The flat roof is much more commonly seen on commercial buildings than on residences, but that doesn't mean it is without benefit for homeowners. Nonetheless, if the flat roof isn't constructed properly in all aspects, or if some of its ramifications are ignored, it can be the source of endless headaches. Let's look at some of the distinctions between a flat roof and a sloped roof and why one might be preferable to the other.

A flat roof, though graded enough to drain, must be watertight, whereas a sloped roof is designed not to be waterproof but water shedding. Any roof with a pitch less than 2 in 12 falls in the flat category, for the shedding principle fails below that steepness.

Roof repair is not my thing, but as a home inspector I am on the roof a lot. I determine whether roof repair is called for or is likely to be imminent. The Standards of Practice require me to traverse the roof during the course of an inspection, but there is an escape clause I can exercise not to traverse the roof provided I document the reasons. The number of incidents of someone (including home inspectors) falling off a roof and/or ladder is high enough to warrant erring on the side of safety. So when the roof pitch is steeper than about 8-in-12, or when conditions are bad (e.g., moss), I take precautions, opt out of traversing, and cite safety as my reason. (And then I inspect the roof using alternative methods.)

Whether roof repair, home inspection, or some other calling requires you to ascend a tall ladder, you can't be too careful. There are techniques one can apply to reduce the chance of accidents, and I'd like to share some of these here. Most of these techniques have to do with proper ladder use, but many of the principles can be extended to getting around on the roof for repair or other reasons.

Shingles are the roof coverings I encounter most often in my home inspections. Furthermore, asphalt roof shingles dominate the field, occurring on a large majority of houses, with use of wood and fiber-cement shingles trailing far behind. For this reason, it is worth exploring roof shingles in more detail. Whether you are looking for the best approach to fix a leaky roof, whether you want to determine your roof's condition and life expectancy, or whether your roof is at the end of its useful life and you need to replace it with shingles or some other kind of material, you should find help herein.

If a shingles roof is just one of several new or replacement options you are considering, make sure you don't overlook important factors. The structure must provide adequate support for both live and dead loads, and different materials vary considerably in weight. They also vary in appearance, cost, life expectancy, and maintenance demands. Compare all of these factors and tradeoffs before making a decision.

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.