Black Tar On Back On Roof Shingles

What is the purpose of the glue strip on asphalt roof shingles.

Black tar on back on roof shingles. The preferred method though is to either replace the shingles that are leaking by removing the damaged shingles and replacing them and the roofing felt underneath or by lifting the row of shingles just above the damaged point and adding new. The black streaks running down roofs are actually a hardy algae called gloeocapsa magma. The algae feed on the limestone in shingles. If you have a simple leak in your roof and know exactly where it is then you can apply roofing tar over the affected area to create an effective patch.

While you can apply roofing tar at lower temperatures it will not properly set until it reaches 70 degrees. Sometimes the tar accidentally gets on objects or fabrics and the longer it sits there the harder it dries often making it difficult or challenging to remove it. After application press the tab down firmly to start the bond. The shiny black strips form the glue line on the shingle.

The most common type is known as gloeocapsa magma also known as blue green algae. When to tar a roof. As the blue green algae accumulate they develop a dark hardened outer coating which results in the black stains you see. Although these dark spots and ugly black streaks on your roof may look like dirt mildew soot or mold what they really are is algae.

The ideal temperature is 70 degrees f. When applying roofing tar make sure that you have at least a few consecutive days of sunshine without rain or snow so that the tar has time to cure. While you may have an isolated incident that lead to a broken or missing shingle sometimes this can be a sign that you have other damaged or weakened areas elsewhere on your roof. Our photo left shows a typical 3 tab asphalt roof shingle this one is made by gaf.

Simply slapping some tar on there instead of having a professional come out to assess could mean that you re leaving other damaged areas open to the elements as well. Each spot should be approximately the size of a quarter and placed 1 to 2 from each end of the tab and near the bottom. Prevent shingle damage from wind uplift. Laminated shingles require 4 spots of cement per shingle.