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Roofers (From CHECKBOOK, Spring/Summer 2014)
 
Go to Updated Ratings of 29 Twin Cities Area Roofers

Checklist 

Familiarize yourself with the elements of your roof and the language of roofing

Get several bids for any major roofing job. Prices different companies quote for the same work often vary by 100 percent, which may represent thousands of dollars. 

Use estimators as your consultants, getting feedback from them to determine exactly what needs to be done. Then go back to them with the final description of what you want and invite them to bid on the work. 

Use our ratings of area roofing contractors, which appear on our Ratings Tables, to find high-quality companies. 

Before using any contractor, ask for proof that it is licensed and carries liability and workers’ compensation insurance. 

Get a copy of the warranty from the manufacturer of whatever roofing materials are used. Also, get a warranty on the roofer’s work, ideally for five years or more; have the roofer write into your contract: “In addition to all other warranties, if roof leaks within five years [or, better still, 10 years], except as a result of accidental damage, contractor will bear the cost of labor and materials to eliminate all leaks.” 

Get a fixed-price contract. Specify using pictures or in words exactly what roof areas are to be covered. Specify other details, such as whether old shingles are to be removed, whether flashings are to be replaced, who is responsible for cleaning up and hauling away debris, and exactly what types and weights of materials are to be used. 

Arrange to pay for the work as late in the process as possible. About half of the contractors we surveyed will allow customers to withhold all payments until the job is complete. Try to arrange to withhold at least a portion of the price until your roof has been tested by stormy weather. 

The high prices of many home improvement jobs are often tempered by the rewards they provide. A room addition or finished basement provides more living space. A new kitchen may inspire you to cook and entertain. New carpet, flooring, furniture, or a new coat of paint improves aesthetics. But unless you’ve let the old one deteriorate to the point where you have buckets strewn about the house, a new roof won’t make your life seem better. 

Your wallet, however, will feel the difference. Roofing work is expensive, and, unless you purchase carefully, you may spend thousands of more-than-necessary dollars to get less-than-satisfactory results. 

How to Find a Reliable Roofer 

Our Ratings Tables include ratings of local roofing contractors. The table shows which areas they serve and which of the major types of roofs they work on. 

Feedback from Former Customers 

The ratings of area roofers from our surveys of consumers (primarily CHECKBOOK and Consumer Reports subscribers), shown on our Ratings Tables, let you check the opinions of hundreds of your neighbors on area roofers. (Our customer survey and other research methods are further described here.) 

Our survey asked consumers to rate roofers they had used “inferior,” “adequate,” or “superior” on the following questions: “doing work properly on the first try,” “starting and completing work promptly,” “letting you know cost early,” “advice on service options and costs,” and “overall quality.” For companies that received 10 or more ratings, our Ratings Tables report the percent of each company’s surveyed customers who rated it “superior” (as opposed to “inferior” or “adequate”) on each of these questions. Our Ratings Tables also report the percent who rated each company “adequate” or “superior” (as opposed to “inferior”) for “overall quality.” 

Several of the roofing outfits on our Ratings Tables were reviewed very favorably by a high percentage of their customers. At the time of our last full, published article, 13 of the 29 companies were rated “adequate” or “superior” overall by 95 percent or more of their surveyed customers; seven were actually rated “superior” overall by 90 percent or more of their surveyed customers. Unfortunately, however, substantial numbers of the customers of some of the outfits listed on our Ratings Tables regretted their choices: seven of the companies were rated “inferior” overall by at least 20 percent of their surveyed customers. 

Complaint Histories 

For firms that were evaluated in our last full, published article, our Ratings Tables also show counts of complaints we gathered from the Better Business Bureau (BBB) for a recent three-year period and complaint rates relative to the volume of work companies do. For more information on reported complaint counts and rates, click here

Payment Policies 

One way to reduce the risk of being dissatisfied is to arrange to pay for most or all of the work only after the job is completed. Withholding payment gives you leverage to ensure that work is done properly and on time. Our Ratings Tables show what percentage of the contract price on a $5,000 roof installation job each company “ordinarily” allows the customer to pay upon completion or later. About one-fourth of the companies allow you to withhold the entire amount until completion, but some require customers to pay at least half earlier. We strongly advise you to choose a contractor that requires no payment before work begins—or certainly not more than 10 percent of the contract price. 

Licenses and Bonds 

Think ahead about obtaining additional leverage in case you’re dissatisfied with a contractor’s performance. A company may seem conscientious and cooperative early in the process, but prove harder to live with later. 

