By The Roofing Brief Team. Last reviewed: October 2026.
The best metal roofing screws for most exposed-fastener panels are ST Fastening’s ZXL WoodBinder #10, a 10-16 Micro-Bit self-drilling screw whose molded ZAMAC zinc-aluminum head carries ST’s lifetime protection against red rust on the head and washer, sold in 1 to 3 inch lengths. US Cargo Control listed the #10 x 1 1/2 inch size at $67.99 per 250 (about $0.27 each) on October 19, 2026. Into steel purlins, step up to a #12-14 self-driller; within 1,500 feet of salt water, use a 304 or 316 stainless screw.
How we picked the best metal roofing screws
This roundup is an editorial ranking built from manufacturer catalogs and spec pages (ST Fastening’s 2020 catalog, SFS and Triangle Fastener product data), installation guides from panel makers Metal Sales and McElroy Metal, the IRC’s fastener rule for metal roofs (R905.10.4), and retail prices checked on October 19, 2026. We did not run hands-on lab or field testing of these fasteners.
The ranking weighs four published criteria: head and washer corrosion protection, drill point matched to the substrate, published pull-out data, and price per screw. Pull-out values in this article are the makers’ own laboratory figures, and ST states its values are ultimate loads that need a safety factor for design, so confirm pricing and any project approvals with the manufacturer before a large order.
Best metal roofing screws at a glance
The table compares the seven picks by size, head and coating, washer, the corrosion claim each maker publishes, and a dated price where one was listed, from $0.13 to $0.33 per screw. Fastener costs move with steel prices, which our metal roofing tariff and import report tracks in detail.
| Screw | Best for | Size / point | Head & coating | Washer | Published corrosion claim | Price checked Oct 19, 2026 |
|---|---|---|---|---|---|---|
| ST Fastening ZXL WoodBinder #10 (Top Pick) | Exposed-fastener panels into wood | 10-16, 1 to 3 in, Micro-Bit self-drill point | 5/16 in cupped hex, molded ZAMAC | EPDM | Lifetime protection against red rust on head and washer (written warranty on request) | $67.99 per 250, #10 x 1 1/2 in (US Cargo Control) |
| ST Fastening Maxx SteelBinder #12 | Metal-to-metal on steel purlins | 12-14, 3/4 to 3 in, drills steel up to 0.210 in | 5/16 in cupped hex; powder coat over zinc and chromate | Encapsulated EPDM | Powder over zinc: over 100 Kesternich cycles for some colors vs 25 to 30 for wet paint (ST catalog) | Distributor quote |
| Triangle Fastener BLAZER stainless cap | Commercial steel framing 0.125 to 0.500 in thick | #12-24, 1 1/4 and 2 in (BLAZER-5) | 304 stainless cap | EPDM | TRI-SEAL coating rated to 1,000 hours salt spray | Distributor quote |
| SFS Bi-Met 300 | Coastal and saltwater zones | #12 bi-metal self-drill (SX14 listing) | 304 or 316 stainless | EPDM options | Stainless head and body for corrosive environments (SFS) | Distributor quote |
| SFS Impax SD3 #12 | Color-matched commercial, light and medium gauge steel | #12 self-drill, HWH | VistaCoat premium coating | With or without bonded seal washer | Coating named; no hour rating found in SFS listings | Distributor quote |
| Teks #9 / Hillman Power Pro #10 | Budget and same-day DIY repairs | #9 x 1 1/2 in; #10 x 1 1/2 in self-drilling | Painted or coated steel | Neoprene (Teks) or steel-backed EPDM (Power Pro) | No lifetime head claim | Power Pro: about $18 to $20 per 98 (Tractor Supply listings) |
| ZXL #12 T-17 WoodBinder | Replacing failed or stripped screws, OSB decks | #12 x 3/4 and 1 1/2 in, Type 17 sharp point | ZAMAC head, Strip-Loc thread | EPDM | No red rust ZAMAC head | $82.95 per 250 for #12 x 1.5 in ZXL dome cap (metalroofingscrews.com) |
Metal roofing screw decision table
Four facts about the roof pick the screw before brand does: the substrate, the panel metal, whether the house is within 1,500 ft of salt water and whether you are re-screwing old holes. Find your row, then check the length rule below the table.
