It is one of the questions we are asked most often, usually by someone weighing up a steel roof for a garage, workshop or garden building. The short answer is that a metal roof is not inherently noisy. What makes the difference is not the sheet itself but what sits beneath it.

Where the noise actually comes from

Rain noise is caused by a thin, unsupported surface vibrating when water strikes it. A single skin of steel fixed straight to widely spaced purlins, with an air gap and nothing to absorb the energy, will drum. The same sheet laid over a boarded deck or an insulated build-up behaves quite differently.

This is why two buildings roofed in the same profile can sound nothing alike. The sheet is rarely the variable.

What quietens a steel roof

• Insulation. An insulated roofing panel puts a rigid core directly behind the outer skin, which damps vibration before it becomes airborne sound. This is the single most effective change you can make.
• An anti-condensation membrane. Our Dripstop sheets carry a felt-like layer bonded to the underside. It is specified to manage moisture rather than sound, but it also breaks up the bare metal surface that would otherwise ring.
• Sheet thickness. We supply 0.7mm as standard for roofing and 0.5mm for wall cladding. The heavier gauge is stiffer and flexes less under impact.
• Fixing discipline. A sheet that is loose at the laps will rattle in wind as well as rain. Fixings should be tight enough to compress the washer without dimpling the sheet.
• Purlin spacing. Longer unsupported spans allow more movement. Closer support reduces it.

Single skin is not always the wrong answer

For a field shelter, a log store or an open-fronted carport, drumming during heavy rain is rarely a problem worth paying to solve. Single skin is cheaper, lighter and quicker to fit, and the building is not somewhere anyone is trying to hold a conversation.

The calculation changes for a home office, a workshop in regular use, a converted garage or any space adjoining living accommodation. There, the cost of insulating is usually repaid in comfort, and you gain the thermal benefit at the same time.

What to decide before you order

Ask how the space will be used, whether it is heated, and whether anyone will be spending extended time in it. Those three answers point clearly to single skin, anti-condensation or a full insulated panel.

If you are unsure which suits your building, get in touch and we will talk it through. All our sheets are cut to your exact length and delivered anywhere in the UK within seven days.