By choosing a contractor licensed by the Minnesota Department of Labor & Industry, you empower consumer protection officials to use the threat of license cancellation as one form of leverage in working to resolve disputes. And because you have taken the care to choose a licensed contractor, you also enhance the chances that the officials will feel you deserve their help. Ask any contractor you are seriously considering to present proof of a currently valid license; then verify by calling the Department of Labor & Industry at 800-342-5354 or by checking its website at www.dli.mn.gov

An additional advantage of dealing with a licensed contractor is that you may be able to collect from the state’s Contractor’s Recovery Fund if you are unable to collect a claim from the roofer. There are limits on what you can collect from the Fund, however. The Fund will not pay more than $75,000 per claimant, or more than $150,000 per contractor, and that amount might have to be divided among multiple customers with similar claims. 

If you wish additional protection, ask your contractor to secure for you a “performance bond” in the amount of your contract price. This will add an extra one percent to five percent to the price of the job, but the bond will cover your full claim. Although performance bond requirements are common in contracts with commercial customers, they are rare in contracts with homeowners, and a responsible but small contractor may have difficulty obtaining one. Nonetheless, this is an option to discuss with potential contractors. 

Proof of Insurance 

If a third party is injured by a contractor working on your home, or if one of the contractor’s employees is injured, you could be liable. The best way to protect yourself is to make sure the contractor carries liability and workers’ compensation insurance. Before signing a contract, require the contractor to show you current “certificates of insurance” for both liability and workers’ compensation; insurance companies readily issue such certificates. Alternatively, ask the contractor to provide contact information for its insurance agent so you can verify that the contractor’s policies are up-to-date. 

Financial Soundness and Stability 

You need to make sure your roofer will be around to finish the job and that you won’t be left fending off the roofer’s creditors who wish to place a lien on your house. 

A good way to assess financial soundness is to obtain—and check—references. Ask for the names of major materials suppliers. Then ask suppliers about how much credit they commonly extend and the contractor’s recent payment performance. 

If your roof has been damaged during a storm, be wary of contractors who appear out of nowhere to offer help. Scads of roofers make their livings chasing storms—traveling from area to area in search of easy-to-obtain business. Some of these companies perform good work, but many do not, and if your newly repaired roof begins to leak a year or two later, it could be hard to track down the out-of-area contractor. 

Warranties 

You may get two types of warranties on roofing work: a warranty on materials from the manufacturer and a warranty on workmanship from the roofer. Many manufacturers also offer extended warranty protection. 

The materials warranties offered by the major shingle manufacturers are very similar. Asphalt composite shingle manufacturers, for example, agree to pay for the cost—including labor—to repair or replace shingles proven to be “defective.” The duration of the warranty varies with the quality of shingles. A manufacturer’s warranty generally begins with a specified period of time (for example, five years) during which the warranty covers the entire cost of replacing defective shingles. After the initial period, the manufacturer’s exposure is reduced on a pro-rata basis each year for the remainder of the warranty’s duration. 

Roofers’ warranties of their labor may not be spelled out as clearly. Some simply say “labor guaranteed for X year(s).” Others say “guaranteed against defects in workmanship for X year(s).” It’s not clear whether these statements mean you will recover costs or have work redone for free only if you can prove that the work was done improperly, or whether you only have to show that the roof leaks. It’s also unclear whether, if the workmanship is defective, the contractor must provide only labor or also required materials. 

You’ll be better protected if the roofer lets you write into your contract, in addition to all other warranties: “If roof leaks within X year(s), except as a result of accidental damage, contractor will bear the cost of labor and materials to eliminate all leaks.” 

Roofers’ warranties most often cover one to two years, but some are in effect for five years or more. Most roofers offer different warranties for different types of roofs and shorter warranties for repair jobs than for roof replacements. 

To supplement roofers’ warranties—and to protect yourself if roofers go out of business and aren’t around to honor their warranties—most manufacturers now offer extended warranties that cover workmanship. To buy one of these warranties, you have to use a contractor that has been approved by the writer of the warranty, which usually involves checking out proper licensure and insurance coverage. Also, the warranty seller will require the roof to be installed according to proper specifications (adequate ventilation, premium felt paper, ice and water protection at locations of likely leaks, etc.). 

Extended warranties usually cost $4 to $10 per 100 square feet of the roof, depending on the length of the warranty. If your roof measures 2,500 square feet, and a typical 20-year extended warranty costs $10 per 100 square feet, you’d pay $250. As with most extended warranties, CHECKBOOK doubts that the value of these manufacturer-offered warranties justifies the cost, but they do represent an additional form of protection. 

