Roof edge metal, coping, and fascia: the wind design that keeps them on

Roof edge metal, and why the edge fails first

Roof edge metal is the formed sheet metal that caps the perimeter of a low-slope roof: the fascia and drip edge along an open eave, the coping over a parapet wall, and the gravel stop that holds back ballast or aggregate. It is the line where the flat field of the roof ends and the building turns down to the wall. It is also the single most important wind detail on the whole roof, and the one most often built like an afterthought.

Here is why it matters more than the field. Wind does not push a roof down. It pulls it up. The fastest air and the highest suction live right at the edge and the corner, and the edge metal is the first thing that suction reaches. When the metal lifts, it stops being a cap and becomes a scoop. Now the wind has a way in under the membrane, and from there it works across the field.

So the edge is the failure that takes the roof. A membrane field can be welded perfectly and probe tight everywhere, and the roof still ends up in the parking lot because nobody rated the fascia for the design wind or pulled the cleat tight. The trade has known this for decades, which is why there is a national standard written for nothing but the edge. The field of the roof has its own QA, covered in the companion guide on single-ply seams. This guide is about the perimeter, and the perimeter is where the wind gets its grip.

How a wind event peels a roof from the edge

Watch the post-storm photos and the pattern repeats. The roof did not fail in the middle. It unzipped from a corner or an edge inward, and the first thing gone is almost always the metal.

The sequence is mechanical and it is fast. Suction at the perimeter lifts the leading edge of the fascia or coping. If the metal is only face-fastened with screws through the front, those screws are loaded in withdrawal, the weakest way to load a fastener, and they back out or tear through. Once the front edge of the metal flaps up, the airstream catches the underside and the prying force multiplies. The metal peels back like a sardine lid, and it takes the membrane termination with it, because the membrane was clamped or welded to that metal.

Now the membrane edge is open. Wind drives in under the sheet, pressurizes the space between membrane and insulation, and that internal pressure adds to the external suction. The two work together to billow the membrane, pop the field fasteners or break the adhesive, and roll the roof up from the edge toward the center. The field never had a chance. It failed because the edge let go first. That is the whole argument for treating edge metal as a structural element and not as trim, and it is why the design wind for the edge is figured at the corner, where the suction is worst.

What is ANSI/SPRI ES-1?

ANSI/SPRI/FM 4435/ES-1 is the national standard that sets how roof perimeter edge metal is designed and tested for wind, and it is the document the building code points to for low-slope edges. It is published jointly under ANSI, SPRI (the single-ply roofing trade group), and FM, and it covers fascia, gravel stops, and coping used with built-up, modified-bitumen, and single-ply roof systems. It does not cover external gutters, which have their own standard.

The code makes it mandatory, not optional. The International Building Code requires metal edge systems on low-slope roofs to be designed for the wind loads of its structural chapter and tested for resistance to those loads using the ES-1 test methods. The provision lives in the IBC roof-assembly chapter, commonly cited around Section 1504.5, though the exact number shifts between code cycles, so confirm it against the adopted edition and any local amendments. ES-1 defines low slope as 2:12 or flatter, which is where this whole conversation applies.

What this means on the job is concrete. The edge metal you install has to have an ES-1 rating, and that rating, expressed as a tested pressure or load, has to meet or beat the design wind pressure calculated for that building and that zone. A shop-fabricated edge with no test behind it does not satisfy the code, even if it looks identical to a rated one. The rating is the proof, and the submittal is where you show it. Treat ES-1 the way you treat a fire rating: it is a tested number, not a claim.

Fascia, coping, and gravel stop: the edge types

Three edge conditions cover almost everything on a low-slope roof, and each one caps a different geometry. Knowing which one you are on tells you which ES-1 test applies and which way the loads run.

The fascia, or drip edge, is the metal along an open roof edge with no wall above it. The membrane runs up and over a raised cant or wood blocking, and the fascia laps down over the face of the building, with a hemmed drip at the bottom that throws water clear of the wall. The gravel stop is a fascia variant that also forms a raised lip to hold aggregate or ballast on the roof side. Both are primarily loaded by horizontal, outward suction on their vertical face, the load the RE-2 test measures.

