Metal Roof vs Asphalt Shingles: A Decision Table for Upstate Homes

You are replacing a roof in Anderson or nearby, and you have a metal quote and a shingle quote. The temptation is to compare the totals. The better comparison is what each roof does on your house: its slope, its trees, its attic, your HOA and how long you plan to stay.

Anderson Metal Roofing and Shingles installs both residential metal roofs and residential shingle roofs, so this is not a page steering you to one. The site's post on metal roofs vs asphalt shingles covers appearance and cost in general terms. This guide is the decision table: the physical facts, with sources, and the questions each one raises.

Weight first. The Metal Roofing Alliance's FAQ states that metal roofing weighs half as much as asphalt. On an existing house that rarely decides anything by itself, but it matters when a second layer is being considered or when the framing is old or light. Your installer or an engineer can tell you whether weight is a factor.

Slope decides more. The 2021 International Residential Code, in force in South Carolina since January 1, 2023, allows asphalt shingles only on roofs with a slope of two units vertical in 12 horizontal (2:12) or steeper, and from 2:12 up to 4:12 it requires double underlayment (section R905.2.2). For metal panels the minimums depend on the profile (section R905.10.2): lapped panels without lap sealant need 3:12, lapped panels with sealant applied per the manufacturer can go to 1/2:12, and standing seam systems can go to 1/4:12.

So a porch roof, shed dormer or addition with a very shallow pitch is a place where shingles are not permitted and a standing seam or sealed-lap metal panel is. On a typical 6:12 or steeper Upstate roof, both are allowed and slope stops being the deciding factor. Confirm the details with the Anderson County or City of Anderson building department, since local practice and the permit decide.

Both materials are tested, and both can be installed well or badly. The ratings tell you about the product; the installation decides whether the rating means anything on your roof.

• Wind. IBHS, which runs the FORTIFIED program, says roof damage in storms begins when wind gets under the roof edge and pulls the covering away. Just about any roof cover can complete a FORTIFIED roof, with shingles required to meet the highest wind ratings and metal panels tested for site-specific design pressures. Either way the deck nailing, sealed deck and edge details carry the load. The metal roofs in hail, wind and hurricanes guide goes deeper.
• Hail. UL 2218 is the impact test for steep-slope roof coverings. It drops steel balls to mimic hailstone energies and rates products Class 1 through 4. UL itself notes there is no established direct correlation between hailstones and steel balls, and that the test does not evaluate weathering or aging. The Metal Roofing Alliance says most metal roofing earns Class 4, meaning a sample did not crack when hit twice in the same spot by a 2-inch steel ball, and it concedes that all roof types can sustain cosmetic damage in a severe storm. Impact-rated shingles exist too, and IBHS now rates shingles separately for hail performance.
• Fire. ASTM E108 (the same test as UL 790) rates roof coverings in classes, and Class A is the class for severe fire exposure. The Metal Roofing Alliance cites Class A for metal roofs; many shingle assemblies are also Class A. The rating belongs to the whole assembly over your deck, so ask which class your installed roof will carry.

Rain noise is the question everyone asks about metal. The Metal Roofing Alliance's answer is that there is little difference between metal and other materials when it comes to noise from rain or hail. The reason is in the site's commercial page: metal roofs are installed over felt, plywood, synthetic underlayment or an existing roof, and those layers absorb sound. An open-framed barn roof is loud. A house roof over a deck and underlayment is not.

Heat depends on color and finish more than material. The Department of Energy's cool roof guidelines explain that bare metal reflects sunlight well but holds heat because it emits poorly, while painted metal in light or cool-pigment colors rates well on both counts; cool-rated asphalt shingles also exist for steep roofs. Dark conventional shingles run hottest. The what is a cool roof guide covers the ratings and the winter trade-off.

Winter matters less here than in the mountains, but the site's post on shingles vs metal in a colder climate covers snow shedding and snow guards if your roof dumps onto a walkway.

Repairs differ in kind. A shingle roof is repaired shingle by shingle, and the site's shingle page notes most shingles are easy to repair, though the new ones will not match a faded field. A metal panel usually runs from eave to ridge, so damage in one spot can mean replacing a whole panel or living with a touch-up; the site's touch-up paint post explains what touch-up can and cannot do. Shingle-specific failures, such as the blisters described in another post, have no metal equivalent.

Appearance is personal, but the rules are not. Many Anderson-area neighborhoods have HOA covenants on roof color and material. The Metal Roofing Alliance notes that HOA guidelines must be reasonable, consistently enforced and compliant with state and federal law, and that owners can ask for approval or for outdated rules to be revisited. Get the written covenant before you order anything.

On insurance, ask your insurer directly whether an impact-rated or Class A roof changes your premium or deductible, and get the answer in writing. Insurers differ and this guide makes no promise either way. Anderson Metal Roofing and Shingles can inspect and document storm damage with photos and an itemized estimate for your claim; you handle the claim with your insurer.

Metal is the wrong fit when the HOA forbids it, when the budget only reaches shingles and the attic is well vented, or when you are selling soon and the neighborhood is all shingle. Shingles are the wrong fit on a slope under 2:12, on a roof that stays wet and shaded under heavy trees, or when you want the longest service life and a repaintable surface. The metal roof lifespan vs asphalt guide explains what ages each one.

Whichever you lean toward, the contractor matters more than the material. The how to choose a roofing contractor guide covers licence checks, insurance certificates and written warranties.

When you are ready, ask for both quotes from the same company so the measurements, underlayment, flashing and decking allowances match line for line. Anderson Metal Roofing and Shingles gives free quotes and verifies measurements on site; use the quote form.