What to do about your roof
The Arizona Republic
During the past few years, many new roofing products have come on the market. Suddenly, choosing materials for that roof can get very complicated.
As for cost estimates, much more is involved than the materials alone. Every home has issues that raise the price: What kind of access does your roof have? How many sheets of underlayment are beneath shingles or tiles? Can you lower the old roofing materials easily onto the ground? Are there electrical wires to watch for? Is the roof more than 15 feet high? What is the condition of your roof deck? Are there rotten wood or joists under shingles or tiles?
Following are advantages and drawbacks of various types of roofing:
Flat roofs –
Flat roofs are usually easier to repair or replace than pitched roofs, and the roofing options are more limited. Many houses in Arizona have both flat sections as well as pitched areas.
Foam: Foam covering has become increasingly popular because it provides the best protection for flat roofs and is easy to work with. It covers a roof completely with no seams or joints to split open and create leaks. But birds can peck holes in the foam that will lead to leaks and water damage.
Foam costs about 10 percent or more than what is called built-up roofing (see below), not including what it costs to tear off an old roof. If your current built-up flat roof is in good condition, foam can be laid over it if special technical preparations are taken at the parapets and for the roof penetrations.
You definitely get what you pay for with foam. Its light color reflects the sun. It insulates your home so your energy bills can be lower; it’s lightweight and can almost last forever. One disadvantage: It must be inspected every five to seven years to ensure that the elastomeric covering is not wearing thin. That covering has to be redone so that the foam does not get “sunburned.” If a foam roof has sun damage, you need a complete foam replacement.
Built up Roofs: This less-expensive style of flat roofing features membrane sheets with sealing on seams as well as around vents, pipes and other penetrations sticking up from the roof. Sometimes it’s called a modified bitumen roof. Basically, it’s rolled asphalt with heat applied so it sticks to the roof. It can be covered with elastomeric material and generally needs replacing every 20 years.
PVC: PVC stands for polyvinyl chloride. It is used to make flexible plastic sheets that are heat-welded together on your roof. This single-ply roofing, sometimes sold under the names Dura-Last or IB, can cost at least 20 to 30 percent more than foam and takes a week to install. It is longer-lasting than foam and comes in light colors; it resists heat and is very energy-efficient. It is installed on a roof over rigid boards of insulation material. Some estimates are that a PVC roof will last 30 years. It needs no regular recoating.
Pitched roofs –
When a pitched roof is covered with clay or concrete tile, it can be difficult to determine what shape your roof is in without an inspection. That’s because the tiles are not really the actual roof; it’s the underlayment of felt under the tiles that keeps out the rain. To check the underlayment, a roofing firm will inspect the valleys on your roof or areas near the chimney and pull up a few tiles. Although many types of tiles can last 25 years or more, the underlayment has to be replaced more often.
Many homeowners may not like the roofing that they have, but making a major change can involve obstacles. In a subdivision where all homeowners have the same roofing, HOA rules forbid a change in style. Going from wood shakes or fiberglass shingles to tile would require bolstering the frame of your house to support the increased weight of the tiles.
Clay Tile: Several kinds of clay tiles are sold in Arizona, including sandcast, two-piece, interlocking and flat. Sandcast is a matte-finished, rustic-looking tile popular for use on high-end homes, for example. Two-piece tile is similar but stronger. Remember that clay tile will last longer if the underlayment is high quality. The best roofers recommend an underlayment of two layers of 40-pound felt as well as modified bitumen roofing in valleys. Another high-quality choice is G-40, a rolled bitumen material, for the entire roof.
In any case, you will probably have to replace your underlayment before replacing the tiles. How can that be done? Generally, if tiles are in good shape, your contractor can remove them and put them back after replacing the underlayment. Roofers call this an R and R for “remove and replace.”
One possible glitch: If some tiles are broken and can’t be reused, you may have trouble finding replacement matches. In part that’s because over the past few years, many clay tile companies went out of business in Arizona. If you have to replace missing tiles with a slightly different color, however, a roofer can install them where they are not easily visible.
Although clay tiles are long-lasting, they can break and crack, as happened in a big hailstorm a couple years ago. They can also shatter if someone walks on them while doing repairs.
Concrete Tile: Concrete tiles are even more indestructible than clay and can last 25 years or more, local roofers say. But these tiles face the same trouble as clay with underlayment. They also can be removed and replaced. Both clay and concrete resist rot and insects.
Wooden Shakes: Wooden shakes are not common in Arizona, particularly in desert regions. In general, except for important architectural considerations, we do not recommend use of wood shakes.
Metal: A newly popular option is metal roofing. One style is made of steel, coated with bits of stone so it looks like clay tile or wood shakes. These roofs are much lighter than clay or concrete and can sometimes be installed over other roofing. They are durable and will not crack, break, curl or fade. They are laid on top of a structure of 2-by-2s because there has to be air flow between the roof below and the metal paneling.
Shingles: Fiberglass shingles can last 20 years or more but have risen in price. Since these shingles are partly coated with asphalt, an oil refinery byproduct, their cost has gone up due to higher prices for oil. Asphalt shingles are lightweight and won’t break when you walk on them. But shingles can blow off during a storm; they tend to absorb heat and discolor in the hot sun.
When hiring a roofing contractor, just as with hiring anyone to work on your home, be sure that person is licensed, bonded and insured. Get the contractor’s state license number and verify his record with the Arizona Registrar of Contractors. Be sure the license is valid and has not expired. Visit www.azroc.gov on the Internet and click on “contractor search.” Check expiration dates on your contractor’s bond or insurance as well.
All this checking is especially important now with so many “storm chasing” roofers who came to Arizona after our last hailstorm. You want a roofer who will be here for the long term and will guarantee his work.
For more do-it-yourself tips, go to rosieonthehouse.com. An Arizona home building and remodeling industry expert for 35 years, Rosie Romero is the host of the Rosie on the House radio program from 8-11 a.m. Saturdays on KTAR-FM (92.3) in Phoenix, KQNA-AM (1130) in Prescott and KAZM-AM (780) in Sedona, KAFF-AM (930) in Flagstaff and KNST-AM (790) in Tucson.