Archive for April, 2010

What Function Does Shingle Underlayment Serve?

April 29, 2010

What function does shingle underlayment serve?

An underlayment, commonly known as roofing felt, will:

• Protect the roof deck from moisture prior to shingle application

• Provide a degree of backup protection in the event water gets under roofing shingles.

Some local building codes and UL standards require that a shingle underlayment be installed.  Ask your roofing contractor if this is the case in your area.  Also, some manufacturers offer a special underlayment product which prevents leaks caused by water backup from ice dams—a common condition in many winter snow areas.  Protection against ice dams can be obtained by using a waterproofing shingle underlayment at the eaves or lower edges of the roof, in addition to installing adequate ventilation and proper insulation in the attic floor. (See Protecting Your Home From Ice Dams) Ask your roofing contractor about these specialized underlayments.

Need to Know More?

We hope this months posts have provided you with some insightful information regarding the re-roofing process.  Our intention is not to overwhelm you with information, but rather offer you a reliable resource for easy reference.  If you have any questions or comments, we would be happy to hear from you.  In addition, if you did read our “‘Choosing a Roofing Contractor” article, or if you would like any other information on specific products, please write or call us at: 612-617-1717
Mailing Addresses
110 Bank Street-Suite 406
Minneapolis MN  55414

Why Does It Mean That A Roof Should Breathe?

April 27, 2010

Why is it said that a roof should breathe?   How can you determine if the roof is properly ventilated?

When roofing contractors say a roof should breathe, they are usually referring to the ventilation system beneath the roof deck.

Most shingle warranties require a lot of ventilation—as much as one square foot of net free ventilation area for each 150 square feet of floor space to be vented or one square foot per 300 square feet when both ridge and soffit ventilators are used.

An effective ventilation system will help:

• Reduce attic heat buildup

• Reduce attic moisture and condensation

• Prevent weather infiltration, i.e., drifting snow, wind-driven rain

• Prevent ice dam build-up (See  ice dam discussion)  Even if you feel you have had satisfactory ventilation performance with your old roof for as long as 20 years, it might be necessary to add ventilation with your new roof to meet the standards mentioned previously.

Why is it said that a roof should breathe?   How can you determine if the roof is properly ventilated?

When contractors say a roof should breathe, they are usually referring to the ventilation system beneath the roof deck.

Most shingle warranties require a lot of ventilation—as much as one square foot of net free ventilation area for each 150 square feet of floor space to be vented or one square foot per 300 square feet when both ridge and soffit ventilators are used.

An effective ventilation system will help:

• Reduce attic heat buildup

• Reduce attic moisture and condensation

• Prevent weather infiltration, i.e., drifting snow, wind-driven rain

• Prevent ice dam build-up (See the following question for ice dam discussion.)  Even if you feel you have had satisfactory ventilation performance with your old roof for as long as 20 years, it might be necessary to add ventilation with your new roof to meet the standards mentioned previously.

Does The Slope Of The Roof Limit My Choice In Shingles?

April 22, 2010

What is roof slope?  Does the slope of the roof limit the choice of shingle that can be used?

The slope of the roof is measured by the rise versus the run, or the number of inches vertically by the number of feet horizontally.   Some roof slopes can limit the choice of shingles that can be used.

For Instance:

• A roof slope below 2/12 (2 inches per one foot) cannot use shingles.

• Roof slope between 2/12 and 4/12 require low-slope application techniques, including application of waterproofing underlayment as appropriate.

• Roof slopes above 21/12 require steep-slope application techniques.

Your roofing contractor should consult the application instructions found on each shingle bundle wrapper or installation instructions supplied separately for further details.

Is It Always Necessary To Tear Off Existing Shingles Before Reroofing?

April 20, 2010

Is it always necessary to tear off existing shingles before reroofing?  If they are torn off, who is responsible for the disposal of the old shingles?

There are two options available for re-roofing installations.  One would be to tear off the old roof before applying the new one (tear off).  The second would be to lay new shingles over the existing roof (lay over).  While the second choice is the less expensive of the two options, it is not necessarily always the best choice.

There are advantages to tearing off the old roof before installing a new one.  For example:

• If there are any defects in the roof deck, they will be revealed when the roof is torn off.

