Wind Zipper Pattern Roofing

An unbonded pattern of shingle tabs in a racked installation is commonly referred to as zippering chalk lines in figure 6 show the nonbonded shingle portions.

Wind zipper pattern roofing.

Some problems stem from environmental temperatures. When wind speed is 100 mph or greater block panel edges perpendicular to gable end wall framing members in the first two bays of. The featured self sealing asphalt strip provides added wind resistance. Joints of underlying shingles.

These unbonded overlaps will not vary in direction or increase decrease in areas of the roof where wind uplift would be greater less. During your roof assessment have you identified displaced shingles on the roof. Many times after the wind leaves these zippering impressions the shingles will reseal however they reseal at a severely diminished value approximately a 90 diminished uplift resistance value. We can t blame all roofing repair on the wind.

The shingles are made with a double layer of fiberglass mat for strength and weather resistant construction. It was found that three tab asphalt shingles did not. Are these displaced shin gles the result of wind forces or from slippage. The dirt and debris that will inevitably get embedded into the exposed mastic cannot be cleaned thoroughly enough to ever be reusable.

Image 4 image 3. The height of the roof and exposure and risk categories are factors that are used to convert design wind speed to an uplift pressure. All heritage series roof covering have a random cut saw tooth design to prevent the unsightly zipper pattern. Photos and text guide diagnosis of asphalt roof failures how to identify and explain roof shingle failures obtain claims assistance contribute failure information at this website.

Wind loads are based on the design wind speed which is based on the geographic location of the building height of the roof exposure category roof type enclosure classification and risk category. Irc table r602 3 1 footnote f g. Are there adjoining shingles that have. Where creasing bending flipping tearing punctures dislodging or nail head pull through occur on roof slopes in multiple directions the pattern indicates that the damage may be a result of multiple events some of which may be excessive winds.

When wind speed is 110 mph or greater and when median roof height is between 25 and 35 feet use 8d ring shank nails 0 135 x 2 1 2 inches within 48 inches of gable end walls. Wind damage to asphalt shingles installed in the racking or straight up pattern after hurricane frances. How to recognize asphalt roof shingle or other roof type damage by wind hurricane storms and how to get. The following is a list of questions to consider when you as the inspector are assessing a shingle roof for reported wind damage.