Prices 

The quality of a roofer’s work and its financial responsibility should be your primary considerations. No price is a bargain price for a roof that leaks or looks unattractive or is never installed. But once you have identified roofers that measure up on quality factors, price becomes critical. 

Contract to have roofing work done on a fixed-price basis, following an estimate. 

We worked with nine subscribers to get bids on roofing jobs for their homes. As much as possible, roofers bid on the same specifications. The roofer-to-roofer price differences on the same job were striking. 

Table 1 includes examples of different bids for these subscribers’ jobs. For one job, prices ranged from $5,400 to $20,195—a difference of more than $14,000. For another job, quotes ranged from $5,616 to $13,900—a difference of more than $8,000. 

Table 1—Some Roofers Charge a Lot More Than Others
 

Table 1
Some Roofers Charge a Lot More Than Others
Below are price quotes collected by CHECKBOOK’s mystery shoppers for installation of new roofs on average-size homes. So much as possible, each subscriber had each roofer bid using the same specifications.
  Home 1 Home 2 Home 3 Home 4 Home 5 Home 6 Home 7 Home 8 Home 9
Lowest Price Quote $6,650 $5,616 $4,871 $5,400 $6,995 $5,512 $5,300 $6,002 $6,824
  $7,000 $6,650 $5,620 $6,750 $7,700 $5,590 $5,398 $6,476 $6,930
  $7,550 $6,948 $5,800 $6,935 $7,825 $5,800 $5,800 $6,928 $7,000
  $7,795 $7,000 $6,320 $6,950 $8,025 $6,315 $5,895 $7,220 $7,125
  $7,990 $7,333 $6,629 $7,400 $8,210 $6,510 $6,065   $7,560
  $8,023 $7,952 $6,900 $7,680 $8,280 $6,700 $6,236   $7,700
  $8,367 $9,080 $7,220 $7,890 $8,500 $6,735 $6,460   $7,756
  $8,495 $9,770 $7,349 $9,145 $8,750 $6,750 $6,712   $7,925
  $8,599 $9,952 $9,213 $9,325 $8,950 $6,766 $6,750   $8,168
  $8,700 $10,830 $18,000 $9,700 $9,200 $6,800 $7,572   $8,482
  $8,994 $11,200   $10,129 $9,380 $6,800 $7,800   $8,714
  $9,440 $12,752   $10,800 $9,435 $7,055 $8,029   $9,160
  $9,450 $13,800   $11,730 $9,920 $7,125 $8,785    
  $9,529 $13,900   $20,195 $10,500 $7,836 $9,223    
  $10,125       $10,725 $8,097 $10,412    
  $11,840         $8,365      
  $12,771         $8,576      
            $9,323      
Highest Price Quote           $9,344      
Difference Between Lowest Price Quote and Highest Price Quote $6,121 $8,284 $13,129 $14,795 $3,730 $3,832 $5,112 $1,218 $2,336

The message is obvious: Get several bids

Get your bids from companies that rate high for quality. Our experience with roofing bids is that there is no consistency: Contractors, including high-quality contractors, may charge high prices for some jobs and low prices for others. There is little price-quality relationship. 

There’s no firm rule as to exactly how many bids you should get. You can’t know in advance whether the next bid will be lower than others—it could save you thousands of dollars or be higher. Likewise with the third bid. 

Figure 1, based on multiple bids to replace an average-size asphalt composite shingle roof, illustrates what you can expect to save by getting additional bids. 

The likely gain from a third bid is smaller than the gain from getting a second bid. Obtaining a fourth bid is usually even less productive. And while the shape of a curve, like the one in Figure 1, would be different for different jobs, the likely savings from getting three, four, or more bids will readily justify the effort. 

Figure 1—How Much a Typical Consumer Might Expect to Save By Getting More Than One Bid on a Re-roofing Job

roofer bid figure

Here are guidelines on getting bids: 

  • Invite out more companies than you really want to see: Some won’t show up for months, if ever. When you’ve seen enough, call the remaining contractors and cancel. During some periods, especially after roof-damaging storms, you may have to invite many contractors to get even a few to appear. 
  • Use estimators as your consultants. Until you get your first few bids, you probably won’t know exactly what work you need. Ask each contractor for its recommendations and the reasons behind them; then weigh the arguments and settle on your own set of specifications. 
  • Once you have a tight description of your specifications, ask the contractors that have already bid on your job to adjust their bids accordingly; give a copy of the specifications to any additional companies that you wish to bid. 
  • You probably won’t have to be present when estimators arrive, unless you need to point out water damage inside your house. If you won’t be there, email your specifications in advance or leave copies of them. 
  • Get more bids on larger jobs. A 20 percent saving on a $500 job is just $100, but if you can save 20 percent on a $10,000 job, that’s $2,000. 
  • Get additional bids if there are large differences between the first two or three bids. 
  • Get more bids on jobs when labor, rather than materials, comprises a large portion of costs. Contractors pay roughly the same amount for materials, but there may be significant differences in their hourly rates for labor and how much their workers accomplish per hour. 
  • Get more bids if it’s easy—for example, if you’ll be home anyway or can arrange for the roofer to come over while you’re gone. 

