Why it is important and the problems it can create.
A lot has changed in the roofing industry over the past 30 years. Shingles and the installation process have modernized along the way. Most asphalt shingles are now produced with an inorganic fiberglass core compared to the shingles my dad installed years ago that consisted of an organic core that was similar to a rag. The quality of the asphalt and the additives put in the shingles have gotten much better. Todays shingles can withstand greater temperature swings and are more flexible. They even have mildew resistant features that keep those black streaks from forming for many many years. As for installation, we now have modern equipment like ladder lifts and nail guns which have helped increase production. But there is one thing that has not changed one bit and that is the shingle nailing pattern.
Nails in Butt Joints
Where a nail is driven into a shingle is vital. A nail driven too high and the shingle may slide out or blow off in moderate winds. A nail driven too low may be exposed. It is also very important to ensure the nail pattern is such that no nails are driven where the shingles in the next row butt together. As you can see in the video below, this is a common problem we find on customers roofs. In most cases the roof is several years old before there is any visible sign of a problem. Typically the roof will develop a leak that alerts the home owner there is a problem. Only then it it discovered that the cause of the leak is due to improper shingle nailing pattern. Any nail driven into a shingle directly in line with a but joint will leak. It is only a matter of time.
Nails driven below the nail line on a roof shingle are commonly referred to as a “low nail” or a “shiner”. Call it what you will, this nailing mistake is never good. When a nail is driven low enough below the nail line, it is left exposed. Meaning, the next row of shingles does not cover the nail. These exposed nails are not protected and will leak at some point. Exposed nails should be taken care of right away. This is one of many reasons why a post roof install inspection is very important. A quick inspection of the roof after it is installed is the best way to spot low nails.
Nails driven above the nail line on a roof shingle are known as a “high nail”. This issue is especially critical with laminate shingles. A nail driven too far above the nail line will miss the laminate and therefore not secure the shingle properly. High nails often lead to shingles sliding out or falling off the roof and are especially susceptible to blow off even in minor wind events.
Hiring a Professional
A professionally installed roof system is much more than just how it is nailed. The materials used are just as important as the people installing them. Local, reputable roofing contractors like McToolman will always use the highest grade materials and trained installers. Our expert team of residential roofers have been providing outstanding service to customers for many years. We will provide the best service at the most affordable price. Our customers are happy to see us! We are proud to deliver a high-quality product within the agreed timeframe and at a fair price. You can be sure that you are getting great value when you hire us.