| If you are fastening | Choose | Rule behind it | Source |
|---|---|---|---|
| Steel panels into wood deck or wood purlins | #10-14 or 10-16 woodscrew with EPDM washer | Metal Sales lists #10-14 woodscrews in 1, 1 1/2 and 2 in for PBR panels into wood | Metal Sales PBR guide (4/24) |
| Steel panels into steel purlins, 22 to 12 gauge | #12-14 self-driller | Metal Sales lists #12-14 self-drillers in 1 to 2 in for steel; ST rates its #12 drill point to 0.210 in steel | Metal Sales PBR guide; ST 2020 catalog |
| Bare (unpainted) Galvalume panels | An XL or ZAMAC-head fastener | Metal Sales recommends its XL fasteners for bare Galvalume panels and flashings | Metal Sales PBR guide |
| Copper roof | Copper, brass, bronze, copper alloy or 300-series stainless | Required when the maker gives no other instruction | IRC R905.10.4 |
| Within 1,500 ft of salt water | 304 or 316 stainless (for example SFS Bi-Met 300) | Galvalume panel warranties such as Metal Sales’ AZ55 warranty exclude this zone, so the fastener should outlast a coastal-grade panel | Metal Sales AZ55 warranty |
| Re-screwing stripped holes in OSB or plywood | #12 or #14 Type 17 replacement screw | ST built its #12 T-17 for OSB strip-out and says its #14 Type 17 point cleans the old hole so oversized threads can tap | ST 2020 catalog |
| Sidelaps and trim | 1/4-14 x 7/8 in stitch screw | Metal Sales and McElroy both specify this size for laps and trim | Metal Sales PBR guide; McElroy MM498 |
1. ST Fastening ZXL WoodBinder #10: best overall
The ST Fastening ZXL WoodBinder #10 is our top pick for exposed-fastener metal panels installed over wood purlins or plywood, which covers most agricultural, pole-barn and residential exposed-fastener jobs. ST’s catalog describes a 5/16 inch cupped hex head with a molded ZAMAC zinc-aluminum alloy that provides lifetime protection against red rust on the head and washer, a Micro-Bit point that drills 29 and 26 gauge panels, and threads that go from fine to coarse for grip in wood.
ST’s laboratory pull-out values for the 10-16 screw are 636 lb in 3/4 inch plywood, 441 lb in 5/8 inch plywood, 210 lb in 7/16 inch OSB, and 713 lb at 1 inch versus 1,526 lb at 1 1/2 inches of penetration in 2x yellow pine, all ultimate loads. Best for: Galvalume and other long-life panels where the head should not rust before the panel does.
- Pros: ZAMAC head with ST’s lifetime red-rust protection; EPDM washer; 1 to 3 inch lengths; published pull-out and pull-over tables (927 lb pull-over in 26 gauge Galvalume).
- Cons: $0.27 per screw at the October 2026 US Cargo Control price, about double unbranded zinc #10 screws at $0.13; ST says not to drive its powder-coated or painted screws with impact drivers.
2. ST Fastening Maxx SteelBinder #12: best for steel purlins
The Maxx SteelBinder #12 is the pick when you fasten metal panels directly to steel purlins or tube framing. ST’s catalog says its #12 self-drilling point penetrates steel up to 0.210 inch with no point walking, and its matching 1/4 inch stitch screw fastens sidelaps up to 18 gauge panel thickness. Sizes run from 12-14 x 3/4 inch to 12-14 x 3 inch.
The coating is ST’s powder coat over zinc plating and chromate sealer, which ST’s catalog says withstands over 100 Kesternich chamber cycles in some colors, against 25 to 30 cycles for electroplated zinc and wet paint; one cycle is 8 hours in the chamber and 16 hours outside it. Best for: pre-engineered metal buildings and re-roofs over steel.
- Pros: drills steel to 0.210 inch; cupped head encapsulates the EPDM washer; unpainted versions ship with ST’s DuraSeal Plus coating.
- Cons: the powder-coat head is not the ZAMAC head of the ZXL line; wrong screw for wood substrates.
3. Triangle Fastener BLAZER HWH: best for code-approved commercial
Triangle Fastener Corporation’s BLAZER line is the pick for commercial steel framing where a project specifies a stainless cap. Roofing Contractor’s coverage of Triangle’s BLAZER-5 stainless cap screws lists #12-24 x 1 1/4 and 2 inch sizes rated for attaching steel, aluminum or stainless to steel roughly 0.125 to 0.500 inch thick, with a 304 stainless cap and EPDM washer. Triangle’s TRI-SEAL coating is rated to 1,000 hours of salt spray, which company officials put at more than 20 times the protection of commercial zinc plating, per ACHR News.