For small repair jobs, some contractors work on a time-and-materials basis. If possible, avoid this arrangement; you’re much safer with a fixed-price contract. But if you must pay by the hour, ascertain the hourly labor rate, how many workers it includes, the minimum charge, whether you’ll be charged for travel time, and how partial hours are rounded. You’ll find that getting this information is like pulling teeth. 

How to Deal with Your Roofer 

It’s not enough to choose a good roofer. To get the roof you want when you want at the best possible price, you must also deal with contractors wisely. 

Determine what you need. 

Inspect your roof carefully. Does it all need to be entirely replaced, or are some parts newer and in better shape? Are the gutters in good shape? How about the flashings? Is there rot in the fascias or sheathing? Is your attic properly ventilated? You can get free help from each estimator you consult, as each of them may recommend slightly different remedies. To shop meaningfully, request estimates on the same work from each company. But also ask them to propose variances from the basic work plan, the reasons for these variances, and their effects on the total cost. 

Familiarize yourself with the elements of your roof and the language of roofing

Specify in your contract what you want done. 

Estimators’ proposals are often imprecise, so add specifics before you sign. For example, for an asphalt composite shingle roof— 

  • Specify, using pictures or in words, exactly what roof areas are to be covered. 
  • Indicate whether or not old shingles are to be removed. There are two reasons for removing old shingles before applying new ones: First, additional layers may overload underlying sheathing and structural lumber—especially if you are getting new heavyweight architectural shingles. Second, old shingles can warp as they dry out and age, causing new shingles to appear uneven. Consequently, most local codes prohibit application of more than two layers of shingles, except in unusual circumstances, and roofing over old shingles is less common than in the past because most manufacturers’ warranties don’t cover shingles laid over old ones. On the other hand, it costs less to roof over than to remove old shingles before re-roofing. 
  • If shingles are to be removed, indicate that a new layer of felt must be applied under the shingles, as required by local codes. Also indicate the type and weight of the felt. 
  • Specify the types of shingles to be used—their make, color, shape, wind resistance, and weight. Light colors, which tend to absorb less heat from the sun, may last longer; but there’s no hard evidence on how much longer, and dark shingles may look better on your house. Instead of simple, flat, three-tab shingles—the roofing staple for decades—many homeowners select “architectural” or “dimensional” shingles. These shingles are layered, cut, and colored to provide more depth and shadow lines, and to more closely resemble slate or wood shingles or shakes. Examine a sample of the specific make, color, and style of shingle that the contract specifies. 
  • Specify the warranty on the shingles. Using shingles with a 30-year warranty rather than a 20-year warranty might cost a little extra but spare you, or your house’s next owner, the cost of labor and materials for roof work for an extended period (although we have found no scientific evidence that 30-year shingles last significantly longer than 20-year shingles). Architectural shingles, which are generally heavier than simple three-tab shingles, often have warranties of 40 years or more. 
  • Indicate which, if any, flashings are to be replaced, which are to be reused, and what materials are to be used. Unless specified in the contract, a roofer is not legally required to repair or replace flashings. If you have copper flashings now, most experts recommend leaving them in place. Aluminum flashings, on the other hand, are often replaced because they are frailer than copper and cost less. Specify whether replacements are to be aluminum, copper, or some other material—and what weight they will be. For copper flashings, insist on at least 16-ounce (per square foot) material, and try to get 20-ounce material for valleys. For aluminum flashings, insist on at least 0.032-inch thickness. The heavier the flashings, the less likely that they will be damaged during installation or erode away, and the more likely that they will be reusable in the future. Also specify the width of flashing, to ensure it will protect the slope and angle covered. 
  • Indicate in the contract that membrane will be installed at the edges of eaves and at valleys to prevent damage from ice dams. When ice, snow, and melted water come off the roof from the warm areas over the house, they may freeze—especially at unheated roof eaves, which extend out from the house—forming dams. Once a dam forms, water flowing down the roof backs up under the shingles. To prevent ice dams, the contractor should install a special membrane under shingles. Around the edges of the roof, the membrane will need to extend from the edge of the eaves up beyond the house wall. A width of two feet of membrane is the minimum; discuss with roofers whether it would be desirable to add an additional two to four feet of membrane to prevent ice dams. Underneath valleys, three feet of membrane coverage is desirable. 
  • Specify whether any ventilation is to be added. Proper ventilation of your attic releases the water vapor that rises through your house, reducing the chance of rot. Also, good ventilation of hot air from your attic during summer can keep your house cooler. Press roofers to explain their recommendations regarding ventilation. There is debate within the industry as to how much ventilation is desirable. Local building codes specify minimum ventilation requirements. The best approach usually is to put vents in both ridges and soffits. Ventilation also is important for preventing ice dams. A good system will include vents that admit cold air under the entire roof and good insulation above ceilings to keep warm air in the house from entering any space immediately beneath the roof. 
  • Specify whether the shingles are to be algae-resistant. Growth of algae, especially in damp and shady areas, can be an eyesore. Shingles can be manufactured incorporating tiny flecks of zinc or other materials that retard algae growth. Algae can be treated after the fact by washing down the roof with readily available chemicals—but you can avoid all that by installing algae-resistant shingles. 
  • Specify that the contractor is responsible for a complete cleanup. Nails and cuttings of flashings are hard to clean up and can be hazardous. Many contractors use magnetic devices to collect metal. Also request a daily cleanup—so the area won’t become a mess over the course of the work, and you can see early on how well the roofer cleans and be prepared, if necessary, to supervise carefully. Poor cleanup is a problem cited again and again by subscribers we survey. 
  • Write in a requirement that the contractor will haul away all debris; otherwise, you may be stuck with messy piles you have no legal right to force the contractor to remove. It costs contractors about $100 to haul away shingles removed from an average-size roof. 
  • Indicate whether metal drip edges are to be installed at the eaves and the rakes. At about $1 to $2 per linear foot, these edges, which prevent water from curling back under the shingle edge to reach the wood, are generally a good investment. 