The coping is the cap over a parapet wall, the short wall that runs up past the roof level around the perimeter. The coping covers the top of the wall and laps down both faces, the roof side and the street side, and it has to shed water, hold against uplift, and look straight from the ground. Because a parapet sticks up into the airstream, the coping sees both upward and outward load, which is why it gets the more demanding RE-3 test. The mistake is treating coping as just a wide fascia. It is not. It anchors on two faces and it lives higher in the wind, so it earns its own detail and its own rating.

What is a continuous cleat?

A continuous cleat is a strip of metal fastened along the building edge or wall whose top is bent into a hook, and the edge metal's bottom is hemmed into a matching hook that locks over it. It is the detail that turns a piece of trim into a wind-resistant edge, and it is the difference between a fascia that holds and one that peels.

The mechanic is the point. When the bottom hem of the fascia or coping hooks over the cleat, an uplift force on the metal pulls the hem against the cleat in shear and tension along its whole length, not on a row of screws. The cleat itself is face-fastened to solid blocking on a tight pattern, so the load travels metal-to-metal into the cleat and then into the structure. A continuous cleat engages every inch of the edge. A handful of face screws engages only where the screws are.

This is why a face-fastened edge with no cleat blows off. Run screws through the front of the fascia and you are loading them in withdrawal, straight pull-out, which is the weakest direction for any fastener and the one wind exploits first. The screw heads also telegraph oil-canning and they leak as the holes work open. The continuous cleat hides the fastening, locks the edge along its full length, and gives the wind nothing to grab. On any edge that has to carry real design pressure, the hemmed drip locked onto a continuous cleat is the detail, and an exposed face fastener as the only attachment is the failure waiting for a storm. Confirm the cleat gauge, the hem dimension, and the cleat fastening against the ES-1 rated assembly, because the rating is for the cleat and the metal together, not the cover alone.

Why is the corner the worst place on the roof?

The corner is the worst place because wind suction is highest there, often two to three times the uplift in the middle of the roof, so the edge metal in a corner has to be rated for far more pressure than the same metal in the field. Wind loads are figured under ASCE 7, and the standard divides a low-slope roof into zones by how hard the air pulls.

The zones run from the edge in. The field, the broad center, sees the lowest uplift. The perimeter, a band along every edge, sees more. The corner, where two perimeter bands cross, sees the most. The edge band commonly extends in from the perimeter a distance set by the building size and height, often the lesser of 10 percent of the least plan dimension or 40 percent of the mean roof height, with the corner formed where two of those bands overlap. That width is the older ASCE 7-10 zone method; ASCE 7-16 reworked the roof zones into a height-based geometry, so let the engineer's current ASCE 7 calculation set the actual zone widths and pressures. Air separating over a sharp building corner spins up vortices that concentrate suction right at the metal, which is exactly where your edge detail sits.

Two things drive the number besides location: building height and exposure. A taller building in open exposure sees higher pressure than a low building shielded by surroundings. The design wind speed for the site feeds the calculation. The result is a design pressure, in pounds per square foot or pounds per linear foot, for each zone, and the edge metal in the corner has to carry the corner number. The error that kills roofs is rating the whole perimeter for the field pressure and forgetting that the corner is a different, harsher world. Size the edge to the corner zone where it sits in the corner, and let the engineer's ASCE 7 calculation, run against the adopted code and any FM requirement, set the actual pressures.

ES-1 testing: RE-1, RE-2, and RE-3

ES-1 proves an edge with three pull tests, and each one loads a different edge type the way the wind would. The rated result is a pressure or load the assembly survived, and the design job is to confirm that number meets the calculated design pressure for the zone. The tests are run on the complete assembly, the metal, the cleat, and the fastening together, not on a sample of sheet.

RE-1 tests the edge metal's ability to restrain an unadhered membrane at the perimeter, the case on a ballasted or mechanically attached roof where the membrane is not glued down near the edge. It pulls the membrane against the metal and measures the restraint in pounds per linear foot. It is the least common of the three because it only applies when the membrane is loose at the edge. RE-2 tests a fascia or gravel stop under outward, horizontal load on its vertical face, reported as a pressure the face resisted. That is the dominant failure mode for an open edge, the face peeling outward, so RE-2 is the workhorse test for fascia.

