The best course is to conduct yearly inspections that can uncover a range of issues.

• Cracked, warped, or missing shingles
• Loose seams
• Deteriorated flashing
• Excessive accumulation of surface granules in the gutters or downspouts
• And other visible signs

Inside your structure, look for signs like cracked paint, discolored plasterboard, or peeling wallpaper. In any case, you don’t want to wait until your roof is leaking or has other serious damage.

First look for leaks, loose decking, or rotten wood in your attic. If your roof is over 15 years old, it may need to be replaced. You also should look out for telltale signs of deterioration.

• Algae growth
• Blistering, buckling, or curling shingles
• Ceiling spots
• Damaged flashing
• Missing granules or whole shingles
• Rot

Not always. Sometimes leaks originate with loose flashing or a small section of roof damage that can be repaired. However, if your roof has failed due to improper installation, poor materials, or an inappropriate system, it probably will need to be replaced.

Basically, you have two options: a complete roof replacement that includes tearing off your old roof and laying down new materials or re-covering your existing roofing materials. If there’s already a re-covered layer on your roof, a professional roofing contractor can determine if your deck can support a second layer.

The cost will vary widely, based on a number of factors.

• The material selected
• The contractor’s rates
• The area of the country
• The time of the year
• And other issues

It’s best to get estimates from three or four reputable contractors in your area and then way those against the quality of the materials and workmanship.

Every roofing material comes with different grades and prices, so make your choice based on your budget and expectations.

Properly installed to fit the maker’s maximum recommended exposure, one square will cover a 100-square-foot of area.

“Exposure” refers to the height of each row of shingles or shakes - the viewable portion of the material once it’s installed.

If you exceed the manufacturer’s recommendations, you may invalidate the warranty. On the other hand, if you want to reduce the exposure you can, but it means you will need more material than first calculated.

There are several variables that affect your roof’s lifespan: the type of roof you have, your local environment, and the quality of maintenance over the years. The American Society of Home Inspectors has compiled a list of roofing material lifespans.

• Asphalt shingles – 15 to 20 years
• Wood shingles or shakes – 10 to 40 years
• Clay or concrete tiles – 20+ years
• Slate – 30 to 100 years
• Metal – 15 to 40+ years

The various roofing material manufacturers warranty their products in a variety of ways, so be sure to see what they offer should their products fail before their time.