Follow these simple rules for getting your roofing projects just right.
|Surprisingly, one of the most common mistakes builders make on roofing projects is failing to follow installation instructions. Quizzing the crew on proper installation protocols and keeping current installation instructions on file with the jobsite superintendent are two ways builders can help avoid mistakes in the field.|
Through work with builders of all sizes in the National Housing Quality (NHQ) Certification Program, the NAHB Research Center has discovered several common mistakes and process omissions made on the jobsite that can jeopardize the quality and durability of typical, asphalt-shingle roof installations. Here are five areas builders should focus on to avoid those mistakes:
1. Follow all manufacturers’ installation instructions. Installation protocols and code requirements can vary significantly from one type, style or brand of shingle to another. For example, starter-course instructions, nailing-pattern requirements and roof-coverage area often vary from product to product. Unfortunately, instructions often get overlooked or discarded altogether during the construction process. Failing to follow instructions can lead to durability problems and can possibly void the manufacturer’s warranty, leaving the builder bearing the full cost of any needed repair or replacement. Here are three simple ways builders can reinforce the importance of following installation instructions:
2. Create a comprehensive job plan. A builder’s goal with any element of a job should always be to do it right the first time to avoid costly delays. The key to getting it right is creating a comprehensive job plan for every type of work on the site. Roofing is no exception. Here are three tips for creating an effective roofing job plan:
3. Get the fastening details right. Builders often specify the type and style of shingle for the roof, but they rarely choose the type and gauge of fasteners for those shingles. Using the wrong fasteners can lead to wind damage and result in a red tag by the code inspector.
Builders often specify the type and style of shingle for the roof, but they rarely choose
the type and gauge of fasteners for those shingles. Using the wrong fasteners can lead
to wind damage and result in a red tag by the code inspector.
The type of fastener required for the job is called out in the manufacturer’s installation instructions, as well as in the local building code. If you have a personal preference for either nails or staples, make sure that detail is included on the approved plans and specifications for a given project, as well as in the roofer’s scope of work. If staples are to be substituted for roofing nails, make sure the acceptable wire gauge and staple length are clearly stated, as well.
4. Adjust nail guns for the job. As the builder, you may not own and use nail guns on the jobsite, but it’s your responsibility to make sure they are adjusted to the proper settings to provide adequate, consistent fastener penetration. Too little pressure leaves the crown of the nail or staple too high, creating a bulge in the profile of the shingle. Too much pressure and the nail or staple can crush the shingle or even be driven through it.
If a nail gun or automatic stapler is to be used, make sure the air pressure is correct. Also, because air pressure can change over the course of a day, the compressor should be checked periodically to ensure air pressure remains within an acceptable range. Ask your trade contractor to document all air pressure checks and adjustments during the course of the day.
5. Conduct a personal inspection of the completed work. An inspection from both the roof level and ground will ensure that the quality of workmanship and aesthetic details are what you expect. As part of the inspection, you should:
Document all required corrections and agree with the roofing contractor on when a follow-up inspection can be scheduled. Don’t assume the corrections will be made; always re-inspect. Document all inspections and make sure you and the roofer sign off on the final report.
Specific scopes of work and inspection checklists are two key elements of a documented quality management system adopted and implemented by quality-minded builders across the country. Check out the NAHB Research Center’s Web site  for more information on implementing quality management systems for both builders and trade partners.
Created in 1964, the NAHB Research Center  is a full-service product commercialization company that strives to make housing more durable, affordable and efficient. The Research Center provides public and private clients with an unrivaled depth of understanding of the housing industry and access to its business leaders.