Be similarly specific on other types of roofs. For example, specify the grade of shakes or shingles to be used on a wood roof, make and composition of concrete or synthetic shingles or tiles, number of layers and type of stone for a built-up roof, type and weight of metal and paint for a metal roof, and materials and application techniques for a modified bitumen or single-ply flat roof. 

Determine if your roof work requires a permit and inspection; if so, specify in the contract that the company must secure a permit, and that the work must be inspected and approved before your final payment. 

Check with your local building inspection office to determine whether a permit is necessary for your roof work. 

Indicate in the contract when work will begin and how long it will take. 

Given frequent customer dissatisfaction with delays (as reflected in our customer survey findings), you should have the right to get out of a contract and find another roofer if your original contractor proves too slow. 

Spell out a fixed price for the work and a formula for covering contingencies. 

While you should be able to obtain a binding contract at the estimate price, most companies will insist on provisions for extra charges if they will find damaged fascias, sheathing, or structural lumber. Most of the contracts state that required carpentry will be performed on a “per foot” or “time and materials” basis. Make sure your contract states how charges will be computed, typically per-square-foot or per-linear-foot. 

Pay for your work as late as possible; indicate payment schedule in the contract. 

About one-fourth of the roofers we surveyed allow customers to pay nothing until the entire job is completed. Although companies have standard policies on payment scheduling, most will alter them to accommodate customers with good credit standing. In particular, never let your payments get ahead of the completed work or pay in full until the job is completed. Press for enough leeway in your payment schedule so that final payment isn’t due until your house experiences stormy weather. 

Make sure the contractor carries workers’ compensation and general liability insurance. 

Before you sign a contract, ask to see certificates of insurance. If the insurance documentation is not available when you sign, write into the contract: “Contractor is required to provide homeowner with certificates of workers’ compensation insurance and personal liability and property damage insurance. Work is not to commence, and no payments are required, before such certificates are provided.” In addition, write that you “will be held harmless for any damages which would be covered by general liability or workers’ compensation insurance.” 

Specify in the contract whether subcontractors will be used and, if so, their identities. 

Write in the contract: “No subcontractors other than those listed are authorized to do work on homeowner’s premises, contractor is not authorized to give any other subcontractors access to homeowner’s premises, and homeowner is not liable for payment to any other subcontractors.” 

Arrange to pay for work only after you receive evidence that subcontractors and suppliers have been paid. 

