R-Panel and Other Screw-Down Profiles
All of these panels are exposed-fastener roofs. Each sheet is held by screws with rubber washers driven through the face, which is what makes them quick to put up and cheaper than standing seam. They differ in rib shape, sheet width and how the side laps meet.
R-Panel
R-panel is the trade's generic name for a sheet with tall trapezoid ribs on a 12-inch spacing, and suppliers use it for both the plain profile and PBR. You'll see it on Midland shops, barns and a good number of ranch houses. A 36-inch sheet covers a roof quickly, and the tall ribs are why makers rate it for far lower slopes than 5V crimp.
- Coverage: 36 in per sheet
- Rib: 1-1/4 in tall, 12 in on center
- Lengths: 5 to 50 ft on one maker's sheet, cut to the run
PBR Panel
PBR is R-panel with a purlin-bearing leg on the side lap. The overlapping sheet rests fully on the one beneath it, so the lap sits flat on the purlin and closes up tight. One supplier only sells PBR for that reason and says it's the one to use on a roof.
- Gauge: 26 standard, 24 and 22 optional on one maker's sheet
- Lowest slope on maker sheets: 1/2:12 on one, 1/12 on another
- Lap: a bead of mastic on each roofing overlap
5V Crimp
5V crimp has small V-shaped ribs only half an inch tall instead of tall trapezoids, so the sheet looks flatter from the ground. The trade-off is slope: one maker rates its 5V for 3:12, where its PBR goes down to 1/2:12.
- Coverage: 24 in per sheet
- Rib: 1/2 in tall, 12 in on center
- Lowest slope on one maker's sheet: 3:12
- Gauge: 29 standard, 26 optional
26 vs 29 Gauge Exposed-Fastener Panels
A lower gauge number means thicker steel. Materials alone run $1 to $3 per sq ft for 29 gauge and $1.50 to $5 for 26 in HomeGuide's table. That gap is small next to the labor, and 29 gauge is the light sheet sold for sheds. The full gauge table, and how gauge relates to hail, are on the Class 4 metal roof page.
Why Midland homeowners call Midland Metal Roofing
- Free quotes, no obligation to hire
- Panel, gauge and price in writing before any work
- Your request goes to one Midland roofer, not a call list
- Homeowners never pay us for the referral
R-Panel Over a House Deck vs Open Purlins
R-panel and PBR can go over open purlins, as on a barn or shop, or over a solid deck with underlayment, as on a house. The panel is the same either way. What changes is what goes under it.
On a house
panels go over decking and underlayment. If the old shingles stay, the metal roof over shingles rules apply.On a shop or barn
panels span purlins. Ask how condensation on the underside will be handled; one maker sells a Drip Stop option for exactly that. A shop or barn re-sheet is covered on the metal building roof page, and living space under panels on barndominium metal roofs.Slope
the 2018 IRC lets lapped panels go to 3:12 without sealant and 1/2:12 with it. The slope rules for every panel type sit on the standing seam page.
The screws are the weak point on any exposed-fastener roof. Heat cycles work them loose over the years, and the washers age. When they start to leak, see metal roof screw replacement. When you're getting quotes, ask what screw and washer the roofer uses, how many per sheet, and whether the price includes sealant in every lap and closures at the ridge and eave.