, you can be sure that your roofing material will remain safe from the elements.

Its UV exposure is up to 3 months, making it a worry-free product if you need to halt the construction temporarily before putting the roof on. It’s the ideal metal roofing underlayment for commercial and residential buildings as it can withstand demanding weather conditions.

It’s easy to lay it flat and remains so, giving a warp-free and uniform finish. If you want to put chalk marks on the material, you can do so easily.

Highlighted Features:

  • 4-feet by 50-feet with 2 squares for easy handling.
  • Excellent walkability feature for 2:12 or higher slopes.
  • Suitable for all types of roofing materials – metal, cedar, or asphalt.
  • UV exposure of 3 months without drying.
  • Warp-free and smooth finish, easy to chalk. 

6. Roof Underlayment 48inx250ft

Why would you choose felt paper for a metal roof underlayment when you can have this product that’s 14 times stronger and 11 times lighter!

The advanced resin technology and the SURE-FOOT patented design have been combined to give you superior walkability. The product has a unique nodular walking surface that guarantees your foot won’t slip on the slopes of a roof while you are working on it.  

On top, the 6 months’ UV exposure comes handy when you have to shelve your construction project for a while. No worries as when you do return eventually, you will find the roof underlayment still in its pristine condition, with no harm done to the roofing material.

Compatible with asphalt, metal, synthetic, and cedar shingles, this protector is the go-to solution when you’re in doubt. Its construction is such that it won’t allow the growth and spread of mold.

The surface is a cool gray color, ensuring that heat is neither retained or distributed throughout the roof and warming up your home or office. Be it -40 degrees or 240 degrees Fahrenheit, the underlayment will work equally efficiently to protect your roof under all types of extreme weather conditions.

A Class 4 hail rating further attests to the strength of this steel roof underlayment, making it not only lighter but much more durable than felt roof underlayment. Each roll comes in a dimension of 48 inches by 250 feet.

It’s easy to lay flat on the surface and will produce a smooth and neat finish.

Highlighted Features:

  • SURE-FOOT patented design and resin technology for superior walkability.
  • 14 times stronger and 11 times lighter than felt.
  • 6 months’ UV exposure for more flexibility.
  • It withstands temperatures from -40 to 240 degrees Fahrenheit.
  • Class 4 hail rating that indicates more strength

7. Interwrap Corp Titanium Udl 50 Com-Grade Roof Underlayment

Had an unpleasant experience with felt roofing underlayment in the past? Unlike felt, this titanium-infused synthetic roof underlayment will not degrade, dry out, or break down.

This product is ideal for conditions where you expect heavier foot traffic and more exposure time. That’s because the composition is thicker and more robust. It’s suitable for a wide variety of roof materials including concrete and clay tiles, metal, slate, and heavier asphalt shingles with lamination.

The self-adhesive property of this metal roofing underlayment makes it a convenient way of laying and securing it in place. The unique gray shade is a result of the combination of advanced polymers, making it resistant to heat and at the same time, much more durable than felt paper.

With a 6-month UV exposure period and the cool gray color, the environment on the roof provides a cooler working environment. The patented SURE-FOOT slip-resistant technology makes the environment also safe as the contractors are sure to have smoother walkability on sloping roofs, during rains as well.

Accelerate the efficiency of your work by having fewer overlaps and cuts as well as more comfortable handling with the lightweight package. Each roll comes in a 48-inch width and 250-feet length. The results: less labor and time and fewer rolls.

Besides laying flat, the underlayment for metal roofing also resists mold formation and is waterproof as it’s 100% synthetic. Even in cold climates, it retains its shape and does not crack or become stiff. Anti-tearing property also contributes to the longevity of the product.

Highlighted Features:

  • 100% synthetic with titanium to prevent drying out breaking down.
  • Thicker composition for heavier foot-traffic and higher exposure projects.
  • Self-adhesive property for easier installation.
  • 6 months’ UV exposure duration.
  • SURE-FOOT patented technology for better slope walkability. 

How to Choose The Best Underlayment For Metal Roof?

Since underlayment for metal roof is a considerable investment, you should weigh the key factors before deciding to buy it. The following will give you a low-down on the topic.

A) Synthetic Versus Felt Paper

Synthetic underlayment for roofs is made from a combination of polymer and polypropylene or polythene. This has several advantages over the felt type.


It’s more durable, lasting for almost 40 years. It can withstand longer periods of exposure to the sun and ultraviolet rays, sometimes as much as up to a year. Because of the material, the synthetic underlayment is naturally less prone to tearing. Moreover, they do not shift or move while the roof construction is ongoing.

