Architectural Versus Three-Tab, and Why We Rarely Install Three-Tab
Three-tab shingles are a single flat layer with cutouts that create the tab pattern. They were the standard for decades, they are the cheapest option, and they are what sits on most North Atlanta homes built before the early 2000s. They typically carry a 60 mph wind rating and a 20 to 25 year nominal life that Georgia heat tends to shorten.
Architectural shingles, also called dimensional or laminate shingles, bond two or more layers together. That construction gives them roughly double the weight per square, a wind rating commonly rated to 110 or 130 mph when installed to manufacturer specification, and a limited lifetime warranty. They also read as a far better roof from the street, because the varied thickness casts a shadow line that flat three-tab cannot.
The price difference between the two, spread across a roof that has to last twenty-five years, is small enough that we install architectural on nearly every home. The exception is a genuine repair match on an existing three-tab roof, where the goal is to blend into what is already there.
What Georgia Weather Actually Does to a Shingle Roof
Three things age shingles here, and each has a specific countermeasure. Heat is the first. A dark roof deck in a metro Atlanta July runs far hotter than the air temperature, and sustained heat drives the volatile oils out of the asphalt, which is what leads to the curling and cracking you see on older south-facing and west-facing slopes. The countermeasure is ventilation rather than the shingle itself: balanced soffit intake and ridge exhaust move that heat out of the attic instead of letting it cook the roof from below.
Humidity and shade are the second, and they produce the black streaking that homeowners across Roswell, Marietta, and the Chattahoochee corridor recognize immediately. Those streaks are Gloeocapsa magma, an algae that thrives on the limestone filler in shingles under damp, shaded conditions. It is cosmetic before it is structural, but it holds moisture against the roof. We install algae-resistant shingles containing copper granules as standard, and we can add zinc or copper strips at the ridge on heavily canopied lots.
Hail and wind are the third. Cherokee, Cobb, and North Fulton take damaging hail most springs. Hail rarely punches through an architectural shingle, but it bruises the mat underneath, which shortens the roof’s life invisibly. Wind failures almost always begin at an edge or a ridge rather than in the middle of a slope, which is why the drip edge, starter course, and ridge cap details matter far more than their share of the cost suggests.
The Parts of a Shingle Roof That Are Not the Shingles
When a shingle roof leaks, the shingles are usually not the cause. Water gets in at the transitions: valleys where two slopes meet, step flashing where the roof meets a wall, counter flashing at the chimney, and the rubber boots around plumbing vents. Boots in particular are a known failure point, because the rubber hardens and splits in our UV exposure long before the surrounding shingles are worn out.
Underneath the shingles, we install a synthetic underlayment rather than traditional felt. Synthetic holds up far better to heat and to foot traffic, and it does not wrinkle when it gets wet during installation the way felt does. In the valleys and around every penetration we install a self-adhered ice-and-water membrane, which seals around the nails driven through it.
At the edges, a proper starter course along the eaves and rakes is what gives the first row of shingles something to bond to. Skipping or improvising the starter course is one of the most common shortcuts in this market and one of the most common causes of wind loss along an edge. It is worth asking any bidder whether a manufacturer starter strip is in their scope.
Choosing a Color, and Living With It for Twenty-Five Years
Shingle color is the most visible decision you will make and the hardest to judge from a three-inch sample. Colors read considerably lighter across a full roof than they do in your hand, and they change substantially between overcast and direct sun. We bring full-size samples and will show you completed roofs in your area in the same color, which is far more useful than a brochure.
Lighter and more reflective colors absorb less heat, which helps a little in our summers, though ventilation does far more for attic temperature than shingle color does. If you are in an HOA neighborhood in Johns Creek, Woodstock, Milton, or Holly Springs, there is very likely an approved palette, and we will help you select a compliant color and supply the product data your architectural review committee needs before we order anything.
Shingle Repair, and When It Is the Right Answer
Not every shingle problem is a roof problem. Wind-lifted shingles along one edge, a handful of shingles lost off a ridge, a split boot, or a length of failed step flashing are all straightforward repairs, and on a roof with life left in it a repair is the correct and honest answer.
The real constraint on shingle repair is matching. Shingle lines are discontinued, and granule colors shift between production runs, so a repair on a fifteen-year-old roof will rarely be invisible. We keep the match as close as available product allows and will tell you upfront how noticeable it is likely to be, so you can decide whether a visible patch on a front-facing slope is acceptable to you.