These defects should be repaired before applying the new roof.

• If condensation problems exist in the attic, they too will be revealed when the roof is torn off.

Properly designed attic ventilation can then be installed in order to help eliminate such problems.

• When the old roof is torn off, waterproofing shingle underlayment can be installed before applying the new roof.  This will help protect against leaks created by cyclical ice damage and wind-driven rain.

• Tearing off the old roof and starting with a clean deck before reroofing may result in a smoother finished roof system.

Although there is added cost to these advantages, each lessens the likelihood that the validity of the manufacturer’s shingle warranty will be impaired.  If the old roof is torn off, your contractor should be responsible for the cleanup and disposal of the old shingles, but make sure your contract states this clearly.

If you do plan to re-roof over existing shingles, first check if your local building codes limit the number of roof layers that can be applied to a residence in your area.  Your roofing contractor will know the pertinent code requirements.

Selecting A Roofing Product Part Part 3 What Does The UL Fire Resistance Rating For A Shingle Mean?

April 15, 2010

What does the UL fire resistance rating for a shingle mean?

The Underwriters Laboratories Inc. (UL) ratings signify that the shingles were manufactured to pass a certain set of standards to qualify as fire resistant.  Organic shingles carry a UL Class C fire resistance rating.  Fiber glass shingles carry a UL Class A fire resistance rating.  Either is appropriate for residential applications.   Some local building codes may have ordinances specifying a certain UL Class for your residential area.  Your roofing contractor or local building codes officer can tell you what the requirements are for your particular area.

Selecting A Roofing Product Part 2

April 13, 2010

What type of warranty should I look for?  Aren’t they all the same?

Warranties range from 20 years to lifetime.  The length of the warranty is an indicator of performance and value. The upfront coverage in the first few years following application is also very meaningful.  This is the time when, according to contractors, problems caused by defects are most likely to occur.  As a result you should:

  • Look for manufacturers’ warranties that cover materials and labor in the first three to five years after application on any grade of roofing shingle.
  • Carefully review the manufacturer’s warranty stipulations about proration and transferability.  Proration is the reduction of the manufacturer’s contribution to the homeowner for repairing or replacing defective shingles during the warranty period.  Select products carrying a warranty that does not prorate during the first three to five years after installation.  Also, make sure the warranty prorates on the current market cost of the replacement shingles (as opposed to the original cost of the defective shingles).
  • Examine the manufacturer’s stipulations on ventilation and warranty validation.  Shingle roof system failure as the result of inadequate ventilation may cause the shingle warranty to become invalid.
  • Note the contractor’s guarantee of performance.  Contractors’ guarantees are usually for one to five years on the average. Remember that the length of the contractor’s guarantee is less important than his ability or intent to stand behind his workmanship and to service a valid complaint in a reasonable time period.  This intent must be determined from referrals and references and his general reputation in the local business community.

Look for manufacturers’ warranties that cover materials and labor in the first three to five years after application on any grade of roofing shingle.  Some local building codes may have ordinances specifying a certain UL Class for your residential area.  Your contractor or local building codes officer can tell you what the requirements are for your particular area.

Selecting A Roofing Product Part 1

April 10, 2010

Selecting a roofing shingle is knowing whether your primary goal is function only, or function plus aesthetics.

Sometimes a homeowner who is looking to reroof for functional reasons may see a standard three-tab roofing shingle on a neighbor’s home and decide to go with the same product choice— and maybe even the same color.  But if appearance is a major factor in your reroof decision, then take the time to really look around.  You may want to visit a local distributor to obtain product literature and see the various designer shingle choices available.

The following some of the questions you can ask your roofing contractor when choosing a roofing shingle.

What’s the difference between an architectural, or designer, shingle and a standard shingle?

Since the early 1900’s, the three-tab or strip shingle was the standard composition shingle installed on single family residences.  These products come with 20, 25 and 30 year warranty coverage.

Color is about the only appearance differentiation in this class of shingle.  In 1965, CertainTeed

Corporation introduced the Hallmark Shangle, the first architectural or designer shingle on the market. The standard laminated “dragon-tooth” design followed that.  Other important innovations in architectural shingles include the Super Shangle and Super Shake styles.  Today, the architectural shingle class is running away with the market.

