Metal Roofing

How a Metal Roof Goes On: Deck, Underlayment, Panels

Metal roofing is the work of covering a prepared substrate with metal panels so water sheds off the eave and never reaches the decking. The whole job is really waterproofing the valley and weatherproofing every penetration. Here is the order we follow.

1. A roof inspection checks the roof deck, truss and rafter spacing, and joist and ridge beam condition before anyone orders a panel.
2. Failed asphalt shingle, wood shake, or cedar shake comes off in a full tear-off, and we load the debris into a dumpster the same day.
3. Soft plywood or OSB sheathing is replaced and re-nailed, because a fastener cannot hold in decking that has already begun to rot.
4. A synthetic underlayment goes over the sheathing, with ice-and-water shield along the valley and the eave.
5. Battens or a counterbatten grid lift each metal panel off the deck so condensation drains and air moves underneath.
6. A standing-seam panel is locked down with concealed clips, while a corrugated panel is screwed through the metal into the purlin.
7. Ridge cap, drip edge, and hip flashing close the roof, and step flashing, counter-flashing, chimney flashing, and pipe flashing seal the penetrations.
8. Gutter and downspout work finishes the drainage path, then we sweep the yard with a roofing shovel and a magnet for stray nails.
9. Our crew carries a roofing square, pry bar, nail gun, and air compressor, sets a scaffold where the pitch allows, and ties off a fall-protection anchor before anyone steps onto a panel.

Metal Panel Options and Why Gauge and Finish Matter

Standing-seam steel is the premium route for a homeowner staying put: concealed fasteners, no exposed screw heads, and a service life measured in decades. Exposed-fastener panels cost less up front and suit a patio cover or shop roof.

• A standing-seam panel moves with temperature because the clip lets the metal slide instead of tearing at the fastener.
• Exposed-fastener panels depend on a gasketed screw at every purlin, and one overdriven screw becomes a leak nobody sees for months.
• Stone-coated steel copies clay tile, concrete tile, or slate without the weight a truss may not be rated to carry.
• Aluminum sheds corrosion on a rooftop near pool equipment, while steel holds up better against hail.
• PVDF and SMP finishes hold color under Phoenix UV when the coating goes on at the specified dry film thickness.
• McElroy Metal, ATAS, and Decra publish profile and gauge charts we weigh before recommending a panel.

What a Roof Inspection Finds on a Phoenix Rooftop

Heat and UV do the damage here, not freeze-thaw cycles. We set a ladder, tie off a safety harness, and walk the full roofline, including the parts you cannot see from the driveway.

• Granule loss and end-of-life wear on an architectural shingle or three-tab shingle mean the mat is exposed.
• Seams that peel, flake, or spall on a modified bitumen or built-up roof let water wick into the decking below.
• A sagging ridge or a settled rafter usually traces to wet wood, not a bad panel, so the repair starts under the surface.
• Rusted fasteners, loose screws, and cracked sealant, caulk, or adhesive at a pipe boot or vent boot are the leak points we find most.
• Roofing felt or tar paper that has dried to dust no longer sheds water, and old mastic or roof cement patches have already cracked.
• Ponding water on a TPO, EPDM, or PVC membrane usually means the slope failed, not the membrane.
• Fascia, soffit, rake, and the overhang above a patio canopy or awning all get checked, since rot shows up there before the roof fails.
• On a low-slope section behind a parapet, we check the coping and the scupper that drains it, because both clog with monsoon dust.
• The roofer who inspects your home writes the scope, so nothing gets lost between the estimate and the crew.

Desert Conditions That Change the Work

Phoenix averages about 111 days a year at or above 100 F, and 21 of those reach 110 F. That heat oxidizes asphalt, bakes tile underlayment, and stresses every panel on the roof.

• Thermal movement means clips and fasteners have to let the panel expand instead of locking it in place.
• Insulation and ventilation work as a pair: a ridge vent, soffit vent, or attic fan keeps the attic from cooking the deck from below.
• Monsoon hail bruises shingle, dents soft metal, and can puncture a coating that has thinned.
• Dust collects in a valley or against a parapet and holds moisture on the substrate long after the rain stops.

Timelines, Cost Drivers, and What We Will Not Sell You

A residential metal roof on a single-story ranch typically runs two to four days once the panel is on site. Fabrication lead time and the permit set the real start date, not the roof estimate.

• Roof pitch and total roofing squares move labor cost faster than any material choice.
• A tear-off costs more than an overlay, but an overlay hides rot and sheathing damage you pay for later.
• A dormer, skylight, chimney, or mansard and gambrel section adds flashing detail and crew hours.
• Maricopa County building code may require a specific fastening schedule, a permit, and an inspection sign-off.
• We skip the snow guard, because Phoenix does not need one, and we do not add a vapor barrier where it would trap attic moisture.
• If a repair coat, an elastic coating, or a torch-applied modified bitumen section buys you five more years, we say so instead of pushing a full roof replacement.

Call Phoenix Roof Master at 6025330488 for a free roof estimate, a written scope, and a straight answer on whether your roof needs a metal roofing install, a repair, or a recoat.