Metal roofing covers new or replacement panel systems on sloped roofs, plus the retrofit options for an existing metal roof. An aging metal roof with sound panels can often be recovered with a single-ply membrane, sprayed with foam or coated instead of torn off. Replacement makes sense when panels are rusted through or the structure needs repair.
Strong Contractors installs, replaces and restores commercial metal roofing systems, including functional and architectural assemblies. Metal roofing uses interlocking or mechanically seamed panels to create a durable, water-shedding sloped roof system. It is commonly selected for its long service life, resistance to severe weather, low maintenance requirements and architectural appearance.
Common Applications:
Metal roofing must remain securely attached while accommodating thermal movement and directing water through changes in slope and geometry. Strong coordinates the panels, clips, fasteners, underlayment, closures, sealants and flashings as one complete weather-control assembly.
Replace the panels or keep them? Every metal roof project turns on that question, and the steps below cover both paths.
| Spec | Typical Value |
|---|---|
| New panel types | Standing seam (mechanically seamed) and interlocking panels |
| Attachment | Concealed clips with planned fixed points, or through-fastened panels |
| Slope | Sloped, water-shedding roofs; minimum slope set by the panel manufacturer |
| Panel gauge | Typical: 24 or 22 gauge steel, set by design |
| Retrofit: single-ply | Membrane over the existing panels on a leveled substrate |
| Retrofit: spray foam | Foam applied over the panels, then protected with a coating |
| Retrofit: coating | Fluid-applied coating over prepared panels, seams and fasteners |
The biggest cost decision on a metal roof is whether the existing panels stay. After that, these factors drive the number.
Surface rust costs far less to address than perforated panels, which have to be replaced before any retrofit goes on.
New panels, a membrane recover, spray foam and coatings differ widely in material, labor and expected service life.
Adding insulation through spray foam or a recover board raises cost now and can lower energy use over the life of the roof.
Custom flashings at eaves, ridges, valleys, walls and penetrations add shop and field labor, especially on architectural roofs.
Roof height, slope, equipment and work over occupied space affect safety setup, staging and schedule.
| Metal Roofing & Retrofits | Spray Foam (SPF) Roofing | Silicone Roof Coatings | ||
|---|---|---|---|---|
| Existing panels | Removed and replaced | Stay in place | Stay in place | |
| Adds insulation | Only if added under new panels | Yes, the foam insulates | No | |
| Seams and fasteners | New seams and clips | Covered by seamless foam | Sealed, then coated | |
| Panel condition needed | Structure must be sound | Sound panels, rust treated | Sound panels, surface rust only | |
| Disruption | Highest; roof is opened | Low; no tear-off | Lowest | |
| Typical fit | Failed panels or new design | Leaking, uninsulated metal | Aging but sound panels | |
Yes, on panels that are still sound. The coating seals seams and fasteners and covers the surface with a continuous, weather-resistant layer. Preparation decides how long it lasts: rust is removed and treated, loose fasteners are tightened or replaced, and seams are reinforced before the coating goes on.
The manufacturer warranty quoted for your roof is the most reliable guide, because terms are tied to the coating system and the thickness installed. Coating type, applied thickness and panel prep all affect how long it performs. A coated roof can usually be recoated later instead of replaced.
Sealant is a spot treatment that closes a specific seam, joint, fastener or crack. A coating covers the whole roof surface with a continuous membrane. On metal roofs, sealant at seams and fasteners is usually part of the preparation, and the coating then goes over everything.
Yes. A single-ply metal retrofit puts a membrane over the existing panels without a tear-off. The panel ribs are usually filled with insulation or covered with a board to create a flat surface, and the membrane is attached over it. The retrofit can add insulation and cover exposed fasteners with one continuous layer.
Yes. Spray polyurethane foam bonds to prepared metal, fills the panel profile and covers seams and fasteners in one seamless layer that also insulates. A protective coating goes over the foam. Strong is an SPFA Accredited Contractor, and metal is one of the substrates the team sprays.
On through-fastened panels, the rubber washers under each screw age and crack, and daily expansion and contraction can loosen fasteners. Water then follows the screw into the building. Replacing or resealing fasteners fixes isolated leaks; leaks across the whole roof usually mean it is time for a retrofit.
If the panels and supports are sound, a retrofit usually costs less and keeps the building closed to weather during the work. Replacement makes sense when panels are rusted through, the structure needs repair, or the slope or design no longer works. A roof assessment answers the question before either option is priced.
