Can new shingles go over old ones?

Sometimes. The code doesn't allow a recover over a roof that is water-soaked or deteriorated or that already has two or more layers. A full replacement removes the old layers down to the deck and lets the roofer check and repair the sheathing.

What type of shingle is best?

One with an ASTM D7158 wind classification that matches the design wind speed for your house, installed with the fasteners and underlayment the code and the manufacturer require. Architectural shingles give a thicker, textured look.

What are the downsides of a shingle roof?

Sun and heat age asphalt shingles, which is why attic ventilation matters. Shingles also need a slope of at least 2:12, so they can't go on flat or very low-pitched sections.

Shingle Roofing in Tempe, AZ

Shingle Roofing Services

Asphalt shingles need a slope of at least 2:12. Each service below follows the code rules for that roof.

Roofer nailing dimensional architectural asphalt shingles on a sloped roof in bright Arizona sun

Architectural Shingle Installation

Architectural (dimensional) shingles are laminated for a thicker, textured look. An install lays underlayment first, two layers on slopes from 2:12 to 4:12, then shingles with at least four fasteners per strip. The shingle bundle has to carry an ASTM D7158 wind classification that matches the design wind speed for the house. Ask for the product line and its classification on the estimate.

Shingle Roof Repair

Repair replaces lifted, cracked, torn or missing shingles, matching the color and the wind rating of the roof. The roofer checks the underlayment and deck where shingles come off, and reseals tabs that have lost their bond.

Metal drip edge and step flashing along an eave and sidewall of an asphalt shingle roof

Drip Edge, Valleys and Sidewall Flashing

The code sets the details that keep water out at the edges:

Drip edge at eaves and rakes, lapped at least 2 inches, extending at least ¼ inch below the sheathing and 2 inches up the deck, fastened at no more than 12 inches on center. Underlayment goes over it at the eaves and under it at the rakes.
Valleys lined before shingles go on. An open metal valley lining has to be at least 24 inches wide.
Sidewall flashing, continuous or step flashing at least 4 inches high and 4 inches wide, directing water away from the wall.

Attic Ventilation

Balanced intake and exhaust vents move hot air out of the attic. That keeps heat from building up under the deck, protecting shingles and underlayment from below. A shingle quote should say what ventilation the roof has and whether it will change.

Roller spreading white elastomeric coating over weathered spray foam on a flat roof behind a stucco parapet

Why Tempe homeowners call Tempe Expert Roofing

Free, no-obligation roof estimates
Written scope: tear-off, underlayment, flashing, coating
Photos of every finding on your roof
Permit and code questions answered up front
One call, one local roofer

What Affects the Cost of a Shingle Roof

Roof area, pitch and the number of stories.
Layers torn off and deck repair.
Shingle line and its wind classification.
Underlayment layers, valleys, drip edge and flashing.
Ventilation changes.

Code Basics for Shingle Roofs in Tempe

Tempe adopted the 2024 International Codes effective July 1, 2026, with a transition through December 31, 2026 when either the 2018 or 2024 codes can be used. The shingle rules on this page come from the 2024 International Residential Code:

Minimum slope 2:12, with two layers of underlayment from 2:12 to 4:12.
Shingles meeting ASTM D3462 and labeled with an ASTM D7158 wind classification.
At least four fasteners per strip shingle.
Drip edge at every eave and rake.

A replacement covering of the same or better classification that doesn't add load is exempt from a Tempe building permit. Replacing sheathing needs one. See roof replacement for the full process.