Yes — in most cases you can install metal roofing over existing asphalt shingles, and it’s a legitimate installation method that saves tear-off labor costs. Arkansas building code generally allows up to two roofing layers. However, overlay has real drawbacks: you can’t inspect the decking, moisture can become trapped between layers, and the added weight may stress older structures. A full tear-off is our standard recommendation.
This is one of the most common questions homeowners ask when exploring metal roofing for their Arkansas homes. The overlay option is attractive because it can reduce installation costs by eliminating tear-off labor and disposal fees — typically $1-$2/sq ft. But the tradeoffs are real and worth understanding before making a decision.
At Lifetime Construction Builders LLC, we’ve been installing and advising on roofing systems across Arkansas since 2009. As a licensed contractor and Atlas Preferred Contractor, here’s our straight-forward guidance on the overlay question.
Code Requirements: What Arkansas Allows
Arkansas follows the International Residential Code (IRC), which permits a maximum of two roofing layers (the original plus one overlay) on residential structures. So if your home currently has one layer of asphalt shingles, adding metal roofing as a second layer is code-compliant in most jurisdictions.
If your home already has two existing roofing layers — which some older homes do — you cannot add a metal overlay. A full tear-off to bare decking is required before any new roofing is installed.
Always verify local ordinances with your local building department, as some municipalities have adopted amendments to the IRC that may be more restrictive than the base code. Our team handles permit research as part of every installation.
Cost Savings from Overlay
The primary appeal of overlaying metal over shingles is cost. Tear-off and disposal of existing shingles typically adds $1-$2 per square foot to an installation — or $1,500-$3,500 on a typical home. For homeowners with tight budgets, this is a meaningful number.
The cost savings are real and not trivial. If budget is the deciding factor and your home has good structural integrity, overlay can be a reasonable choice — as long as you understand the tradeoffs below.
The Case Against Overlay: Why We Recommend Tear-Off
You Can’t Inspect the Decking
The most significant disadvantage of overlay is that the old shingles hide your roof decking. Soft spots, water-damaged plywood, rot, and deteriorated boards are invisible until the shingles are removed. These conditions compromise the structural integrity of your roof deck and, consequently, the holding power of any fasteners or clips attached through it.
We’ve encountered decking in genuinely poor condition on homes where the exterior shingles still looked acceptable. Water infiltration at old flashings, around chimneys, or at valleys can damage sheathing significantly without producing obvious exterior signs. Installing 40-year metal roofing over a compromised deck doesn’t fix the underlying problem — it covers it up.
A professional roof inspection before any installation decision helps identify whether overlay is safe for your specific structure.
Moisture Trapping
Asphalt shingles trap moisture between layers when wet. In hot, humid Arkansas summers — and particularly after rain events — moisture can be trapped between your old shingles and your new metal panels. This trapped moisture needs to escape; if ventilation is inadequate, it can accelerate degradation of both the old shingles and the underside of the metal panels.
This concern is manageable with proper underlayment selection and ventilation design, but it requires attention to details that a basic overlay installation may skip. Not all contractors installing metal overlays address the ventilation implications properly.
Added Weight
Metal roofing is generally lighter than asphalt shingles — standing seam Galvalume weighs 1.0-1.5 lbs/sq ft versus 2.5-4.0 lbs/sq ft for architectural shingles. However, when you’re adding metal on top of existing shingles rather than replacing them, you’re adding weight on top of the existing load.
For most homes with sound framing, this additional weight is within structural tolerances. For older homes with undersized framing, or homes with existing structural concerns, it warrants a structural assessment before proceeding with overlay.
Wavy Appearance
Standing seam metal panels installed over existing shingles will follow the topography of the shingles beneath them. Shingles have thickness variations at overlaps, and those variations can telegraph through the metal panels above, creating a subtle waviness in the finished surface. On a clean decking surface, standing seam panels lie perfectly flat. Over shingles, the surface is inherently less uniform.
This is primarily a cosmetic concern and varies by the specific shingle profile and installation technique. It’s worth discussing with your contractor before committing to overlay.
When Overlay Is Reasonable
Despite these disadvantages, metal-over-shingles overlay is a legitimate installation method when:
- Only one existing shingle layer is present (code compliant)
- A recent inspection confirms decking is in good condition
- The structure has adequate framing for the combined load
- Proper ventilation is maintained or improved
- The appearance of minor waviness is acceptable
- Budget genuinely precludes tear-off
For exposed fastener systems like R-panel, overlay is more straightforward than for standing seam. R-panel’s rib profile bridges over shingle irregularities more effectively than the flat pan areas of standing seam panels.
The Tear-Off Advantage
Our standard recommendation is a full tear-off for several reasons that go beyond code compliance:
- Complete inspection of all decking — no hidden surprises post-installation
- Fresh underlayment on clean decking — optimized for metal compatibility
- Flat, uniform surface for standing seam — no shingle texture telegraphing through
- Elimination of all moisture-trapping old material
- Access to repair any damaged decking before it becomes a problem
- Clean starting point for a 40-70 year metal roof lifespan
If you’ve experienced storm damage that requires significant shingle repair anyway, the incremental cost of full tear-off versus overlay narrows further — and the insurance process may cover tear-off costs.
Getting the Decision Right for Your Home
The overlay question is answered case by case based on your home’s specific conditions. Our team conducts a thorough roof inspection before any installation recommendation — and we’ll give you a straight assessment of whether overlay is appropriate for your structure or whether tear-off is the right call.
See our full discussion of standing seam vs exposed fastener for more context on system selection, and our complete metal roofing guide for an overview of all the considerations involved. For cost planning, see our post on metal roofing cost vs shingles.
Lifetime Construction Builders LLC — BBB A+ accredited, 5.0-star rated, Atlas Preferred Contractor, AR-licensed — is your team for metal roofing decisions in Bryant and across Central Arkansas. Call (501) 307-1440 for a free consultation.