Do you need to replace your home's current roof, and you're thinking of using three tab asphalt shingles to get the job done? If so, it will help to know what to expect during the installation process. A company like KRG Roofing is experienced with this technique.  

Chalk Lines Will Be Made

It is very common for chalk lines to be placed on the roof to help align each row of shingles. Experienced roofers may skip marking every other row of shingles to speed up the chalking process. Measurements are made on each side of the roof at the starting position of each row, and then a string with chalk on will be snapped across the surface. 

Starter Shingles Will Be Installed

Your new roof is going to require a row of starter shingles along the bottom edge of the roof. However, there are two ways that this can be done. A special type of starter shingle can be purchased for this exact purpose, or regular three tab shingles can be used with the tabs cut off of them. Either technique is fine for the starter row. Once installed, the starter shingles are going to slightly hang over the edge of the roof.

Staggering Is Necessary To Offset The Pattern

Each row of shingles will be slightly staggered across each row so that the shingles don't line up at the exact same spot. You'll notice that the first row starts with a full shingle lined up to the edge of the roof. Each additional row requires trimming some of the shingle material off that first shingle that starts the row. 

The amount that is trimmed should be about half the width of one of the tabs on the shingles. There will eventually be six rows of shingles that are staggered up your roof, with the sixth row only being half of one tab worth of shingle material. The seventh row then starts with a full shingle. This ensures that the seams are spread out evenly across the roof.

Nails Are Inserted Below The Glue Line

You'll notice a line that goes across each shingle horizontally. This is actually a line of adhesive that is used to attach to the row of shingles above it. The row of nails is put right below this glue line, with nails to the left and right of each tab of shingle material. 

Using this process, the roofing contractor will eventually cover your entire roof with new shingle material. While the process may seem complicated, you'll be surprised at how fast your new roof comes together when it's done by a professional.