Metal Roof Noise: How to Reduce Rain and Hail Sound (2026)

The number one hesitation homeowners in Pinellas County have about metal roofing is noise. Will it sound like living inside a drum when those summer afternoon thunderstorms roll through? Will hail make the house unbearable? These are fair questions, and the answers depend entirely on how the roof is built.

The truth is that a poorly installed metal roof can be significantly louder than a shingle roof during rain. But a properly designed and installed metal roof assembly produces noise levels that are surprisingly close to conventional shingle roofing. The difference comes down to what is between the metal panel and your living space: sheathing, underlayment, insulation, and attic space all play critical roles in sound control.

In Pinellas County, where heavy rain is a near-daily occurrence from June through September, getting the acoustic design right is not optional. This guide covers everything you need to know about metal roof noise, what causes it, and the specific solutions that work best in our climate.

Why Metal Roofs Are Louder Than Other Materials

To understand how to quiet a metal roof, you first need to understand why it is louder. The physics behind metal roof noise are straightforward.

Metal roofing panels are thin sheets of steel or aluminum, typically 24 to 29 gauge (0.019 to 0.028 inches thick). When a raindrop hits this thin surface, the impact energy causes the panel to vibrate. Those vibrations create sound waves that travel through the roof assembly and into the building below. The thinner the panel and the less material between it and the interior, the louder the noise.

Compare this to an asphalt shingle roof. Shingles are made of layered fiberglass mat, asphalt, and ceramic granules. This composite structure is much denser and more flexible than metal, so it absorbs the impact energy from rain rather than vibrating. The granular surface also breaks up the raindrop impact, scattering the energy instead of concentrating it.

The critical factor is not just the roofing material itself but the entire assembly beneath it. A metal panel installed directly over open purlins (wood or metal framing members with air space between them) acts like a drumhead. The air cavity amplifies the vibrations, creating that characteristic drumming sound. A metal panel installed over solid plywood sheathing with underlayment behaves very differently because the sheathing dampens the vibrations before they can resonate.

Rain Noise in Pinellas County: What to Expect

Pinellas County sits in one of the highest rainfall intensity zones in the continental United States. Summer thunderstorms regularly produce rainfall rates of 3 to 6 inches per hour, with individual storms sometimes exceeding 8 inches per hour in short bursts. This is not gentle Pacific Northwest drizzle. Florida rain hits hard and fast.

During these intense storms, even well-insulated metal roofs will produce some audible rain noise. The question is whether that noise is a pleasant background patter or an overwhelming roar that makes conversation impossible. With proper installation, metal roof noise during heavy Florida rain typically falls in the range of 50 to 60 decibels inside the home, which is comparable to moderate background conversation. Without proper soundproofing, that number can climb to 70 decibels or higher, which is roughly the volume of a vacuum cleaner.

Solid Sheathing vs. Open Purlins

The single biggest factor affecting metal roof noise is whether the panels are installed over solid sheathing or open purlins. This decision alone can account for a 15 to 25 decibel difference in rain noise levels.

Solid sheathing (typically 1/2-inch or 5/8-inch plywood or OSB) provides a continuous solid surface beneath the metal panels. The sheathing absorbs impact vibrations, prevents the panels from flexing excessively, and eliminates the air cavity that amplifies sound. In residential construction throughout Pinellas County, solid sheathing is the standard approach for metal roofing and is required by most manufacturers for warranty compliance.

Open purlins are horizontal framing members spaced 12 to 24 inches apart, with no solid deck between them and the metal panels. This installation method is common on agricultural buildings, pole barns, and some commercial structures. It is less expensive than solid sheathing because it uses less material, but it creates a resonance chamber that dramatically amplifies rain and hail noise. Some older homes in Pinellas County that were converted from open purlin systems to residential use can have significant noise issues.

For any residential metal roof installation in Pinellas County, solid sheathing should be considered mandatory, not optional. The cost difference is relatively small ($1.00 to $1.50 per square foot), and the noise reduction is dramatic. If you are re-roofing an older home that currently has purlins, adding solid sheathing over or between the purlins before installing the new metal panels is one of the best investments you can make.