RE-3 tests coping, and it loads the cap both ways, upward and outward, because a parapet cap sees both. It is the most demanding of the three and it is the one a coping submittal lives or dies on. Read an ES-1 report and you are looking for the test method that matches your edge, the rated pressure, and the assembly description, including the gauge, the cleat, and the fastener spacing the rating was earned with. Change the gauge or open up the fastener spacing in the field and you have walked away from the tested assembly and the rating no longer applies.

Coping: the parapet cap and its slope

Coping is the metal cap that finishes the top of a parapet wall, and it does three jobs at once: it keeps water out of the wall, it holds against wind on a part of the building that sticks up into the airstream, and it is the most visible sheet metal on the project from the ground. Get any of the three wrong and someone notices.

Slope it to the roof, not the street. A coping should pitch its drainage to the roof side so water that runs off the cap lands back on the membrane and goes to the drains, not down the face of the building where it streaks the wall, freezes in the joints, and finds its way behind the cladding. A back-pitched coping that drains to the street is one of the most common detailing mistakes, and it shows up as staining on the facade within a year and as wall saturation behind it over time. The pitch is built into the wall framing or the coping itself, commonly a small cross-slope, with the high side at the street edge.

Anchor it on both faces. A coping laps down the roof side and the street side, and both legs need a continuous cleat or an equivalent anchor, because uplift tries to lift the whole cap and outward load works each face. Anchoring only the roof side and face-fastening the street side, or trusting the cap to sit on the wall under its own weight, is how copings end up peeled back over the parapet after a blow. The cap also has to span the wall true and flat, so the wood blocking on top of the wall has to be level and continuous, since a coping telegraphs every dip in the substrate under it.

Coping joints and the splice plate

Coping comes in lengths, commonly 8 to 12 ft, so the cap is a run of sections with a joint between each one, and the joint is where coping leaks and where it has to move. The detail that handles both is the splice plate, sometimes called a backer or cover plate.

A concealed splice plate is a short piece of matching metal, often around 6 to 8 in wide, that sits under the joint and bridges the two coping sections. The coping ends butt over it with a small gap, and the plate carries sealant strips so it seals the joint while letting the two sections slide independently as they expand and contract. Done right, the plate acts like a little internal gutter under the joint, catching any water that gets past and draining it back to the roof side. The coping sections are not fastened tight to each other. They float over the plate, which is the whole point.

The other good joint is a standing-seam or covered joint, where the two sections are turned up and capped, the same idea as a panel seam, which sheds water well but generally wants shorter sections. Whichever you use, the rule is the same: the joint stays watertight and it stays free to move. The failure is a coping lapped and screwed tight section to section with a bead of caulk over the butt joint. That joint is rigid, so the thermal movement has nowhere to go, and it is sealed only by surface caulk, so it leaks the day the caulk lets go. Caulk over a butt joint is not a coping joint. The concealed splice plate with sealant strips is, and it is what the better manufactured coping systems are built around.

Thermal movement and joint spacing

Metal expands when it heats and contracts when it cools, and on a long edge run that movement is real, not theoretical. A 20 ft run of aluminum coping can move on the order of a quarter inch between a hot afternoon and a cold night, and aluminum moves about twice as much as steel for the same temperature swing. If the run cannot move, something has to give, and what gives is the sealant, the fasteners, or the metal itself.

So you build in joints that float. The splice-plate joints between coping sections are the movement joints on a coping run, and the run length between true expansion joints is set so the accumulated movement stays within what the joint can absorb. Common practice places expansion joints roughly every 20 to 30 ft for aluminum and every 40 to 50 ft for steel, with the exact spacing tied to the metal, the color, and the local temperature range, since a dark cap in a hot climate moves more. Confirm the spacing against the manufacturer's system, because the rated joint detail assumes a maximum run.

Skip the movement detail and the failure is predictable. A long rigidly-lapped run buckles, oil-cans, and lifts in the heat, then in the cold it pulls the joints open and splits the sealant. You see it as waves in the coping that were not there at install, as popped fasteners, and as joints that gap in winter and leak. The fix after the fact is cutting the run and adding joints, which means pulling metal. Build the joints in at the right spacing the first time and the run lives with the weather instead of fighting it.