Best for: heavy steel framing on commercial roofs where the engineer or insurer asks for fastener documentation. Ask Triangle for the approval listing that applies to your assembly; we found none published for the screw itself, only its 0.125 to 0.500 in drill range.
- Pros: drill capacity to 0.500 inch steel; 304 stainless cap; Triangle vice president Joe Stager’s published tips set a 2,500 rpm maximum and no impact tools.
- Cons: quote-based pricing with no published per-screw figure; usually ordered through Triangle branches.
4. SFS Bi-Met 300: best for coastal and saltwater
Inside a salt-air buffer, the fastener should be stainless. Metal Sales’ 25-year AZ55 Galvalume warranty, for example, does not apply within 1,500 feet of salt water, marine atmospheres or salt spray, so coastal roofs often move to aluminum or coastal-grade panels and need a screw to match. SFS lists its Bi-Met 300 line, including the SX14 #12 self-drilling screw, in 304 or 316 stainless for dissimilar metals, corrosive environments and thick steel.
Best for: beachfront and marine-air roofs, and aluminum panels where a plated steel screw would be the dissimilar metal. The IRC allows stainless fasteners on every type of metal roof under R905.10.4 when the panel maker gives no other instruction.
- Pros: 304 or 316 stainless; bi-metal self-drilling build for steel framing; EPDM washer options.
- Cons: premium, quote-based price; confirm the panel maker’s fastener list for aluminum panels before ordering.
5. SFS Impax SD3 #12: best color-matched long-life commercial
The SFS Impax SD3 #12 is a hex washer head self-drill screw for metal panel to light and medium gauge steel, sold with SFS’s VistaCoat premium coating and with or without a bonded seal washer. SFS’s listing says impact guns and hammer drills are not recommended for installation. We found no salt-spray hour rating for VistaCoat in SFS’s public listings, so ask for the coating data sheet if the spec calls for one.
Best for: visible commercial roofs where head color has to match the panel through the paint warranty.
- Pros: color-matched premium coating; washer optional for metal-to-metal trim; consistent supply through SFS distribution.
- Cons: a coated head is not a molded ZAMAC or stainless head; no published coating hours.
6. Teks #9 or Hillman Power Pro #10: best budget and DIY
For a small repair or a same-day fix, home-center screws such as the Teks #9 x 1 1/2 inch hex washer head metal-to-wood screw or the Hillman Power Pro #10 x 1 1/2 inch self-drilling metal-to-wood screw are stocked at hardware chains. Tractor Supply’s online listings showed Power Pro 98-packs at about $18 to $20 in October 2026, roughly $0.18 to $0.20 per screw, and metalroofingscrews.com listed unbranded #10 zinc metal-to-wood screws with EPDM washers from $32.95 per 250 (about $0.13 each).
Best for: patch repairs, DIY sheds and jobs that need parts today. Ace Hardware’s Power Pro listings describe a steel-backed EPDM washer and a Micro-Bit point.
- Pros: lowest price per screw; available same day; several panel colors.
- Cons: no lifetime head warranty like a ZAMAC or stainless head; 98-count and 100-count packs cost more per screw than 250-count bags.
7. ZXL #12 T-17 WoodBinder: best for replacing failed screws
When you re-screw an aging roof where the original #9 or #10 holes are wallowed out, a larger replacement screw restores the grip. ST’s catalog lists the ZXL #12 T-17 as an OSB and replacement screw with deep threads for soft fibers, a Type 17 sharp point, Strip-Loc thread-to-point design and a ZAMAC head, in #12 x 3/4 and 1 1/2 inch sizes. Its pull-out values in 7/16 inch OSB are 198 lb at 3/4 inch and 212 lb at 1 1/2 inch penetration, and 378 and 739 lb in 2x SPF.
Best for: retrofits, backing-out screw callbacks and OSB decks. For holes too worn for a #12, ST’s #14 Type 17 screw is built so the point cleans the existing hole and the oversized threads tap fresh material.