Underlayment Options for Sound Reduction

The layer between the metal panels and the roof deck (underlayment) plays a dual role: waterproofing and sound dampening. Not all underlayments are equal when it comes to noise reduction, and the right choice can significantly improve the acoustic performance of your metal roof.

Synthetic underlayment (standard): Lightweight polypropylene or polyester fabrics are the most common underlayment for metal roofing in Florida. They provide excellent water resistance and UV protection during installation, but their thin profile (typically 8 to 15 mils) offers minimal sound dampening. For noise-sensitive installations, standard synthetic underlayment alone is not enough.

Peel-and-stick modified bitumen: Self-adhering modified bitumen underlayment is thicker (40 to 60 mils) and denser than synthetic products. It bonds directly to the roof deck, creating a solid connection that reduces panel vibration. The added mass and rubberized composition absorb more sound energy than synthetic alternatives. Many metal roofing manufacturers in Florida recommend peel-and-stick underlayment for both waterproofing and noise control.

Foam-backed or rubberized underlayment: Several manufacturers offer underlayment products specifically designed for metal roof noise reduction. These products combine a waterproof membrane with a foam or rubberized backer that acts as an acoustic barrier. They are more expensive than standard products ($0.50 to $1.00 per square foot) but provide the best noise reduction at the underlayment layer. Products like foam-backed synthetic underlayments can reduce sound transmission by 5 to 10 decibels compared to standard felt or synthetic.

30-pound felt: Traditional asphalt-saturated felt is still used on some metal roof installations. While heavier and denser than lightweight synthetics, it does not offer the same noise reduction as peel-and-stick or foam-backed products. It also deteriorates faster in Florida's heat, making it a poor long-term choice for both waterproofing and acoustics.

Insulation: The Most Effective Sound Barrier

While sheathing and underlayment reduce noise at the roof surface, insulation is where the most significant sound reduction happens. The mass, density, and placement of insulation between the metal roof and your living space determines how much rain noise actually reaches your ears.

Insulation Types and Their Acoustic Performance

Blown-in fiberglass (attic floor): The most common insulation in Pinellas County attics. At R-30 (approximately 10 inches deep), blown-in fiberglass provides good sound absorption across a wide frequency range. It works by trapping sound energy in the loose fibers, converting it to small amounts of heat. For metal roof noise, R-30 or higher is recommended. The attic air space between the insulation and the roof deck also helps by providing additional distance for sound to dissipate.

Blown-in cellulose (attic floor): Denser than fiberglass, cellulose insulation provides slightly better sound absorption per inch of thickness. Made from recycled paper treated with fire retardant, cellulose packs more tightly and has more mass, which is beneficial for blocking lower-frequency sounds like heavy rain impacts. R-30 cellulose is approximately 8 inches deep and outperforms fiberglass of the same R-value for acoustics.

Open-cell spray foam (underside of roof deck): This is the gold standard for metal roof noise reduction. When sprayed directly to the underside of the roof deck, open-cell spray foam bonds to the sheathing and adds mass, damping, and an airtight seal that dramatically reduces sound transmission. A 5.5-inch application of open-cell foam (approximately R-20) can reduce metal roof rain noise by 20 to 30 decibels compared to an uninsulated assembly. The direct contact with the deck means there is no air gap for sound to resonate in.

Closed-cell spray foam (underside of roof deck): Denser and more expensive than open-cell, closed-cell spray foam provides excellent acoustic performance and superior moisture resistance. A 3-inch application provides approximately R-21 and creates a vapor barrier. In Pinellas County's humid climate, the moisture resistance of closed-cell foam is an added benefit. However, for noise reduction alone, open-cell foam is often more cost-effective because its softer structure absorbs more sound energy per inch.

Rigid foam board (above or below deck): Polyiso or EPS foam boards installed above the roof deck (between sheathing and metal panels) or below the deck add mass and thermal resistance. While not as effective for sound absorption as fibrous or spray foam insulation, rigid boards do reduce sound transmission and provide valuable thermal benefits in the Florida climate.