Fastening into the nailer: the load path

Edge metal is only as strong as what it is fastened to, and what it is fastened to is the wood nailer, the continuous wood blocking around the perimeter that the cleat and the metal screw into. The nailer is part of the load path, not a convenience. The uplift on the metal travels into the cleat, the cleat into the nailer, and the nailer into the structure, so a weak nailer is a weak edge no matter how good the metal is.

Size and place the blocking to do the work. The nailer has to be wide enough to catch the horizontal leg of the edge metal, so a 2x6 is usually the right call since it extends past the typical 4 in flange, and it has to sit flush with the insulation so the metal lies flat. It runs continuous around the perimeter, lapped and fastened at the joints, with its height matched to the membrane and insulation thickness. NRCA now recommends untreated wood for roof blocking rather than pressure-treated, because the preservatives in modern treated lumber are corrosive to the fasteners and the metal sitting on them. If treated wood is required, isolate the metal from it.

The nailer anchorage is the part that gets shorted, and it is the designer's call to make, not the field's to guess. The fastener type, size, and spacing that hold the nailer to the structure have to resist the same wind forces as the edge metal above it, and that schedule belongs on the drawings. A nailer toe-nailed or shot down on a loose pattern pulls off the deck as a unit, taking the cleat, the metal, and the membrane with it, and the photos look like the metal failed when the real failure was underneath it. Confirm the nailer attachment and the cleat fastener spacing against the engineered uplift, the ES-1 rated assembly, and on an insured roof the applicable FM requirement, because the pattern is calculated, not chosen on the roof.

The membrane termination at the edge

The edge is also where the membrane ends, and how it ties off there decides whether the perimeter is watertight as well as wind-tight. The metal and the membrane are one detail at the edge, not two trades passing in the night.

On a fascia or gravel stop, the membrane commonly runs up and over the raised blocking or cant and is fastened along the top, then the metal laps down over it and the membrane's outer edge is sealed or clamped under the metal flange. The membrane has to be mechanically secured at the edge, not just adhered, because the adhesive alone will not hold the perimeter against uplift. On a coping, the membrane turns up the inside face of the parapet and terminates near the top, usually under a termination bar, a continuous metal bar screwed through the membrane into the wall blocking with a bead of sealant along its top edge, and the coping caps over all of it. The termination bar is doing structural work, holding the top of the base flashing against the wall, and the sealant caps the exposed edge so water cannot run behind it.

Where this ties into the field is the part crews rush. The membrane termination at the edge has to be continuous with the field membrane and welded or spliced to the same standard, because a perfect field seam that ends in a sloppy edge termination still leaks at the edge. The same seam QA that governs the field, covered in the companion single-ply seam guide, governs the membrane right up to where the metal takes over. Confirm the termination detail against the membrane manufacturer's published edge detail, since the warranty covers the edge tie-in and the rep will check it.

Gauge, finish, and dissimilar metals

The metal itself has to be heavy enough for the span and the wind, finished to last, and compatible with everything it touches. Get the gauge or the metal wrong and the edge either flexes and oil-cans or it corrodes at the fasteners and the laps.

Gauge is set by the wind and the span, and it is part of the ES-1 rating, so it is not a place to value-engineer quietly. A heavier gauge resists the outward and uplift loads with less deflection and holds a straighter line over a long run. Common edge metal runs in the range of 24 to 22 gauge steel or comparable aluminum thicknesses, going heavier where the design pressure is high or the face is tall, but the controlling number is the gauge the ES-1 assembly was tested with. Drop below it and the rating does not apply, and a thin fascia on a tall face waves in the wind and pumps the fasteners loose over time.

Finish and metal compatibility are the longevity questions. A factory PVDF finish, commonly known by the Kynar 500 trade name, holds color and resists chalking and fade far longer than a standard polyester, which matters on coping that everyone sees from the street. The trap is dissimilar metals. Put copper, aluminum, steel, and stainless in wet contact and the more active metal corrodes, fastest where a small area of one metal contacts a large area of another. Copper draining onto aluminum or galvanized steel eats it. Bare steel fasteners in aluminum coping rust and stain. Match the fasteners to the metal, use stainless or coated fasteners rated for the assembly, and isolate unavoidable dissimilar contacts with a gasket or a barrier coating. The edge lives outdoors getting wet for thirty years, so the galvanic pairing is not a detail to leave to whatever is in the bin.

