Lifespan
Shingles age through wear. The sun dries out the asphalt, the granules come off little by little, and then the shingle becomes brittle.
Metal ages differently and lasts 40 years or more, depending on the manufacturer and installation. Its fasteners and seams need watching, and its finish fades over the years. A shingle roof gets redone once or twice during the life of a metal roof.
Budget
Metal costs more to buy and to install. The material is more expensive, and the work calls for roofers used to it and for special tools.
Ask for a quote for each of the two materials, for the same work, to see the real gap on your roof.
The math changes over a long period. If you stay in the house a long time, a metal roof can save you a full replacement. If you plan to sell in a few years, it is less certain that the upfront cost will come back to you.
Noise
People picture metal as noisy in the rain. Metal is noisy on a shed or a barn, where it is screwed to strapping with nothing underneath.
On a house, metal generally sits on solid decking and an underlayment, above an insulated attic. The sound of rain is well dampened. If the question worries you, ask us for addresses of metal roofs you can go see from the street.
Snow and ice
The smooth surface of metal lets snow slide off. Sliding snow is an advantage for the load on the roof, and a risk on the ground. A slab of snow that lets go can fall on an entrance, a car, a balcony or the neighbour's lot.
Snow guards go above doors, walkways and parking spaces. On the tight lots of the island, their placement is settled in the quote.
Repairs and appearance
- Repairs. Replacing three shingles is simple. Replacing a dented metal panel, or matching the same colour ten years later, is less so.
- Appearance. Metal gives a clean style that suits some houses and clashes on others. In a heritage area, check with your borough what is allowed.
Frequently asked questions
Is metal always a better choice than shingles?
No, metal is not always a better choice than shingles. Metal lasts longer, but it costs more up front and needs specialized installation. For an owner who plans to sell in the medium term, or for a simple roof that is easy to redo, shingles remain a sensible choice.
Can a metal roof go over shingles?
Some metal systems can go over shingles, but you then give up inspecting the decking and fixing what lies underneath. Ask us what the metal manufacturer requires and what we recommend for your roof.
Do you need to clear snow off a metal roof?
A metal roof rarely needs snow clearing. Snow slides off on its own on a steep enough slope. The real concern is where the snow lands. Well placed snow guards protect entrances and walkways.
Which roof lasts the longest?
A metal roof lasts the longest. Depending on the manufacturer and the quality of installation, a metal roof lasts 40 years or more, compared with 15 to 30 years for asphalt shingles. On a flat roof, where neither one is installed, an elastomeric membrane lasts 25 to 35 years.