- Pros: larger diameter re-grips stripped holes; ZAMAC head; built for OSB strip-out.
- Cons: $82.95 per 250 for a #12 x 1.5 inch ZXL dome cap screw at metalroofingscrews.com (about $0.33 each); needed mainly on repair work.
How to choose the right metal roofing screw
Picking a metal roofing screw comes down to four decisions: the substrate (wood or steel), the corrosion zone (inland, or within 1,500 feet of salt water), the head material (ZAMAC, stainless or coated steel), and the length (at least 1/2 inch past the support per Metal Sales, or three full threads past steel per Triangle Fastener). The decision table above maps each one to a screw.
Self-drilling versus self-piercing points
Self-drilling screws have a fluted drill point that bores steel without a pilot hole: ST rates its #12 points to 0.210 inch and Triangle’s BLAZER-5 to 0.500 inch. Self-piercing Type 17 screws have a sharp gimlet point that pierces wood fast, so they suit wood purlins and replacement work, as in ST’s #12 and #14 Type 17 lines. Triangle Fastener’s guidance is to drive drill screws with a 2,500 rpm maximum screwgun and 2,000 rpm or less into steel 1/4 inch or thicker. For a deeper look at one common self-drilling line, see our guide to Teks self-drilling roofing screws.
Head coating: ZAMAC and ZAC versus stainless versus painted zinc
Head material decides how long the fastener looks right and keeps its seal, often for longer than the 15 to 20 year washer. ST’s molded ZAMAC zinc-aluminum head carries lifetime protection against red rust on the head and washer; 304 or 316 stainless suits coastal air; and painted or powder-coated steel over zinc is the budget tier. In ST’s Kesternich chamber figures, electroplated zinc and wet-painted screws last 25 to 30 cycles, while ST’s powder over zinc reaches over 100 cycles in some colors.
The EPDM washer is the waterproofing
The rubber washer, not the threads, keeps water out of the fastener hole; on ST’s #10 heads it sits under a 5/16 in cupped hex. Metal Sales defines correct seating as sealing material slightly visible at the edge of the washer; a deformed washer is too tight and no visible sealant is too loose. ST’s cupped heads encapsulate the EPDM washer, and Triangle recommends a torque-controlled or depth-sensing screwgun to protect it. On fall-protection hardware that also fastens through the roof, our best roof anchor roundup applies the same corrosion-zone logic.
Gauge and length by panel
Most exposed-fastener roofing panels use #10 or #12 screws, with #14 Type 17 screws for oversized replacement holes; Metal Sales’ PBR guide lists #10-14 woodscrews for wood and #12-14 self-drillers for steel. Metal Sales says fasteners should extend 1/2 inch or more past the inside face of the support, and Triangle Fastener’s rule for steel is at least three full threads beyond the substrate. Depth pays: ST’s 10-16 screw pulls out at 713 lb with 1 inch of penetration into 2x yellow pine and 1,526 lb at 1 1/2 inches. See our guides to R-panel roofing and tools for metal roofing for panel-specific specs and the drivers that seat these screws to the right depth.
How many metal roofing screws do you need per square?
Plan for about 80 metal roofing screws per square (100 square feet) on a standard 36 inch exposed-fastener panel with screw lines 24 inches on center, per Western States Metal Roofing. A fast estimate is roof area in square feet times 0.80. Metal Sales gives the same 80 per square for its 3 ft wide Classic Rib panels and 40 per square for 2 ft wide panels, so confirm the layout for your panel before you order.
The table below sets out the common exposed-fastener profiles, the field pattern each uses and the resulting screws per square, from Western States Metal Roofing’s screw guide (March 2020). Our metal roof screw pattern chart shows the row-by-row layout.
| Panel profile | Field fastening pattern | Screws per square (100 sq ft) | Extra lap / trim fasteners |
|---|---|---|---|
| 36″ corrugated (7/8″) | One screw every third corrugation in the high, 4 per screw line, lines 24″ on center | About 80 | Trim: 1 screw per linear foot; no metal-to-metal sidelap screws needed on roofs |
| R-Panel / PBR-Panel | 3 panel screws plus 1 lap screw per interior line, 5 plus 1 at panel ends, in the flat | About 80 | Lap screws 12″ to 18″ on center |
| 7.2 Panel / Western Rib | 5 panel screws in the lows plus 1 lap screw per line | About 80 at 24″ lines | Lap screws 12″ to 18″ on center |
| Any profile, sidelap count | Square footage divided by 3, then by 1.5 | About 22 per square | Western States’ sidelap formula |
Fastener cost per square is Roofing Brief arithmetic: 80 screws times the October 2026 prices above. Unbranded zinc #10 screws at $0.13 come to about $10 per square, ZXL WoodBinder #10 at $0.27 to about $22, and a ZXL #12 dome cap at $0.33 to about $26. Against the $6 to $10 per square foot installed price for exposed-fastener metal in our 2026 cost report, or $600 to $1,000 per square, the screws are about 1 to 4 percent of the job.
