Tempe Expert Roofing: Tile, Foam & Shingle Roof Replacement & Repair

A full roof replacement removes every existing layer down to the roof deck, which the code requires for a replacement. With the deck bare, the roofer can find soft or delaminated sheathing and replace it before new underlayment, drip edge, wall and penetration flashings, and the new covering go on.

Whether you need a permit depends on what changes. Tempe exempts a replacement roof covering from a building permit when the new covering's classification is equal to or better than the old one and it doesn't load the framing beyond its design capacity. Replacing sheathing, or any other part of the roof assembly, does need a permit. Going from shingle to tile adds weight, and that is the case the rule is written for, so it gets checked.

See roof replacement in Tempe.

Think of the tile as a sunshade and the underlayment beneath it as the raincoat. When the underlayment dries out and cracks, a roof with good-looking tile can still leak.

An underlayment replacement is a lift-and-relay job. The tiles come off and are stacked on the roof, the old underlayment and battens are torn off, and the deck is checked. New underlayment, battens and flashings at valleys, walls and pipes go down, then the tiles go back. The code allows sound clay or cement tile to be reinstalled but not damaged, cracked or broken tile, and rusted or damaged flashings, vents and edgings have to be replaced.

Slope matters here. On tile roofs between 2½:12 and 4:12, the code requires two layers of underlayment. Ask the estimate to name the underlayment product and say whether it's one layer or two.

See tile roof underlayment replacement.

Tile roof repair covers the problems that don't need the whole roof lifted: cracked or slipped field tiles, loose hip and ridge tiles, rusted or clogged valley metal, and failed flashing around vents, pipes and skylights. Concrete and clay tile both come in S-shaped and flat profiles, and a repair only looks right when the replacement tile matches the profile and color.

Fastening counts too. The code requires at least one fastener on every perimeter tile, and tiles weighing under 9 pounds per square foot installed need at least one fastener per tile at any slope.

See tile roof repair.

Spray polyurethane foam (SPF) goes on as a liquid and expands into one seamless, insulating layer with no laps or seams to open up. That's why it suits the flat and low-slope sections behind parapet walls that you see across Tempe. The code sets a minimum design slope of ¼ inch per foot for drainage, and it requires a liquid-applied protective coating within 2 to 72 hours after the foam is sprayed.

Foam roof problems to look for: ponding at low spots, blisters, bird pecking, coating worn thin enough to expose the foam to the sun, and cracking where the foam meets parapet caps and scuppers.

See foam roofing and foam roof repair.

On a foam roof, the coating is the part that wears out. The foam lasts as long as the coating keeps sunlight off it. The code lists three protective coating types for foam: acrylic (ASTM D6083), silicone (ASTM D6694) and moisture-cured polyurethane (ASTM D6947).

Our view: pick the product for the roof, not the price per bucket.

A recoat doesn't require a tear-off. The code allows a new coating over an existing coating, foam, built-up, modified bitumen, single-ply or metal roof, as long as the roof isn't water-soaked or deteriorated. The crew washes the roof, cuts out and patches damaged foam, primes where the manufacturer calls for it, and applies the coating at the thickness the manufacturer specifies. Ask for that thickness and the recoat interval in writing.

See roof coating.

Asphalt shingles need a slope of at least 2:12, and between 2:12 and 4:12 the code requires two layers of underlayment. Each strip shingle gets at least four fasteners, and shingles have to be tested for wind to ASTM D7158 with a classification that matches the design wind speed.

Attic ventilation belongs in any shingle quote.

See shingle roofing.

Metal roofing comes in two broad kinds. Standing-seam systems, with raised seams and hidden fasteners, can go on slopes as low as ¼ inch per foot. Lapped, exposed-fastener panels need 3:12 without lap sealant, or ½:12 with sealant applied to the manufacturer's instructions. A light, reflective finish helps keep attic heat down.

See metal roofing.

Foam isn't the only flat roof option. Modified bitumen, built-up roofing (BUR) and TPO single-ply membrane all need a design slope of at least ¼ inch per foot for drainage (coal-tar built-up roofs can go to ⅛ inch). Unless the roof sheds water over its edges, the code wants a drain at each low point. On a reroof, the existing slope can stay as long as the roof drains positively.

Check the edges first: parapet caps, scuppers, and the flashing around AC stands and pipes.

See flat roof repair.

On a tile roof, water can travel along the underlayment and battens before it drips, so the stain on your ceiling may be several feet from where the water gets in. Leak repair starts with tracing the path back to the entry point: a valley, a wall flashing, a pipe boot, a skylight curb, or on flat roofs a parapet cap or an AC stand.

A tarp or sealant patch buys time. The permanent fix replaces whatever failed, whether that's a tile, a flashing, a pipe boot or a section of underlayment.

See roof leak repair and roof repair.

A roof inspection should leave you with photos and written findings: tile condition, underlayment showing through broken tiles, flashing, foam coating wear, and drains and scuppers. Book one before monsoon season, after a big storm, and before buying or selling a home.

See roof inspection.