Best suited to
steep-slope commercial, institutional buildings, canopies, and low-slope retrofits over failing systems.
Commercial Metal Roofing, at a glance
Commercial metal roofing covers standing seam panels, metal retrofit over existing roofs, and the metal accents on churches, schools and municipal buildings. It runs long, sheds water fast and lasts decades when the fasteners and seams are specified right. John Beal Roofing installs and repairs commercial metal across St. Louis. Call (314) 429-6000.
The Short Version
Whether This System Fits Your Building
Service life
30 to 50 years for the panel, with coatings and fasteners as the shorter-lived parts.
What to watch
Fastener backout and oil-canning at the panel ends, plus every penetration cut after the original install.
Commercial metal: new systems and retrofits over existing panel
Metal covers a great deal of warehouse, industrial and agricultural square footage in this region, and most of the work is not new construction.
Standing seam is the system for anything being built new or fully replaced. Concealed clips let long panel runs expand and contract with temperature, which on a warehouse-scale roof is significant movement across a season, and nothing holding the roof down sits exposed to weather.
Exposed-fastener panel covers enormous acreage on older commercial and agricultural buildings, and it fails predictably. The neoprene washers under thousands of screw heads dry out, compress and back out over fifteen to twenty years, and the roof develops widespread minor leaks rather than one locatable failure. Re-screwing with oversized fasteners buys real time for far less than replacement.
Retrofit framing is the option most owners do not know exists. A sub-purlin system installs over the existing metal roof, insulation is added in the cavity, and a new standing seam roof goes on above it, without tearing off the old roof, without disposal, and frequently without interrupting operations below. At warehouse scale that economics is difficult to beat.
Condensation is the metal-specific problem here. A panel over an unconditioned or poorly insulated space reaches dew point readily, and the resulting drip gets reported as a leak that no amount of roof work will resolve. Diagnosing it correctly means examining insulation and vapor control rather than chasing fasteners across the roof.
Oil canning, the visible waviness in flat panel areas, is an aesthetic characteristic of light-gauge metal rather than a defect, and it is influenced by substrate flatness and panel handling. Heavier gauge and striated or ribbed profiles reduce it noticeably.
Coating an existing metal roof is a legitimate restoration path where the panels are sound and the fasteners have been addressed, sealing seams and laps while adding a reflective surface to a building that is expensive to cool.
Installation
Where These Roofs Actually Fail
Membrane failures are almost never in the middle of the sheet. It starts at the curb flashing, the pipe boot, the wall termination and the drain.
That is where our crews spend their time, on the parts nobody takes pictures of. Seams go fast. Curbs, rebuilt properly, take an afternoon, and they are what gets a roof to year twenty.
Registration of the manufacturer warranty is part of the job, putting coverage on record under your address instead of in a drawer.
Related: Self-storage facility roofing
Common Questions
How long will this roof last in St. Louis?
Forty years and beyond for standing seam with a quality finish. Exposed-fastener panel is the shorter-lived version, because the washers under the screws — not the steel — are what age out.
Can we recover over the existing roof instead of tearing off?
This is where metal is strongest. A retrofit sub-purlin framing system installs over the existing metal roof, adds insulation in the cavity, and carries a new standing seam roof above — no tear-off, no disposal, minimal interruption below.
Do you install this system yourselves?
Yes. Metal work requires panel handling, flashing fabrication and correct clip layout, and we run our own crews on it rather than brokering it to a panel installer we have not worked with.
What does a repair on this system cost versus replacement?
Re-screwing an exposed-fastener roof with oversized fasteners is inexpensive and buys real years. Replacement or retrofit becomes the answer once the panels themselves have corroded at the laps.
How disruptive is the installation?
Retrofit framing over an existing roof is remarkably undisruptive because the old roof stays in place as the weather barrier while the new one goes up above it. Full tear-off on a metal building is a different matter.
Free Roof Evaluation
Tell us about the building and a dispatcher will call to schedule.