STC Ratings: Measuring Roof Assembly Sound Performance

Sound Transmission Class (STC) is the standard rating used to measure how well a building assembly blocks airborne sound. Higher STC numbers mean less sound gets through. For context, an STC rating of 25 means normal speech can be easily heard through the assembly. An STC of 50 means loud speech is barely audible.

For metal roofing, the STC rating describes the entire roof assembly, not just the metal panel. A bare metal panel alone might have an STC of 15 to 20. Add solid sheathing, underlayment, an attic air space, and ceiling insulation, and the same metal panel assembly can achieve an STC of 40 to 55 or higher.

The key takeaway from these STC comparisons is that a well-built metal roof assembly achieves the same or better acoustic performance as a standard shingle roof. The "metal roofs are loud" reputation comes from bare-bones installations that skip the sheathing, underlayment, and insulation layers that responsible contractors include as standard practice.

Metal Roof Noise Compared to Shingle Noise

Homeowners in Pinellas County often ask for a direct comparison between metal and shingle roof noise. The answer depends on comparing equivalent assemblies.

A standard asphalt shingle roof with plywood sheathing, synthetic underlayment, and R-30 attic insulation produces interior noise levels of approximately 45 to 55 decibels during heavy rain. This is the baseline most people are accustomed to.

A comparable metal roof assembly (metal panels on plywood sheathing, premium underlayment, R-30 attic insulation) produces interior noise levels of approximately 50 to 60 decibels during the same heavy rain. That is a difference of about 5 to 10 decibels, which the average person perceives as "slightly louder" rather than dramatically different.

Upgrade the metal roof assembly to include spray foam on the underside of the deck, and the noise levels drop to 40 to 50 decibels, actually making the metal roof quieter than the shingle roof with standard insulation. This demonstrates that metal roof noise is primarily an insulation and assembly issue, not an inherent flaw of the material.

Hail Noise: A Different Challenge

While rain noise is the primary concern for Pinellas County homeowners, hail noise deserves separate discussion. Hail impacts are louder than rain on all roof types because hailstones are denser and hit harder. On metal roofs, hail creates a sharp, percussive sound that is distinctly louder than rain.

Pinellas County does not experience hail as frequently as inland Florida or midwestern states, but it does occur during severe thunderstorms, typically in the form of small hail (pea-sized to marble-sized). These events are usually brief but can be intense.

The same soundproofing measures that reduce rain noise also reduce hail noise. Solid sheathing, dense underlayment, and spray foam insulation all dampen hail impact sounds. Additionally, thicker gauge metal panels (24 gauge vs. 29 gauge) resist hail denting and produce less noise because they are stiffer and vibrate less.

Cost of Soundproofing a Metal Roof

The investment required to soundproof a metal roof varies depending on how many layers of protection you add and whether you are building new or retrofitting an existing roof. Here is a breakdown of typical costs in the Pinellas County market:

For most Pinellas County homeowners, the best value combination is solid sheathing, premium underlayment, and R-30 or higher blown-in insulation. This approach adds approximately $2.25 to $3.75 per square foot to the roof cost and achieves noise levels comparable to a standard shingle roof. For homeowners who want the quietest possible metal roof, adding spray foam to the underside of the deck delivers premium results at a premium price.

Standing Seam vs. Exposed Fastener: Noise Differences

The two main categories of residential metal roofing have inherently different noise profiles, and understanding the differences helps you make a better choice for your Pinellas County home.

Standing seam metal roofing is generally quieter for several reasons. The panels are attached with concealed clips that allow slight thermal expansion and contraction without stress on the fasteners. This eliminates the "popping" or "pinging" sounds that exposed fastener roofs can produce during temperature changes (a daily occurrence in Florida). Standing seam installations almost always include solid sheathing, which provides the vibration dampening discussed earlier.

Exposed fastener metal panels tend to be louder because they are sometimes installed over open purlins (especially on budget installations), and the screws that penetrate the panel face can become points of vibration and sound transmission. Additionally, as the rubber washers on exposed fasteners age and compress, the fastener holes can become slightly loose, creating rattling during wind events. That said, exposed fastener panels installed over solid sheathing with good insulation can still achieve acceptable noise levels.

