Angie's LIST Guide to
Installing a New Roof

What are the signs that you need to install a new roof on your house? Should you have a complete tear-off or just add another layer of shingles? How do you decide which roofer to hire?



Do you need to install a new roof?

You might assume you don't need to think about installing a new roof until the old one starts leaking, but if you wait that long it will be more expensive. Why? Because by the time you notice the leak, the structural damage will have already occurred.

Here are some tips to help decide whether the time has come to install a new roof:

These shingles are curled and decayed from age.

These asphalt shingles are curled and decayed from age.

• How old is the existing roof? If installed properly and with good materials, an asphalt shingle roof should last 20 to 25 years, sometimes longer. It also depends on how many shingle layers you have and if it was properly ventilated. If you've lived there for many years and don't know when the roof was last replaced, consider having a roof inspection.

• Go outside and look at the roof. Are the shingle lines still straight or can you see sags or other irregularities? A sag would indicate that the sheathing underneath is rotting. Pay close attention to the valleys, which are one of the most important part of your roof because it's where snow and rain flow to the gutters.

• When you clean your gutters (which you should be doing twice a year), do you find a lot of asphalt granules in the gutter? That's a sign the asphalt shingles are breaking down.

• Do you see cracked, curled or misshapen shingles? As shingles age, they begin to deteriorate. Are any shingles missing? Check to see if all of the tabs are intact.

• Does your chimney flashing consist of roof cement or tar? Chimneys are a potential weak spot on roofs and need to have a long-term, water-tight fitting such as metal flashing.

• Go up in the attic, preferably during or immediately after a good rain, and look for evidence of leaks or moisture. Also check to see if there's any daylight streaming through the roof boards.

If you're starting to see some of these warning signs, have a qualified roof inspector give you a professional assessment.

RELATED: How to Pick the Best Roof Color for Your Home

Tear off vs. overlay

When you start taking bids for a new roof installation, one decision you'll need to make is whether to have the old roof stripped down to the wood decking or simply cover the existing roof with a new layer of shingles. The difference in price will be considerable — homeowners often save 25 percent or more by opting for reroofing instead of a tear off — but is that a good decision?

Roofers disagree on the answer, with some cautioning that the only way to find and repair weak spots is to strip the roof down to the plywood sheathing where they often find water damage that would not otherwise have been discovered.

Another concern about adding a second layer is that asphalt shingles are heavy, so installing that second layer adds weight that the structure must bear in addition to maximum snowfall for that part of the country.

However, both the National Roofing Contractors Association and the Asphalt Roofing Manufacturer’s Association approve reroofing as a general practice where permitted by local building codes. Roofers who do this kind of work say adding a second layer of shingles can be a reasonable option. However, even they caution that reroofing is also more difficult, particularly when installing flashing around chimneys and other potential points of water entry, so the work needs to be done by a roofer with experience in this method.

Factors to consider when making the decision include:

tearing off an old roof to the decking

A complete tear off ensures that any water-damaged sheathing will be discovered, but adding a second layer of shingles can be just as effective and costs less.

  • The pitch (slope) of the roof is at least 4 feet of vertical rise for every 12 feet of horizontal run — perhaps more in regions where heavy snowfall is common.
  • The existing roof needs to be in good condition (other than age) and made of materials that are compatible with reroofing.
  • It's best if the condition of the roof’s underlying structure can be visually inspected from the attic and is not obscured by insulation or drywall.
  • The roofer must strictly follow both the shingle manufacturer’s instructions and local building codes to make sure the warranty applies.

Roofers caution that reroofing also requires shingle installation techniques that differ from the standard methods. For example, during an overlay, shingles are hand-nailed in nested clusters, while for new roof installations shingles are applied in rows using a nail gun.

In any new roof, the weakest areas tend to be around chimneys and other protrusions, as well as in the valleys where two slopes meet. When applying a second layer of shingles, the roofer needs to tear down to the flashing and determine whether to replace the original flashing or tie into it. Making the right decision on each of these points requires a roofer with both skill and experience at reroofing.

