Are metal roofs noisy in the rain?

Not on a house built the normal way. Over solid roof boards, with underlayment, an attic and insulation underneath, rain on a metal roof is a soft wash you hear only if you are listening for it. Where metal is genuinely loud is wherever there is nothing between the panel and your ears, and that matters if you are roofing a cottage with open rafters or a room with a cathedral ceiling.

Why barn roofs are loud

The reputation comes from farm buildings, and it is earned.

A typical barn or drive shed roof is thin steel screwed to wooden purlins spaced a couple of feet apart, with nothing underneath but open air. The panel vibrates between the purlins like a drum skin, and the empty building below is the body of the drum. No insulation, no ceiling.

Put the same rain on the same steel over a house and almost every one of those conditions is gone. The noise is not a property of metal. It is a property of the assembly.

What actually controls the noise

Four things, roughly in order of how much they matter.

The attic and the insulation

This is the big one. In a normal Ontario house, sound from the roof has to pass through the roof boards, cross the attic, get through a deep layer of insulation, and then the ceiling drywall. Insulation absorbs sound as well as heat.

It is why most people hear rain on the windows and in the eavestroughs before they hear it on the roof. If your attic insulation is thin, topping it up does more for roof noise than anything we can do on top.

Solid roof boards under the panel

Plywood or plank boards give the panel something solid behind it, which damps its vibration, and they add mass between the rain and the room. A standing seam panel over sound roof boards behaves nothing like the same panel spanning open purlins.

The underlayment

Its job is keeping water out, and it helps with noise only a little. Ice and water shield is a rubberised membrane with some damping effect, and synthetic underlayment adds a thin separating layer. Useful, but not the main event. Some underlayment and membrane products are marketed specifically for sound damping under metal, and they are worth a conversation where the room below has no attic.

The panel itself

A stiffer panel drums less. 24 gauge is stiffer than 26, and bead ribs pressed into the flat of the pan stiffen it further. That is one more reason we lean toward 24 gauge with bead ribs on prominent roofs, and the trade-off is covered in our 24 vs 26 gauge guide.

Fastening matters too. Some of what people call metal roof noise is not rain at all, it is ticking and popping as panels warm up when the sun comes out. Exposed-fastener roofs pinned through the panel with screws are more prone to it. A standing seam panel held by concealed clips is designed to slide as it expands, which keeps that to a minimum. You may still hear the odd tick on a cold, bright morning. It is not a defect.

The strapping cavity on our Gold system

Our Gold package installs the panels on strapping, which creates a ventilated air cavity between the old surface and the new metal. We explain why that cavity earns its keep in our guide to putting a metal roof over shingles.

Here is the honest bit. With strapping, the panel is fixed to battens at intervals with an air gap behind it, rather than lying on underlayment directly over the roof boards. An air gap behind a thin sheet can, in principle, make it slightly more resonant.

In practice, over a heated house with an insulated attic, the difference at the ceiling is small, because the old shingles and the roof boards are still there under the cavity and the attic and insulation are still doing most of the work. Where we pay attention is:

• Strapping spacing matched to the clip spacing and the panel, so the panel is properly supported
• 24 gauge with bead ribs when the owner has told us noise is a concern
• Rooms with no attic, such as cathedral ceilings and finished half-storeys, where we talk through whether the cavity is right for that section or whether a direct install with a damped underlayment suits it better

If you are noise-sensitive, tell us at the site visit. It changes the specification, and it should be written into it.

Hail, sleet and snow

Hail is louder on metal than on shingles, and there is no point pretending otherwise. Over an insulated attic you will hear a hailstorm, but you hear one on shingles too, and on your windows and eavestroughs.

Sleet and ice pellets make a fine hiss or patter. Falling snow is silent.

The loudest thing a metal roof does in an Ontario winter is shed snow. A slab sliding off a slick panel can make a startling rumble, and it lands with real force. That is a safety and landscaping question as much as a noise one, and it is what snow retention is for. Our guide to snow guards and ice dams covers when you need them.

Cottage bedrooms under open rafters

This is the case where metal can genuinely be louder, and it is common in cottage country.

Older cottages often have a bedroom or main room with a tongue-and-groove ceiling fixed directly to the rafters, sometimes with the rafters exposed, and little or no insulation between the ceiling and the roof. There is no attic. The only things between the panel and your pillow are the roof boards, the underlayment and the ceiling boards.

Under a roof like that you will hear rain on metal. Plenty of cottage owners choose metal partly for the sound. If you would rather not, there are a few levers:

• Check the roof boards are solid and complete. Some old cottages have gapped boards or skip sheathing. Re-boarding over them adds both stiffness and mass.
• Consider a damped underlayment in those sections.
• Ask about insulating from above if the roof is coming off anyway. Adding rigid insulation over the roof boards before the metal goes on is a bigger job: it changes the fascia depth and the trim, and it needs to be designed properly for vapour control and ventilation. But it is the one moment it can be done without touching the ceiling inside.
• Watch the trees. Under pines and oaks, the noise people notice is often not rain but cones, acorns and fat drips falling from branches onto the roof. Our cottage metal roofing page covers the rest of what is different about roofing a cottage.

Small things that cause drumming

A few noise complaints have nothing to do with the roof assembly:

• An upper downspout discharging onto a lower roof. A steady stream landing on one spot drums all night. Pipe it to the lower eavestrough instead, as our guide to eavestroughs on a metal roof explains.
• Drips from an overhang or a satellite dish onto the panel below.
• Loose trim or a vent cap rattling in wind, which is a fastening fix.

If you are noise-sensitive, ask for these

• Installation over solid roof boards, never open purlins, on any heated living space
• 24 gauge with bead ribs in the pan
• An honest look at your attic insulation, and a top-up if it is thin
• A damped underlayment over rooms with no attic
• Upper downspouts routed so they do not dump onto lower roofs
• The whole lot written into the specification, not agreed in conversation

And if you can, sit under a metal roof in a rainstorm before you decide. Five minutes of listening settles it better than anything we can write.

Questions people ask

Is a metal roof louder than shingles in the rain?

Over an insulated attic, not in any way most people notice. The sound is different rather than louder: a softer, broader wash instead of the sharper patter on shingles. The exception is a room directly under the roof with no attic, where metal is more audible than asphalt and the choices above start to matter.

Will I hear rain in a room with a cathedral ceiling?

Possibly, depending on how the ceiling was built. A modern cathedral ceiling with deep insulation between the rafters is usually quiet. A thin, poorly insulated one will let you hear rain on any roof covering, and a little more on metal. Tell your roofer about those rooms before they quote so the specification can account for them.

Can an existing metal roof be made quieter?

Usually, from the inside. Adding insulation in the attic or the rafter bays is the most effective step. On an exposed-fastener roof, loose or failed screws can also add rattling, which is a maintenance fix our metal roof repair crew handles. Changing the underlayment means taking the panels off, so that is a decision for the next re-roof, not a retrofit.

Does snow make noise on a metal roof?

Falling snow does not. Snow sliding off does, sometimes loudly, and a sheet coming off a roof can be dangerous to anyone or anything below. Snow retention holds it in place to melt off gradually, which keeps it quiet and keeps the eave area safe.