A subcontractor, supplier, or worker may be able to get a lien on your house if the roofer does not pay for labor or materials used. To protect against that possibility, write into your contract: “Prior to each payment, contractor must provide homeowner lien releases covering work to which the payment applies. Each release must state the name of the company or individual making the release, releasing party’s address, materials or services supplied, amount contractor has paid for these supplies or materials, and address of homeowner’s roof, and it must be signed by the releasing party.” 

Press for a strong written guarantee. 

On asphalt composite shingle roofs, manufacturers’ guarantees range from 20 years to 50 years. On built-up, modified bitumen, or single-ply flat roofs, warranties range from less than 15 to more than 25 years. Roofers’ guarantees of their workmanship usually run from one to two years, but you may be able to get one for five or 10 years, or even longer. 

If possible, be at home some of the time when the work is being done. 

If you are at home, you can detect early any misunderstandings about the materials to be used and spot gross flaws in workmanship. (See examples below.) 

Leave a number where you can be reached. 

Things will go more smoothly if your contractor can reach you quickly should problems arise—such as damaged sheathing or an unexpected second layer of old shingles. 

If possible, give the roofers access to a toilet, cold drinks, and other amenities. 

Keep records. 

Maintain a file that includes the contract and specifications, any contract modifications, invoices, canceled checks, and lien releases from subcontractors and materials suppliers. 

If you are not satisfied with your roofer’s work, complain. 

First, negotiate directly with your roofing contractor. If that doesn’t work, complain to a complaint-handling consumer agency. 

Things You Can Do to Keep a Long-Lasting Roof Over Your Head 

You can save money by inspecting your roof regularly to spot incipient problems. And you can save by making simple repairs yourself. 

Be Careful 

You won’t save money, however, if you injure yourself or damage your roof. A few tips— 

  • If your roof is steep or made of wood or slate, stay off of it. There’s just too much risk that you could fall or damage the roof by breaking shingles. 
  • Even if it’s safe to walk on, stay off your roof as much as possible. It is easy to crack shingles or pull out nails, particularly if shingles are warped. Much of the repair work roofers do takes place shortly after new TV antennas or satellite dishes are installed or removed. Some disreputable roofers have turned the damage from careless roof-walking to their advantage: They come out for a minor repair, or offer a free inspection, and advise that a complete re-roofing job will soon be in order. By walking roughly on the roof, they ensure that their prophecies are soon fulfilled. 
  • If your roof is safe to walk on, wear soft, rubber-soled shoes such as tennis shoes. These are best both for the roof and for your own safety. 
  • Don’t work on the roof in wet or windy weather. A wet roof or ladder can be dangerously slippery, and wind can easily knock you off balance. Make sure you don’t have wet grass or mud on your shoes. 
  • Don’t put your weight on loose shingles or weak spots through which you might put your foot. 
  • Make sure neither you nor your ladder touches a power line. 
  • Lift your ladder carefully, and position it properly. Put the bottom end against the house; from the top end walk toward the house lifting the ladder over your head until you reach the house and the ladder is upright; then move the bottom end away from the house about one-fourth of the ladder’s length. To make it easier to step off of and onto the ladder, extend the top of the ladder at least three feet above the edge of the roof. Climb the ladder by stepping onto the center of each rung, with both hands on the sides of the ladder. Tie off the ladder to the gutter to prevent it from being blown over. 
  • When replacing damaged shingles, make sure the newly installed shingles lay flat over older ones. Also, try not to over-bend existing shingles that do not need to be replaced. If you bend shingles too much, they’ll crack or split, and you will have to replace them also. 

Be Vigilant 

Inspect your roof at least annually and after major storms, even if you don’t notice leaks. 

If you have an unfinished attic or crawl space, you can do the most important work from the inside. Look for evidence that water has come into contact with the rafters or sheathing. Poke at dark spots to determine if they are rotten. Examine areas where vent pipes, chimneys, skylights, or other elements pass through the roof. If you spot a hole in the roof, jam a length of wire up through it so you can find the hole from the outside. 

If you have a finished attic, your task is more difficult. Look for signs of water damage on the ceiling and walls, but the location of the damage may be far from the leak that caused it. Water often passes through a leak and runs along rafters, dripping off only when it hits an irregularity or obstruction. You can spot problems you can’t locate from inside only with an outdoor inspection. 

Begin an outdoor inspection by checking gutters and the foundation area for fallen shingles. Then look over the roof for missing or damaged shingles (you may be able to do this from the ground with binoculars). If you see water damage on an inside ceiling or wall, try to locate the point on the outside immediately above this damage, and then carefully work back and forth up the roof looking for the culprit leak. Check that flashings around chimneys, vents, and other protrusions have not developed holes or pulled loose. 