In the end, it’s up to the homeowner to decide what type of roof installation is best. Check Angie’s List to find top-rated roofers working in your area and ask for detailed bids on both options before making a decision.

Hiring a roofer

Installing a new roof may be the single biggest investment a homeowner makes. If all goes well, it's an investment that should last 20 to 30 years or longer. But that also makes it a big risk, because while there are many honest, knowledgeable roofers, there are also crooked and incompetent roofers.

That's probably why the roofing category has always been one of the most frequently researched professions on Angie's List. You can search for roofers in your town and read the reviews and ratings submitted by other Angie's List members who have hired those roofers.

When hiring a roofer or other service provider (especially on an expensive job), follow these tips to get the most out of your money:

storm chasers

Watch out for 'storm chasers'
Be wary of roofing repair salesmen who knock on your door after a big storm.
Read more

• Ask the contractor to show you proof of licensing, workers compensation and liability insurance. Write down or copy the contractor license number, which you can then verify with your state or local trade license board.

• Ask for references of past customers in your neighborhood or nearby — and call them. Any roofing contractor who acts offended when asked for references or licensing proof should be viewed with suspicion.

• Be particularly wary of someone who knocks at your door offering a deal, especially if it is after a major storm that's done considerable damage in your area. Although some honest contractors seek work this way, it's also a common tactic employed by scammers.

MORE: 6 Questions to Ask Roofing Companies When Hiring

Is your roof insured and under warranty?

When something happens to your roof, you need to know what's covered by your homeowner's insurance policy and what your roofing warranties cover.

Many home insurance policies do not include coverage for roof damage. The only way to know if your roof is covered is to ask your homeowner's insurance representative and review your policy. Evaluate the fine print on your home’s policy and check for any exclusions.

new roof warranty
This roof came with a 50-year warranty. (Photo courtesy of Angie's List member Linda B. of Huntington Station, New York)

Be sure to ask your insurance company about weather, fire and repair damage. Also, check with your insurance company about their policy for claim payment for roof damage. Insurance companies that employ adjusters for roof repairs can make quicker payments for any roof damage.

Not all roofs need insurance for wind damage. Homes in more rural areas are more susceptible to wind damage. Insurance policies that cover fire damage often include wind damage in the policy.

Roof warranties protect you if the new roof installation is faulty or the roofing materials have a defect. There are two types of warranties, and many highly rated roofers offer both kinds. A manufacturer's warranty covers the roofing materials, while a workmanship warranty protects you if something goes wrong because of the contractor's faulty installation. Often, quality roofing contractors will offer a guarantee on their work for the lifetime of the roof.

MORE: What Does Your Roof Warranty Mean For You?

What does a new roof cost?

roof replacement cost

Considering a new roof installation is one of the most expensive home improvement projects, it's important to look at the various aspects that influence the cost to replace a roof. 

There's a huge price range for the various roofing types available — from asphalt shingles to metal, tile, and slate — and the type of roofing material you choose will be one of the biggest cost factors.  

Angie's List members recently reported spending an average of $11,095 nationwide for a tear-off and replacement of a roof. A metal roof installation averaged $12,236, while roof repairs for various leak issues, shingle replacement, and minor fascia work cost Angie's List members $751 on average. 

Your roof's size and pitch also play an important role in price, as does accessibility to the roof. Get at least three estimates for a new roof installation before hiring, and make sure those estimates take all of these factors into consideration so you're comparing them fairly and aren't surprised by any costs along the way.

MORE: What is the Average Cost to Replace a Roof?


Another option is to make a call to the manufacturer that the roofer requests to use and see what their track record is for warrantys, training, etc. I work with flat roofing and just because someone can buy the product doesnt mean they can offer a valid manufacturer's warranty.

Depending on your location, State and local building codes will require that you use materials that meet certain criteria. Typically, in the Northeast, due to severe frost action, certified Grade materials (e.g., ASTM c1167-11, Grade-1) are required by law.

what colors do u have

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