Westlake homes are built to a higher spec than most, and more of them are getting standing seam metal: full roofs on modern farmhouses, accent roofs over porches and bays on stone estates, and low-slope patio roofs out back. When the plans come from an architect, the metal is usually named: PAC-CLAD, Englert, Drexel Metals or McElroy Metal.
I’m Blake Snow, and I’ve been roofing for 30 years. We run our own roll formers, and we also install named manufacturer systems when the job calls for them. Here’s how these four compare, using each maker’s own published data.
The four makers in one paragraph each
- PAC-CLAD (Petersen). Petersen started in Chicago in 1965 and is now based in Elk Grove Village, Illinois. Carlisle Companies bought it in 2019. Since 2024 it’s part of Carlisle Architectural Metals, alongside Drexel Metals. Source: Petersen About page.
- Englert. Englert makes standing seam panels and roll-forming machines and runs an in-house paint line. Source: Englert A1300 page.
- Drexel Metals. Founded in 1985. The current company was formed in 2009 and is now part of Carlisle Architectural Metals. Sources: Drexel About and Petersen’s About page.
- McElroy Metal. Based in Bossier City, Louisiana. Its Maxima family is one of the broadest mechanically seamed lines. Source: McElroy Maxima page.
Snap-lock panels (steeper roofs)
Snap-lock panels click together over hidden clips. No seaming tool needed. They’re the usual pick for main roofs on houses.
| Panel | Seam height | Minimum slope | Widths | Material | Ratings noted by maker |
|---|---|---|---|---|---|
| PAC-CLAD Snap-Clad | 1¾” | 2:12 recommended in most applications | 10”-18” (ICC-ES ESR-4173) | 24 or 22 ga steel; aluminum | Class A (ESR-4173); high-performance clip for UL 90 assemblies; 35-yr non-prorated finish warranty available |
| Englert Series 2000 | 1¾” | 3:12 | 12”-18” | 26, 24, 22 ga steel; .032/.040 aluminum | UL 90 (specific assemblies). Englert calls it its most popular system |
| Englert Series 1500 | 1½” | 3:12 | 12”-20” | 26, 24, 22 ga steel; .032/.040 aluminum | UL 90 (specific assembly) |
| Drexel DMC 175S | 1¾” | 2:12 | 12”, 14”, 16”, 18” | 22/24 ga painted Galvalume; .032/.040 aluminum | UL 2218 Class 4, UL 580 Class 90, UL 790 Class A, Texas Department of Insurance approval |
| McElroy Medallion-Lok | 1¾” | 3:12 | 12”, 16”, 18” | 24 ga Galvalume std; 22 ga or .032 aluminum on request | UL 2218 Class 4, UL 580 Class 90, Class A, TDI |
Sources: PAC-CLAD Snap-Clad, ICC-ES ESR-4173, Englert Series 2000 and Series 1500 profile sheets, Drexel DMC 175S, McElroy Medallion-Lok.
Mechanically seamed panels (low slopes and long runs)
Mechanically seamed panels are folded shut with a seaming tool, at 90 degrees (single lock) or 180 degrees (double lock). They’re rated for much lower slopes, which makes them the answer for porch roofs, patio covers and modern low-pitch designs.
| Panel | Seam height | Minimum slope | Widths | Material |
|---|---|---|---|---|
| PAC-CLAD Tite-Loc / Tite-Loc Plus | 2” (90° / 180° lock) | As low as ½:12 | 12”, 16”, 18” | 22/24 ga steel; .032/.040 aluminum |
| Englert Series 1300 / A1300 | 1½” | ½:12, solid deck required | 12”-20” | 26/24 ga steel, .032 aluminum, 16 oz copper, RHEINZINK zinc |
| Drexel DMC 150SS | 1½” (single or double lock) | 1:12 | 12”, 16”, 20” | 24 ga Galvalume, .032 aluminum, 16/20 oz copper, zinc |
| Drexel DMC 200S | 2” | ½:12 | 12”, 14”, 16”, 18” | Steel, aluminum, copper, zinc |
| McElroy Maxima 1.5 / 2” / 3” | 1½” / 2” / 3” | 1:12 / ½:12 / ¼:12 | 12”-18”; 18” and 24” for 3” | 24 ga Galvalume std; 22 ga and aluminum on request |
Sources: PAC-CLAD Tite-Loc Plus, Englert Series 1300 profile sheet, Drexel DMC 150SS and DMC 200S, McElroy Maxima flyer.
