Metal roofing has moved well beyond the corrugated garage roof. Standing seam panels now appear on contemporary extensions, garden rooms and new homes, while profiled sheets remain the practical choice for workshops, stables and industrial units. Metal is light, quick to install over large areas and works on shallow pitches where slate or tile would not.
Newcastle Roofs installs and repairs standing seam, corrugated and profiled sheet metal roofs. We cover choosing the right metal and coating, detailing the roof to manage condensation and noise, and repairing existing roofs where fixings, laps or coatings have deteriorated. We will also tell you honestly when a metal roof is not the best choice for a particular building.
Types of metal roof
- Standing seam – long panels joined by raised, folded seams with concealed fixings. Clean lines and few exposed penetrations make it a favourite for modern extensions and feature roofs. It can be laid at low pitches, within the limits set by the manufacturer.
- Profiled (trapezoidal) sheet – the familiar ribbed sheets on commercial and agricultural buildings, fixed through the crown or valley of the profile. Available single-skin or as insulated composite panels.
- Corrugated sheet – the traditional wavy profile, now available in coated steel and aluminium. Suits outbuildings, sheds and buildings where a rural or industrial look is wanted.
Materials include coated steel, aluminium and, for higher-end work, zinc and copper. Each has different weight, cost and expected life, and they should not be mixed carelessly, as some metals corrode when in contact with each other.
Condensation, noise and insulation
The biggest practical issue with metal roofs is condensation. Metal cools quickly on a clear night, and warm moist air from inside condenses on its underside and drips, often mistaken for a leak. A single-skin roof over a heated space needs a properly designed build-up: insulation, a vapour control layer on the warm side and, depending on the system, a ventilated gap or a structured underlay beneath the metal.
Rain noise worries some homeowners. With insulation and a solid deck beneath, a metal roof over a living space is usually no noisier than other coverings. An uninsulated sheet roof over a garage or workshop will be louder, and anti-condensation backing can help there too. If you are roofing a heated room, Building Regulations will apply to insulation levels, and we design the roof to meet them.
Metal roofing near the coast and on exposed sites
Salt air from the North Sea is hard on metal. Near the coast, at places like Tynemouth, Cullercoats and Seaton Sluice, coated steel can corrode faster, particularly at cut edges and scratches. Aluminium or a steel sheet with a coating rated for coastal exposure is often the better choice, and stainless or coated fixings should be specified. Rinsing areas not washed by rain, such as under overhangs, helps the coating last.
Wind exposure also matters on open ground in Northumberland and on hilltop sites. Sheets must be fixed at the spacings the manufacturer requires for the exposure, with suitable laps and closures, otherwise wind can get under edges and lift panels. In conservation areas, a metal roof on a visible elevation may need planning permission, so check with the council before deciding.
Repairing existing metal roofs
Many older sheet roofs can be extended rather than replaced. Typical repairs include replacing corroded or loose fixings, treating and sealing cut edges, renewing lap sealants, replacing damaged sheets or roof lights, and refixing flashings. Where a coating has failed over the whole roof, a specialist coating system can sometimes add years of life. If sheets are rusted through over large areas, replacement is the better option. Older fibre cement sheets that look similar may contain asbestos and need a different approach.
Gutters on sheeted buildings deserve attention too. Valley and box gutters between roof slopes collect leaves and silt, hold water against the metal and corrode from the inside. Clearing them regularly, and relining badly corroded gutters, prevents many of the leaks we are asked to trace on older sheet roofs.