In addition to spotting leaks and water damage, your inspection will reveal whether the entire roof is due for replacement— 

  • A roof of asphalt composite shingles (which may have either a fiberglass or natural fiber base) needs to be replaced when it has eroded away; first the granules on the surface disappear and then the shingles themselves wear down. The first places to wear out are the surfaces below the decorative cutouts or at the ends of shingles. When holes have eroded through the shingles, abundant leaks are imminent. Although asphalt composite shingle roofs typically last more than 20 years, a roof can last less than 15 or more than 50 years depending on how hot the roof gets, the quality of the original roofing materials, and other factors. Even before holes appear, your roof is on its last legs if shingles appear gray and bloated, and if a piece of shingle crumbles easily between your fingers. 
  • Wood shake or shingle roofs may go bad from drying out and splitting or warping. As shingles curl, they pull out nails and blow away. When you begin to lose shingles, it may be time for a new roof. Wood shake or shingle roofs occasionally last as long as 50 years, but can fail much faster if located in a shady area where dampness, rather than drying out, is the problem. Under these circumstances, you may need to have a roofer treat your roof with a preservative spray every three to five years. It is not uncommon for roofs that cannot dry between rains to become mossy and rotted within 10 years. 
  • Tile or slate roofs can last indefinitely (though individual pieces may have to be replaced). 
  • Metal roofs need to be replaced when they become riddled with holes too difficult to patch; if maintained properly, they, like high-quality slate and tile roofs, should last indefinitely. 
  • Built-up roofs (composed of layers of hot bitumen and roofing felt, usually topped with stone) need to be replaced when they become so dried up and cracked that multiple leaks develop. Other telltale signs are blisters and places where the layers have delaminated. A four-ply built-up roof should last 20 years or more. 
  • Problems with single-ply and modified bitumen roofs usually occur at seams and around drains. Look for separation at seams and bubbling or cratering of the membrane. Single-ply and modified bitumen roofs should last 20 years or more. 

Temporary Solutions 

If you discover a leak, you can easily apply a temporary remedy. 

One option is an emergency patch using roofing cement, available from most hardware stores. Apply the compound generously to the roof surface, even if it is still wet. 

Another option for shingle roofs is to slide a piece of galvanized steel, copper, or aluminum under the shingle above the location of a leak. The piece of metal should be large enough to cover the leaking area so that water will be carried away from the leak. 

Repairs 

There are also permanent repairs that some homeowners can comfortably make. 

Shingles 

If you find loose asphalt composite shingles, remove the loose nails, drive in new nails, and cover the old holes and the heads of the new nails with roofing cement. If asphalt composite shingles are merely warped, hold them flat with a spot of roofing cement about the size of a quarter. 

Replacing a shingle, if necessary, is more difficult. Very carefully lift the shingles that lie over the bad shingle, remove the nails holding the bad shingle, remove the shingle, insert a new one, and replace the nails. 

Built-up Roofs 

If there is a small defect at a bubble in a built-up roof, you may be able to repair it by slitting the bubble, cleaning out under the bubble with a trowel or putty knife, sliding cement in under the bubble, pushing the bubble down, driving in a row of nails on each side of the slit, and then covering the area with a layer of cement, a layer of roofing felt nailed around the edges, and a second layer of cement. 

For a larger defect in a built-up roof, the procedure is more difficult. Cut out a square of roofing material containing the defect. Cut out the area one layer at a time, with each deeper square smaller than the one above. Then cut new squares of felt to fit and put them in place, starting with a layer of cement and alternating cement and felt until you have replaced each layer. Drive nails around the perimeter of the top patch; then apply another layer of cement, another larger piece of felt to cover the whole area, and finally one more layer of cement. 

Metal Roofs 

Small holes in tin or galvanized steel roofs can be patched with a spot of solder. Larger defective areas in these roofs can be patched with a square of tin soldered around the edges or with a piece of canvas. If canvas is used, apply a coat of paint as adhesive, then the patch of canvas, and then two or three more layers of paint. 

For small holes in aluminum roofs, use aluminum-pigmented caulking compound. Larger holes (one inch or more) can be patched with a piece of aluminum. Coat the patch with the aluminum-pigmented caulking compound, and hold it in place with sheet metal screws coated in caulking. 

Flashing 

Many cracks in flashing can be repaired, temporarily at least, with a layer of roofing cement. Cement can also be used to fill small joints where flashing has pulled loose from a chimney; simply scrape out the old mortar or cement, put the flashing back in place, and fill the joint with cement. 