Warranties range up to 40 years and even lifetime.  Color is no longer the only choice to make.  The many textures, forms and designs of architectural shingles in the marketplace can result in a major aesthetic upgrade for your home.  Ask your roofing contractor to show you a good, better, and best selection of products.

Tips For Choosing a Roofing Contractor

April 10, 2010

Choosing a Roofing Contractor

One of the best ways to choose a roofing contractor is to speak with them over the phone or meet with them and ask them some questions.  To locate a roofing contractor to contact, you can ask friends and family for referrals or do a Google search as there are many great roofing directory sites that will provide a short list of roofers in your area.  It’s also worthwhile to check out the contractor’s own website as well.

Doing a little digging might seem time-consuming but what is even more time-consuming not to mention costly is to fix a botched roof job.  So how should you select a roofing contractor?  Tips for selecting a roofing contractor fall into three categories: the contractor’s qualifications, the contractor’s work, and the contractor’s past.  Read the tips below.

Qualifications

  • First, do not hire a roofing contractor who is not licensed. However, just because a contractor is licensed does not necessarily mean the contractor is a committed professional who will do excellent work.  You can tell more about a contractor’s commitment by seeing if the contractor is a member of a trade association and if the contractor has taken any continuing education training.  If the contractor says yes, call the trade association and ask to see certificates of the continuing education.
  • Make sure they have a permanent business. When selecting a contractor, you need to be confident that the contractor will be able to complete the work they promised to do. One of the best ways to have this confidence is to select a contractor who can financially commit to finishing your project.  The contractor should have a permanent phone number and address.  Visit their business to see if they have the equipment and employees to complete your project successfully.
  • Ask if they have insurance coverage and how much. Just because they have insurance, it might not be very much coverage.  Have the contractor show you a certificate of insurance.  Contractors can get a certificate of their insurance that shows coverage dates and policy limits from their insurance carrier.  Also ask if they have workers’ compensation coverage.  Because property owners can be sued for accidents that occur on their property, it is very important that all contractors have workers’ compensation insurance.

The Contractor’s Workmanship

  • All contractors also need to have a safety plan so ask your potential contractor to provide you with one.  Safety plans are important for making sure projects get completed and are required by the Occupational Safety and Health Administration (OSHA).
  • Find out how long the contractor’s warranty on work performed is.  A typical time period is one year or longer.  The length of the warranty doesn’t matter so much as whether the contractor plans to stand behind the warranty.  Good contractors often will work beyond a written contract.  Keep in mind that the manufacturer provides product warranties and often warranties are only valid if a contractor is “certified” to install the product.  Be sure to talk to your contractor about following manufacturer specifications that are necessary for product warranty.
  • The contractor should thoroughly discuss your home improvement project with you. Areas to talk about with your contractor include the color and type of products you want to use, how to get a permit if necessary, what the daily clean-up procedure is, and how the work will be paid for.

Past Performance and Customer Service

  • Find out how long the contractor has been in business.  Though a contractor in business for a year or two might do excellent work, it would be better to select a contractor who has been in business for at least five years.  Often the longer a contractor has been in business, the more experience they have, which often means more choices and better workmanship for your roof.
  • Ask to see pictures of the contractor’s work and for references from past customers.  Get this information on the contractor’s website or by calling previous customers and asking what they thought.
  • Many of the best contractors have had to handle complaints.  Complaints are not necessarily bad, but the way a contractor has handled them can be.  Ask the contractor how they have dealt with complaints in the past or call the Better Business Bureau to find out.

In addition to the above advice, another worthwhile tip for selecting a roofing contractor is to have three contractors you are considering submit three bids in writing.  Having three bids in writing is useful to compare prices and products the contractors will use to complete the project. If one bid is significantly higher or lower than the others, this could be a red flag.  Again, roofing directory sites can help streamline the process here, by putting you in contact with three roofing companies by filling out just one estimate request form.

Remember, what it all comes down to is what your instinct is telling you about the contractor. Even if the contractor manages to meet the above tips but something is telling you not to hire the contractor, don’t.  With a home improvement job as important as repairing or replacing a roof, you need to hire a roofing contractor whom you feel very good about the work getting done.