Thermal Expansion Noise

Rain and hail are not the only sources of metal roof noise. In Pinellas County's climate, thermal expansion and contraction can produce audible sounds, particularly in the early morning and late afternoon when temperatures change rapidly.

Metal panels expand as they heat up during the day and contract as they cool at night. This movement can create creaking, popping, or ticking sounds as panels slide against clips, fasteners, and adjacent panels. Standing seam systems are designed to accommodate this movement through their clip attachment system, which makes them generally quieter during thermal cycling.

Lighter colored metal roofs (white, light gray, tan) absorb less solar heat and experience less thermal movement than darker colors. In Pinellas County, where roof surface temperatures can exceed 160 degrees Fahrenheit on dark-colored roofs, choosing a lighter color reduces both energy costs and thermal expansion noise.

Retrofit Solutions for Existing Metal Roofs

If you already have a metal roof on your Pinellas County home and are experiencing excessive noise, there are several retrofit options that do not require replacing the roof:

• Add attic insulation: If your current insulation is below R-30, adding blown-in fiberglass or cellulose is the most cost-effective retrofit. Many Pinellas County homes have only R-19 or less in the attic, and upgrading to R-38 can reduce noise by 10 to 15 decibels while also lowering cooling costs.
• Spray foam the underside of the deck: If the attic is accessible, spraying open-cell foam directly to the underside of the roof deck creates a conditioned attic space and dramatically reduces noise. This is the single most effective retrofit for metal roof noise.
• Seal air gaps: Sound travels through air gaps in the ceiling, around light fixtures, at duct penetrations, and through attic access doors. Sealing these gaps with caulk, weatherstripping, or spray foam can reduce sound transmission by 5 to 10 decibels without any work on the roof itself.
• Add ceiling mass: Installing a second layer of drywall on the ceiling below a noisy metal roof adds mass that blocks sound. Using 5/8-inch Type X drywall with Green Glue damping compound between layers can improve ceiling STC by 8 to 12 points.

Frequently Asked Questions

Are metal roofs really louder than shingle roofs?

A metal roof installed directly over open purlins without solid sheathing or insulation can be noticeably louder than an asphalt shingle roof during heavy rain. However, a properly installed metal roof with solid sheathing, quality underlayment, and adequate attic insulation produces noise levels that are comparable to or only slightly louder than shingle roofs. The difference in a well-built assembly is typically 5 to 10 decibels during heavy rain.

What is the best underlayment for reducing metal roof noise?

For noise reduction, a high-density synthetic underlayment combined with a foam or rubberized backer provides the best results. Products like peel-and-stick modified bitumen underlayment add mass and damping that reduce sound transmission. Avoid thin, lightweight synthetic felts if noise is a primary concern, as they provide minimal acoustic benefit compared to thicker options.

How much does it cost to soundproof a metal roof in Florida?

The additional cost to soundproof a metal roof typically ranges from $0.50 to $2.50 per square foot beyond the standard installation cost. Adding solid sheathing over purlins costs $1.00 to $1.50 per square foot. Premium underlayment adds $0.25 to $0.75 per square foot. Attic insulation upgrades range from $1.00 to $3.00 per square foot. For a typical 2,000 square foot Pinellas County home, total soundproofing upgrades range from $1,000 to $5,000.

Does attic insulation help reduce metal roof noise?

Yes, attic insulation is one of the most effective ways to reduce metal roof noise inside the home. Blown-in fiberglass or cellulose insulation at R-30 or higher absorbs sound energy and dramatically reduces noise transmission from the roof to living spaces. Spray foam insulation applied to the underside of the roof deck is especially effective because it adds mass and creates an airtight seal that blocks sound.

Will a standing seam metal roof be quieter than exposed fastener panels?

Standing seam metal roofs are generally quieter than exposed fastener panel systems for several reasons. Standing seam panels are typically installed over solid sheathing, which dampens vibrations. The concealed fastener clips allow slight thermal movement that reduces popping sounds. Exposed fastener panels are more commonly installed over open purlins, which creates a drum-like resonance chamber that amplifies rain and hail noise.