Asphalt Shingle Grades and the Layer Rule
Asphalt shingles all start the same way: a fiberglass mat soaked in asphalt and faced with mineral granules. What separates the grades is thickness, the number of layers laminated together, and the ratings printed on the wrapper. The installed prices below are HomeGuide's 2026 national ranges per square (100 square feet of roof).
Three-Tab Shingles
A three-tab shingle is one flat layer with two slots cut into its lower edge, so each strip reads as three equal tabs. Laid up, the roof looks like a grid. HomeGuide puts three-tab at $200 to $500 per square installed with a 15 to 20 year life, the cheapest and shortest-lived option.
On wind, the floor is set by code. Michigan's residential code ties shingle wind ratings to the design wind speed, and at Ann Arbor's 90 mph that means ASTM D3161 Class A, D or F, or ASTM D7158 Class D, G or H. Class A is a 60 mph fan test. A three-tab carrying that label meets the code here, and it's still the lowest rating that does.
Three-tab still makes sense on a garage, a rental you plan to re-roof in a decade, or a small section that has to match an older three-tab roof.
Architectural (Dimensional) Shingles
Architectural shingles are two layers bonded together, with the bottom layer showing through irregular cutouts in the top one. That's what puts the shadow lines in a roof. HomeGuide prices them at $400 to $600 per square installed, with a 20 to 30 year life. For the money, they're the grade we'd point most Ann Arbor owners toward.
The extra thickness helps in wind and gives the nails more to hold. The code minimum is four fasteners per strip shingle, driven at least 3/4 inch into the deck or through it.
Designer and Luxury Shingles
Designer (or luxury) shingles are thicker, multi-layer laminates cut to imitate natural slate or wood shake, often with deeper shadow bands and larger tabs. HomeGuide has them at $500 to $700 per square installed, with a 25 to 40 year life.
They're the usual answer when an owner wants the look of a slate or cedar roof without its price. In one of Ann Arbor's historic districts, though, an asphalt "slate" replacing real slate isn't something city staff can sign off on alone. That route is covered on our slate roof repair page.
Class 4 Impact-Resistant Shingles
Impact ratings come from UL 2218. A shingle earns Class 4, the top rating, when it survives a 2-inch steel ball dropped from 20 feet without cracking. Class 3 uses a 1.75-inch ball from 17 feet. GAF notes that Class 3 and 4 products "may even qualify for insurance discounts", and also that it makes no warranty on how they hold up against real hail. Ask your insurer before you pay extra for the rating.
Wind ratings sit alongside it. Class F under ASTM D3161 is the top fan-test class: the shingle held at 110 mph. ASTM D7158 Class H covers basic wind speeds up to 150 mph. Premium architectural lines commonly list D3161 Class F, D7158 and a UL 790 Class A fire rating on the same spec sheet. How often hail actually hits Washtenaw County is on our storm damage roof repair page.
Re-Cover or Tear-Off: the Layer Limit
Michigan follows the 2015 Michigan Residential Code. Section R908.3.1.1 bars a new roof covering over an existing one in three cases:
- the roof already has two or more layers of any kind of covering;
- the existing roof is water-soaked or has deteriorated so it can't serve as a base;
- the existing covering is slate, clay, cement or asbestos-cement tile.
So a roof with one sound layer of shingles can legally take a second. HomeGuide lists what that saves you and what it costs: removal runs $1 to $3 per square foot, but shingling over adds weight, shortens the new roof's life and keeps the contractor from seeing the deck. The code also wants rusted or damaged flashings, edgings and vents replaced either way.
Our view: on most Ann Arbor houses a tear-off is worth it. A re-cover leaves the eave without a fresh ice barrier on the deck (the code's rule is explained on our ice dam removal page), and soft boards stay hidden. What a full tear-off includes, step by step, is on the roof replacement page.
Why Ann Arbor homeowners call Ann Arbor Roofing Co.
- Written estimate, free of charge
- Shingle line, underlayment and ice barrier named in the price
- Deck repair priced per sheet before the tear-off
- One independent local roofer per request, not a call list
- No fee to the homeowner for the referral
How Long Does an Asphalt Shingle Roof Last in Ann Arbor?
Plan on about 20 years for an average asphalt roof here, more for architectural and designer grades. The NAHB life-expectancy study put asphalt at about 20 years, and HomeGuide's 2026 range is 15 to 30. Our view: freeze-thaw cycles, deep snow and summer hail push Ann Arbor roofs toward the lower half of those ranges.
The signs that a shingle roof is near the end show up from the ground and in the gutters:
- granules collecting in the gutters or at downspout outlets, with bare dark patches on the shingles;
- tabs curling at the corners or cupping in the middle;
- cracked or missing tabs, often worst on the slopes that get the most afternoon sun;
- repairs that keep moving from one spot to the next.
One leak around a vent pipe or chimney isn't a reason to re-roof. A roof that shows all four of the signs above usually is. A roof flatter than the code's minimum pitch for shingles belongs on our flat roofing page instead.
What a Shingle Estimate Should Spell Out
A shingle quote is easy to compare only if each one names the same things. Ask for these in writing:
- 1
The shingle line and grade
, not just "architectural". The manufacturer's name and product line let you look up its ratings yourself. - 2
The wind class
on the wrapper (D3161 or D7158) and, if you're paying for it, the UL 2218 impact class. - 3
Tear-off or re-cover
, and how many layers are coming off. Removal is priced by layer. - 4
Fasteners
: at least four per strip, more if the manufacturer's instructions call for it on your roof. - 5
Starter strip, hip and ridge caps
, and whether they come from the same product family as the field shingles. - 6
A price per sheet
for deck boards that turn out to be rotten once the old roof is off.
Two estimates that both say "30-year architectural shingles, tear-off included" can still be a grade and a layer apart. If you're also weighing steel, compare against standing seam metal roofing, which costs more up front and lasts longer.
See roof replacement in Ann Arbor. See storm damage roof repair in Ann Arbor.