Moss and Algae Damage 

Moss or algae growth can be a problem for some roofs, particularly wood shingle roofs. When moss or algae grows on a roof, it holds in moisture and can cause shingles to rot. Moss also can work down to the sheathing, causing structural deterioration. You can remove moss or algae growth by applying a commercial cleaner with a garden hose and/or by using a power washer. 

Re-roofing 

Homeowners who feel comfortable tackling more difficult repairs may, for example, replace damaged sheathing and rafters and do their own re-roofing. Many books and periodicals about more difficult jobs are available in libraries and bookstores. 

Don’t take on an entire re-roofing job unless you’re in excellent physical shape, unafraid of heights, well-informed about building construction, and willing to do very hard, tedious work. A bundle of shingles weighs about 70 pounds, and a typical roof might require more than 60 bundles, each of which has to be lifted to the roof. Also be wary about re-roofing on a steeply pitched roof (more than five or six inches vertical for every 12 inches horizontal), a roof that requires new structural work underneath, or one with numerous dormers and other obstructions. Don’t even consider putting on a built-up roof, and think twice about installing a tile roof; the tools and skills required for such roofs are beyond the reach of most homeowners. Finally, remember that thousands of dollars worth of damage can result if your house has no roof when it rains. Although you can provide temporary covering to avoid or minimize damage, professional roofers can almost certainly work faster than you can. 

Extra Advice:
Common Roofing Mistakes 

You’ll more successfully choose and deal with roofers if you’re aware of all that can go wrong. 

Substructure 

  • Where water has leaked and sheathing has rotted, shingles are simply nailed onto the rotten sheathing. The nails will pull out and shingles will come loose. 
  • Unseasoned materials are used to replace sheathing. The materials will shrink, causing shingles to buckle. 
  • The attic is not properly insulated or ventilated. The central part of the roof will be warmer than the overhang, causing snow and water to flow to the overhang and then freeze. The resulting “ice dam” may cause water to back up under the shingles and leak into the house. 

Flashings 

  • At points where two planes come together, flashing is not put into place or woven valleys of shingles are not used. Leaks will occur at the joints. 
  • Old flashings are reused although they are corroded, eroded, or punctured. They will leak. 
  • No counterflashing is used, or what is used is not properly embedded in the mortar or adequately attached. Counterflashing should be installed over flashing materials to keep flashings dry; without it, water will leak past the step flashing. 
  • Valley flashings are too narrow. In a heavy downpour, water will wash up under the shingles and turn back down under the flashings. 
  • Flashings are not made of heavy enough material. They will crack, puncture, or erode away, causing leaks. 
  • Instead of a series of short- to medium-length pieces stepped over one another, flashings consist of long pieces, nailed at various places along their length. With expansion and contraction caused by temperature change, the metal will fatigue and split or nails will pull out. 

Nails 

  • Nails are too short. If nails are not long enough, they may pull loose.  
  • Nails do not have barbed (or otherwise deformed) shanks. They may pull loose. 
  • Nail heads are too small. They may puncture the surface of the shingles, hastening deterioration and leaks. 
  • Nails are driven into knotholes or spaces between sheathing boards. They will work their way up, forming lumps in shingles. 
  • Too few nails are used. Shingles may come loose in wind or with repeated temperature changes. 

Shingles 

  • Successive courses of shingles are not overlapped, as required for the slope of the roof. Water will back up under shingles or go through nail holes. 
  • Cutouts or edges of shingles on successive courses are not adequately spaced, or openings of one course are too near nail holes on the course below. Water may weave from an opening on one course down through a nearby opening or nail hole in the course below, causing leaks. 
  • Too little space is allowed at joints of wood shakes or shingles. They may swell and buckle in damp weather. 
  • Shingles or slates are too heavy for the framing. Sagging of the roof may damage shingles or create leaks where shingles do not lie properly. 
  • Damaged or cracked shingles are used. They may leak. 
  • In a new roof that is applied on top of an old one, tops of shingles are improperly placed against butt ends of shingles on the roof. The roof’s surface will appear uneven. 
  • The courses slant or the cutouts and edges are improperly aligned (neither random nor regular). Appearance suffers. 
  • Bulges and warps in shingles of a previous roof are not flattened. Appearance suffers and leaks may occur. 

Miscellaneous 

  • Gutters sag, are loose, do not slope adequately, or are installed too low. If gutters overflow, or if water flowing from the roof overshoots gutters, it may cause water to enter the house. 
  • A built-up roof is applied over a metal roof. The metal will expand and contract, tearing the felt. 
  • Bituminous paint is used on a metal roof. It may form bubbles, allowing the metal to rust underneath. 


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