Aluminum Roofing Systems
Aluminum Standing Seam Panels
Aluminum standing seam goes on like steel standing seam: long pans, raised seams, hidden clips. It's just less common. In a JLC Q&A, a metal roofing manufacturer estimated that about 85% of standing seam is made from galvanized or Galvalume steel, with aluminum around 5%.
Thickness is the first thing to read on the quote. The Michigan Residential Code sets a 0.024-inch minimum for roll-formed aluminum panels (ASTM B209). The same JLC answer gives .032 to .050 inch as typical for aluminum standing seam, with the heavier panels strong enough to span purlins without a deck, against roughly .015 to .030 inch for steel.
Aluminum also grows and shrinks more than steel as it heats and cools. Englert, a panel maker, says that calls for floating clips on long runs to prevent warping and oil canning. On a long eave-to-ridge run, ask whether the clips are fixed or floating. Clip fastening and oil canning in general are covered on our standing seam metal roofing page.
The premium over steel varies by source. JLC puts it at about 10 to 20% over Galvalume or galvanized standing seam, and Englert at 20 to 35% in many markets.
Aluminum Shingles and Shakes
Stamped aluminum shingles are small interlocking pieces pressed to look like shake, slate or a dimensional shingle. The code minimum for press-formed aluminum shingles is 0.019 inch, thinner than the 0.024-inch minimum for panels.
Each piece interlocks with the ones beside and above it and is fastened through a hidden flange, so the fasteners end up covered.
The main reason to pick aluminum shingles over steel ones is weight. Western States Metal Roofing puts aluminum at roughly a third of the weight of steel, which counts on an older frame or when the shingles go over an existing roof. Englert adds that embossed or textured finishes hide small imperfections better than a smooth face.
They follow the same slope rule as any metal shingle. The minimum pitch and the code section are on our metal shingle roofing page.
Aluminum for Overlays and Light Framing
On a house, aluminum is most useful where weight and rust both matter:
- Over an existing roof. A lighter panel puts less new load on rafters that already carry an old roof. Whether an overlay is allowed at all is a code question, covered on our metal roof over shingles page.
- Screened porches, patio covers and sunrooms. Light framing and often a low pitch. Aluminum won't rust at a scratch or cut edge, which JLC counts as one of its main advantages.
- Panels over purlins. The code lets metal panels sit on spaced supports only when the panel is designed for it. That means the heavier aluminum panels JLC describes, not the thin stock.
Aluminum next to copper is a problem. Keep them apart, and don't let copper flashing or a copper roof drain onto aluminum. The details are on our copper roofing page.
Why Livonia homeowners call Livonia Metal Roofing
- Estimate in writing, at no cost
- Gauge, panel profile and paint finish named in the quote
- Re-roof permit listed in the written scope
- One independent local metal roofer per request
- Homeowners pay nothing for the referral
Aluminum or Steel on a Livonia House
Aluminum's best-known advantage is salt. Englert and Western States both recommend it near the ocean, where salt spray eats through steel's coating. Livonia is a long way from the coast. Englert's advice for inland, dry regions is that coated steel is usually the better value, and steel dents less in hail.
So our view is that most whole-house roofs here are better off in painted Galvalume steel, and aluminum earns its premium in narrower cases:
- A porch, sunroom or addition roof over light framing.
- An overlay where every pound counts.
- An owner who wants zero rust risk at cut edges and scratches, and accepts the dents.
Englert does point out one upside to aluminum dents: they don't rust. A deep hit on steel can break the coating and start corrosion if nobody seals it.
JLC also notes aluminum gives off heat faster than steel, which can make it the more energy-efficient choice in warm climates. That's a Sun Belt advantage. Here, as our homepage comparison explains, attic insulation does more for the energy bill than the choice of metal.
How an Aluminum Roof Goes On
The sequence looks like any metal roof, with a few aluminum-specific steps:
- 1
Deck and underlayment
Solid sheathing for standing seam and shingles, with the ice barrier at the eaves and synthetic underlayment above it. The rules are on our underlayment and ventilation page. - 2
Trim first
Eave and rake trim in aluminum, so the panels never sit on a dissimilar metal. - 3
Clips and panels
Panels are cut to the slope's length, and floating clips go on wherever the run is long enough for the panel to move. - 4
Fasteners
Stainless or aluminum fasteners only, driven snug, never hard enough to dimple soft metal. - 5
Ridge, penetrations and walk-off
Pipe boots and vent flashings get sealed, and installers stay off the flats of finished panels, because aluminum shows footprints.
What to Check on an Aluminum Roofing Quote
Thickness in decimals
Englert gives .023 to .040 inch as the residential range. If a quote names a "gauge" for aluminum, ask for the decimal.Paint system
Aluminum is always prepainted, per JLC. The difference between PVDF (Kynar 500) and SMP finishes is the same as on steel; see standing seam metal roofing.Clips
Floating clips on runs long enough to move.Fasteners
The code accepts stainless steel fasteners on any metal roof. Plain steel screws in aluminum are a corrosion point.Trim and gutters
Aluminum trim and gutters match aluminum panels. Copper anywhere uphill doesn't.Permit
Livonia's permit rules are on our metal roof replacement page.