A few details from those documents that matter on a big Westlake roof:
- McElroy Maxima can be jobsite-formed with panel lengths up to 250 feet, which avoids end laps. Its floating clips allow 3⅛” of thermal movement.
- Drexel DMC 150SS can be curved for barrel roofs and cones. McElroy says only Maxima 1.5 and Maxima ADV can be curved.
- Englert’s A1300 is the panel Englert requires for slopes under 3:12.
- Copper and zinc are available in some mechanically seamed lines (Englert 1300, Drexel 150SS and 200S). That’s handy when a bay roof needs to match copper gutters. See our Revere copper post and zinc post.
For more on the seam types themselves, see snap-lock vs. mechanically seamed standing seam.
Hail ratings: what they mean
Several of these panels list UL 2218 Class 4 impact ratings, including Drexel DMC 175S and DMC 200S and McElroy Medallion-Lok. Two things to know:
- Ratings belong to a tested assembly: the panel, gauge, clip and substrate. Change one and the rating may not carry over.
- Class 4 means the panel didn’t crack or leak in the test. It doesn’t mean metal can’t dent. Read the cosmetic-damage language in your insurance policy.
Some Texas insurers offer discounts for impact-rated roofs. See our guide to the Texas impact-resistant roof discount and metal vs. Class 4 shingles.
Oil canning: the honest answer
PAC-CLAD and McElroy both say it plainly in their product documents: oil canning, the slight waviness you can see in flat metal pans, is not a cause for rejection. It’s a natural trait of flat metal, whoever makes it. McElroy recommends striated panels to reduce it. On a Westlake home where the roof is seen from a long driveway, we talk about striations, pencil ribs and panel width before anything is ordered.
Named system or our own panels?
We run our own roll formers for standing seam and R-panel, in 24 or 26 gauge, and lead time is typically 1 to 2 weeks. For most homes, that’s the fastest way to a clean, tight standing seam roof. A named manufacturer system makes sense when:
- An architect, builder or HOA specifies one by name
- You want a manufacturer weathertightness warranty on a qualifying system
- The roof needs copper or zinc, a curved panel or a very low slope
- A finish needs to match an existing building
Either way, the panels are installed to the manufacturer’s specs by certified installers, and our workmanship warranty runs from 10 years up to lifetime, depending on the job.
What we check on every Westlake metal roof
- Roof slope at every plane, including porches and back patios
- Panel type, seam height, gauge and width against the slope and the look you want
- Underlayment and deck, including high-temp underlayment where the maker calls for it
- Clip spacing and fixed vs. floating clips for Texas heat
- Trim, ridge, valley and wall details, plus how gutters tie in
- A free digital photo report
After a storm
Get your metal roof inspected and photographed before anyone repairs it. In Texas you generally have 1 year from the date of loss to file a claim, but check your policy. See our storm damage page.
Talk to us about standing seam in Westlake
We work in Westlake, Southlake, Trophy Club, Keller and Colleyville. See our Westlake standing seam page. We’re certified with GAF, CertainTeed, Owens Corning, Atlas, Johns Manville, Carlisle, Tropical Roofing Products, Mule-Hide and Enviroshake, and many other roof manufacturers. We’re BBB A+ rated, with 5.0 stars on Google at all three offices: Bridgeport, Decatur and Rhome. Request a free inspection or call (817) 733-9228.