Should metal roofing screws go in the flat or the rib?
On R-panel, PBR and 7.2 Western Rib, screws go in the flat beside the rib, per Western States Metal Roofing’s fastener counts. A screw in the flat clamps the panel straight to the deck or purlin and seats the EPDM washer on a flat surface. A screw through the rib crown sits above the drainage plane but spans an unsupported gap above the substrate, which is where panel flex can work the hole.
The common exception is 7/8 inch corrugated roofing, where Western States places the screw in the high of every third corrugation. Whichever position the panel calls for, seating matters as much as position: Metal Sales’ PBR guide warns that overdriven fasteners cause panel distortion. For the full case on each position, see our guide on where to screw metal roofing.
Frequently asked questions
What size screws do I need for metal roofing?
Most exposed-fastener panels use #10 screws into wood and #12-14 self-drillers into steel; Metal Sales lists both in 1, 1 1/2 and 2 inch lengths. Choose a length that extends at least 1/2 inch past the inside face of the support (Metal Sales) or leaves three full threads past steel (Triangle Fastener). Use 1/4-14 x 7/8 inch stitch screws at laps and trim.
Are self-drilling or self-piercing screws better for metal roofing?
It depends on the substrate. Self-drilling screws bore steel without a pilot hole, up to 0.210 inch for ST’s #12 points and 0.500 inch for Triangle’s BLAZER-5, so they suit metal-to-metal work. Self-piercing Type 17 screws pierce wood quickly and are better for wood purlins and for re-seating replacement screws, such as ST’s #12 and #14 Type 17 lines.
What is the best coating for metal roofing screw heads?
A molded ZAMAC zinc-aluminum head, such as ST’s ZXL line with lifetime protection against red rust on the head and washer, is the long-life choice inland. Within 1,500 feet of salt water, 304 or 316 stainless is the better choice. Coated steel heads are the budget tier; ST’s catalog puts electroplated zinc and wet paint at 25 to 30 Kesternich cycles.
Should you use stainless steel screws on a metal roof?
Use stainless near salt water and on copper roofs. IRC R905.10.4 allows stainless fasteners on all metal roofs and requires copper, brass, bronze or 300-series stainless on copper roofs when the maker gives no other instruction. Inland, a ZAMAC-head screw at about $0.27 each costs less than quote-priced stainless.
How long do metal roofing screws last?
The washer usually sets the life, not the screw body. Our 2026 lifespan report puts exposed-fastener gasket life at about 15 to 20 years, while ST’s ZAMAC heads carry lifetime protection against red rust on the head and washer. Budget coated-steel heads have no comparable published warranty.
Can you reuse metal roofing screw holes?
Do not re-drive the same screw into a worn hole. Step up to a larger replacement screw such as ST’s ZXL #12 T-17, built for OSB strip-out, or its #14 Type 17, whose point cleans the old hole so oversized threads can tap fresh material, with a new washer. Retightening a stripped screw does not restore its pull-out value.
How many screws do I need per square of metal roofing?
Plan for about 80 screws per square (100 square feet) on 36 inch panels with lines 24 inches on center, per Western States Metal Roofing, or roof area times 0.80. Add about 22 sidelap screws per square (square footage divided by 3, then by 1.5) and 1 trim screw per linear foot, and confirm against the panel maker’s pattern.
Should metal roofing screws go in the rib or the flat?
On R-panel, PBR and 7.2 Western Rib, screws go in the flat beside the rib, where the screw clamps the panel to the substrate and the washer seats on a flat surface. On 7/8 inch corrugated roofing, Western States places screws in the high of every third corrugation. Follow the panel maker’s pattern and seat the washer until sealant just shows at its edge.