High Temperature and Heat Retention

The underlayment for metal roof should be able to withstand very high temperatures and the synthetic type is better equipped to do this. The grey color of synthetic steel roof underlayment retains less heat due to the color and also becomes less hot to the touch, providing comfort to the contractors.

Therefore, you should consider the building location and the climate there before considering buying an underlayment for metal roof.

Economical And Lightweight

Synthetic type makes the best underlayment for metal roof as it gives you more bang for the buck. Although the price point is 2-5 times more than that of felt, they reduce overall expenditure.

How? First of all, they last longer than their felt counterparts, giving you value for the money spent. They come in larger size rolls that give more coverage per square foot. Felt rolls come in rolls of 2 to 4 squares, thus requiring many rolls to finish a roof.

Felt paper weighs anywhere between 15 and 30 pounds per square, whereas the synthetic ones weigh only 2 to 4 pounds, thereby being less weighty on the building construction and more comfortable for workers to work with.


With the slip-resistant surface of synthetic metal roofing underlayment, workers have a safer work environment as they can walk the slopes easily, knowing that they have a firm grip on the surface. Hence, attention should be paid to the roof slope and its geometrical shape before investing.

Recyclability, Smooth Finish, Fire-Resistant

Recycling of synthetic materials is also easier than felt ones. Any scraps of leftover materials can be disposed of correctly without harming the environment. Other advantages of synthetic underlayment for metal roof includes a wrinkle-free finish and higher resistance to fires.

The Flip Side

The flip side of these synthetic underlayment includes low permeability and the need for stick and peel ones only for low slopes.

Low permeability means that due to the synthetic nature of the roofing underlayment, the moisture from inside the building cannot escape outside. Hence, proper ventilation and attic system must be in place before installing a synthetic underlayment for steel roof.

B) Surface

A smooth, non-granulated surface of the underlayment should be considered. This will not damage the underside of the metal roofing material by scratching it.

C) Size Of Project

Depending on the size of the construction project, you may want to choose the kind of underlayment that’s ideal for you. If you are going to work alone, it’s better to buy synthetic underlayment rolls with 2 squares instead of 10. Such rolls are also good for small-scale projects where you need fewer squares.

Frequently Asked Questions (FAQ)

Q1. What Are The Types Of Underlayment For A Metal Roof?

Answer: There are two types of underlayment for a metal roof – felt paper and synthetic, each with its pros and cons.

The synthetic type is a relatively newer technology and is made by spinning together polyethylene or polypropylene with a polymer. It’s a better and more advanced metal roof underlayment.

Asphalt or the felt paper is made from natural or synthetic materials like natural fibers and wood cellulose, or fiberglass or polyester. The base material is then treated by dipping in asphalt to make it waterproof.

Q2. Does Roof Underlayment Consist Of One Layer?

Answer: Not necessarily. A roofing underlayment could have multiple layers. Between the ceiling of the house and the metal roof, you might have a layer to act as a water barrier, another one for thermal insulation, and yet another reflective layer for insulation.

The reflective layer applies in hot regions to resist the build-up of heat in the building.

Q3. What Is Peel And Stick Underlayment?

Answer: Peel and stick or self-adhesive underlayment is composed of polythene or polyester saturated with bitumen. Bitumen is a mix of rubberized polymers and asphalt. It’s the type of underlayment that’s more resistant to tearing, more durable, and more elastic than the felt type.

It creates a secondary layer of ice and water barrier to protect against rains and ice dams. The peel and stick underlayment is also easier to install, even around valleys, eaves, and rakes.

Q4. How Will I Know If I Need To Replace The Roof Underlayment?

Answer: The first sign that your roof underlayment needs replacing is when you notice water leakage inside your house coming from the direction of the roof. Felt underlayments usually last between 12 and 20 years. So, you could also get a professional roofer to check for leaks.

Q5. Why Is Felt Underlayment More Susceptible To Fire Hazards?

Answer: Felt underlayments are more susceptible to fire hazards because it’s made from the asphalt which, in turn, is made from petroleum, a highly combustible compound. However, to make it fire-resistant, special mineral granules are mixed in it.

But, if a part of the felt is damaged and by any chance, a fire source comes into contact with it, it may create a fire hazard.

Final Words

You see, choosing the best underlayment for metal roof is not that difficult. You need to know the key differences between the felt and the synthetic types and weigh the pros and cons of each before you set out to sign the purchase contract.

Besides, you also need to consider the climate, slope design, and architecture of the building to help you make the right choice. Also in consideration should be if you are going to work alone or with others.

No matter where you are going to construct your home or office, remember that this is a huge investment and that none of the building parts should be neglected. As they say, a stitch in time saves nine and so will a roof over your head if it has the right underlayment to handle all types of situations.

Here’s wishing a long and damage-free life to your building!

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