I see a metal roof in maybe one out of fifty inspections. Because a metal roof is more expensive than other kinds--except for slate and clay--this is not surprising. But the burst housing bubble and the Great Recession have resulted in far fewer home sales (and consequently fewer home inspections). Those fortunate enough to hang onto their houses are apt to stay in them a lot longer than they had planned. This means that they are more likely to have to face roof repair or roof replacement themselves rather than letting the next owners deal with it. And this implies that average roof quality and life expectancy may increase. So I'm expecting to see a slate, clay, or metal roof more often in the future.

Is a metal roof something you should consider for your home? Do you desire a roof with a long lifespan (common warranties range from 25 to 50 years) and low maintenance? Is the higher upfront cost worth the peace of mind and long-term savings? What other roof materials besides metal should you consider? Let's see if we can answer these questions.

Metal Roof Advantages

The advantages of choosing a metal roof over other roofing systems are plentiful. First and foremost, such roofs are lightweight, strong, and rigid. Unlike slate or clay roof tiles, the material is not brittle nor is a metal roof as expensive as a slate or clay roof. Though modern treatments dissuade asphalt or wood roofs from catching fire, metal is plain non-combustible. The metal roof sheds snow and ice well, and typically has fewer joints than other roofing. In fact, though usually applied on steep roofs and thus designed to shed water, metal can be used on a flat roof (especially if small in area) in which standing seams help form a watertight skin.

Metal Roof Disadvantages

The primary metal roof disadvantage is the tendency to rust. (Some metals are more susceptible to rust than others.) Because metal expands and contracts, if installers don't provide adequate allowance, the roof will buckle. Another disadvantage is the cost, even though a metal roof is less expensive than one made of clay or slate. One should avoid walking on a metal roof, which can make maintenance (such as it is) challenging. And there can be a noise factor, though most people do not find the noise objectionable.

Metal Roof Configurations

The material ranges from copper and zinc at the high end to galvanized steel at the low, with several options in between; the units are shingles and sheet metal panels. Metal roof shingles have high exposure (i.e., little overlap), are usually treated to deter rust, and may exhibit acrylic, baked-on enamel, or stone granule coatings. They are often designed to imitate wood shingles, wood shakes, or clay tile. Metal roof panels are typically placed with joints running vertically down the surface and with flat, standing, or battened seams.

What we have discussed should give you plenty to think about in planning for your next roof. Besides metal, roofs are made of asphalt, wood, slate, clay tile, concrete tile, and fiber cement shingles. All materials and designs have their trade-offs in terms of quality, cost, maintenance, and lifespan. Consider all aspects carefully and find a solution that works for you.

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Tags: ASHI, Flat Roof, Home Inspection, Home Inspector, Metal Roof, Roof Repair, Roof Shingles, Roof Tiles, Washington State

Published on May 19, 2011 | Comments: 0