How Much Does an Aluminum Roof Weigh?
Quick answer
An aluminum roof is one of the lightest roofs you can buy — roughly 40 to 50 pounds per roofing square (100 square feet), or about half a pound per square foot. That is a fraction of asphalt (250–400 lbs per square), concrete tile (600–1,100), or slate (800–1,500), which is why aluminum can often be installed over an existing roof.
How much does an aluminum roof weigh?
Aluminum roofing typically weighs about 40 to 50 pounds per roofing "square" — the industry unit for 100 square feet of roof — which works out to roughly half a pound per square foot. To put that in perspective: asphalt shingles run about 250 to 400 pounds per square, wood shakes around 200, concrete tile 600 to 1,100, clay tile 600 to 1,000, and natural slate a crushing 800 to 1,500. Aluminum is, pound for pound of coverage, among the lightest permanent roofing materials made.
Why does roof weight matter?
Weight is dead load your roof structure carries every day for decades. Very heavy materials like slate and concrete tile often require engineered, reinforced framing — and retrofitting them onto a house built for shingles can mean costly structural upgrades. A light aluminum roof does the opposite: it places minimal stress on rafters and trusses, is friendlier in seismic zones, and reduces long-term sag and fatigue on older framing. Less weight overhead is simply easier on the whole building.
Can a lightweight aluminum roof go over my existing roof?
Often, yes — and its low weight is the reason. Because aluminum adds so little load, it can frequently be installed directly over one existing layer of asphalt shingles when local code allows and the deck and ventilation are sound. That avoids the labor, cost, and landfill waste of a full tear-off. Interlock always evaluates the existing deck first; our tear-off-versus-overlay guide explains when going over the old roof is appropriate and when removal is the better call.
Is a lighter roof a weaker roof?
No — this is the key misconception about lightweight metal. A roof's strength comes from the alloy's temper and the panel's engineered profile, not from sheer mass. Interlock's aluminum panels are hardened and deeply formed, and interlock on all four sides, which is why they earn the highest hail-impact rating (UL 2218 Class 4) and stand up to hurricane-force wind while weighing a tenth of what slate does. Light and strong are not opposites in aluminum — they are its signature.
Frequently Asked Questions
How much does an aluminum roof weigh compared to shingles?
Aluminum weighs roughly 40–50 lbs per 100 sq ft, versus about 250–400 lbs for asphalt shingles — aluminum is around one-fifth to one-eighth the weight. That large difference is why aluminum stresses the structure far less and can often be installed over an existing shingle roof.
Does an aluminum roof need extra structural support?
Almost never. Because it is so light, an aluminum roof rarely requires any structural reinforcement — unlike heavy tile or slate, which often do. If anything, replacing a heavy roof with aluminum reduces the load on your framing.
How much does an aluminum roof weigh on a 2,000 sq ft house?
Roof area is larger than floor area, so a 2,000 sq ft home might have roughly 2,200–2,600 sq ft of roof — about 22–26 squares. At ~40–50 lbs per square, that is roughly 900–1,300 lbs of roofing total. The same roof in concrete tile could weigh 13,000–28,000 lbs, which shows why weight drives so many roofing decisions.
Sources
- The Aluminum Association — Weight and density of aluminum building products
- Metal Construction Association — Metal roofing weight and structural load
Explore Interlock Metal Roofing
Last reviewed 2026-07-12 · Reviewed by Scott Plumptree, Director of Marketing