Metal Roof Retrofit and Restoration in Davenport, IA

The maintenance tech comes down the ladder with a fistful of backed-out screws and a rubber washer that crumbled when he touched it. He has three more leaks on the list for Monday.

That is how most exposed-fastener metal roofs ask for attention. The panels may be fine, but the screws that pin them down have worked loose, and every one is a small hole waiting for a thaw. For a building in Davenport, IA you have two honest paths: restore the roof you have, or put a new metal roof over it. Which one fits depends on what the old roof still has in it.

An exposed-fastener roof is held with screws driven through the face of each panel, sealed by a rubber or neoprene washer under the head. Sun dries those washers out. Heat and cold work the panels back and forth, and the screws loosen in their holes. Over time the holes elongate, the washers crack and water finds the gap.

Panels here work through hot summers and a record low of -29 F, so they travel a long way each year. When the August 10, 2020 derecho blew through, the winds stayed damaging for somewhere between half an hour and an hour over Davenport, Bettendorf and the rest of Scott County, and that is a long time to flex a panel. Rust takes over where the coating has worn through at laps and cut edges. Fixing one screw does not fix a roof full of them.

Restoration works when the panels are sound underneath the wear. The steps run in order:

1. Walk and mark. We find loose, stripped and missing fasteners and bad laps.
2. Re-fasten. Failed screws are replaced with larger-diameter ones and new sealing washers, set into solid purlin.
3. Seal. Tape or sealant goes into lap seams, ridges, end laps and every penetration.
4. Treat the rust. Surface rust is cleaned and primed before anything covers it.
5. Coat. A fluid-applied coating, such as silicone, goes over the whole surface.

The result is one continuous coated surface without a tear-off, and the building keeps working below. The same order holds for coating restoration on any substrate.

Retrofit is the bigger step. A light framing system, usually sub-purlins on spacer clips, is fastened through the old panels to the structure. New standing seam panels then ride on that frame, above the old roof. Because the old roof stays in place, there is no open deck, no tear-off dumpster and little interruption to what happens inside.

The new roof also fixes things the old one could not. The frame leaves a cavity for added insulation, concealed clips let the panels move without opening holes, and the exposed screws are gone entirely. The panels themselves are standing seam panels, so snow guards, trim and clip spacing are handled as they would be on any standing seam roof.

Before a retrofit we check the structure for the added weight and for snow. Snow can lie on these roofs through winter, and the purlins and frame have to carry it.

Four findings usually settle it:

• Panel condition. Surface rust restores. Rust-through at laps and edges argues for a retrofit.
• Fastener holes. If the screw holes in the panels are badly stripped, a bigger screw only buys a season.
• Insulation. Wet or sagging blanket under the panels is easier to correct when there is a new cavity above it.
• How long you plan to hold the building. A long hold supports the larger project. A short hold supports the cheaper one.

We lay both options out on one sheet with the same scope, and we say plainly when a coating would be money thrown at a roof that has run its course.

Exposed-fastener metal is a common roof on light industrial and flex buildings. The Brady Street corridor runs from the downtown riverfront north to I-80, passing retail developments and industrial parks. Eldridge, north of Davenport along U.S. 61, created several industrial parks starting in the late 1960s. A flex industrial roof in a park like those is a candidate for this conversation if it is exposed-fastener metal and the first screws start to back out.

The work happens on a building in use. We agree on lift placement, dock access and the rooftop units that can be shut down for short periods, and we coordinate with tenants through notice letters. Reroofing an occupied building sets the order of work around the production schedule and the dock.

Older metal buildings often carry translucent panels and curb-mounted vents that fail before the steel does. Translucent panels craze in the sun, cloud over and crack at the fasteners. We replace them with the roof, or re-flash the curb. A leaking skylight or penetration can mislead a team into thinking the whole roof is gone.

Inside, the insulation tells the story. Blanket that sags, stains or smells of mildew has been wet, and we flag it in the report with photos so you know how far the damage goes before the first panel is touched.