Gutters and scuppers at the edge

Where the edge also drains the roof, the gutter and the scupper join the detail, and they carry their own wind and water requirements. An external gutter hung off the fascia is sheet metal in the wind just like the edge, and it has a separate standard: ANSI/SPRI GT-1, the test standard for external gutter systems, because ES-1 specifically does not cover gutters. On a building with hung gutters, confirm the GT-1 rating the same way you confirm the ES-1 rating on the fascia.

Scuppers are openings through the parapet that let water out at the edge, used as primary drainage on some roofs and as overflow on many. The scupper is a sheet metal sleeve through the wall, soldered or welded watertight and flanged onto the membrane on the roof side, and it has to be flashed into the coping or the wall above it so water cannot run behind the cap. The detail gets busy where a scupper passes under a coping, and that intersection is a common leak point, so it deserves a real section drawing, not a field decision.

The water side ties straight to drainage design. Overflow scuppers are a code requirement on roofs that can pond if the primary drains clog, and their size and inlet height are set by code and by the structural water-depth limit, the same logic covered in the companion guide on roof crickets and tapered insulation. The edge is where that overflow leaves the roof, so the scupper at the edge and the slope feeding it are one problem. A scupper with a flat dead run in front of it ponds at the very spot it is meant to drain. Slope the roof to the scupper, flash it into the edge metal, and confirm the overflow sizing against the adopted plumbing and building code.

The shop drawing and the ES-1 submittal

The submittal is where the edge gets proven on paper before it gets built, and on a wind-rated edge it is not a formality. The shop drawing and the ES-1 documentation together are what the reviewer, the inspector, and the warranty rep read to confirm the edge meets the design wind, and they are what you QA the installed work against.

A complete edge submittal carries a few things. The ES-1 test report for the system, showing the test method that matches the edge type, the rated pressure or load, and the tested assembly: gauge, cleat, and fastener spacing. The wind-design basis, the design pressures by zone from the engineer's ASCE 7 calculation, so a reviewer can see the rating meets or beats the corner-zone pressure where the edge sits in the corner. The shop drawings of every condition: the fascia, the coping, the corners, the joints, the splice plates, the terminations, the scuppers, and the transitions between them. And the fastening schedule for both the cleat and the nailer anchorage.

Then the field QA runs against that approved package, not against memory. The crew installs the gauge that was rated, the cleat that was rated, and the fastener spacing that was rated, especially tightened up in the corner and perimeter zones where the approved drawing calls for it. The most common quiet failure is an edge installed to a looser pattern than the rating was earned with, so it looks right and is not rated. Walk the perimeter against the shop drawing, confirm the cleat is continuous and engaged, confirm the corner fastening matches the corner detail, and document it. The rating only counts if the field built the assembly the rating describes.

Why does roof edge metal blow off?

Roof edge metal blows off because the attachment could not carry the uplift, and the causes are a short, repeating list. Walk enough storm-damaged roofs and you stop being surprised by what you find, because it is the same handful of mistakes every time.

Face-fastened with no continuous cleat is the classic. Screws through the front of the fascia load in withdrawal, the weakest direction, so the wind backs them out and peels the metal. Undersized for the corner zone is next: the edge was rated or built for the field pressure and put up in the corner, where the suction is two to three times higher, so the corner lets go and the failure spreads from there. A weak or poorly anchored nailer is the failure underneath the failure, where the metal and cleat held but the blocking pulled off the deck as a unit. Coping that was not anchored on both faces lifts and folds back over the parapet. And an edge with no ES-1 rating at all, shop-fabricated to look the part with nothing tested behind it, is a gamble that pays off until the design wind actually shows up.

The water failures ride alongside the wind ones. Joints that were lapped and caulked instead of floated on a splice plate split open with thermal movement and leak. Coping back-pitched to the street streaks the wall and saturates it. A scupper or termination flashed loose lets water behind the metal. None of these are exotic. They are the result of treating the edge as trim, installing it by habit, and skipping the rating and the load path. The defense is the same every time: a rated assembly, a continuous cleat into solid anchored blocking, the corner sized for the corner, joints that move, and a submittal you actually built to.

What to document

The edge record is what answers the question after a storm or a leak: was the perimeter rated and built right, or not. A wind claim and a warranty claim both turn on whether the edge met the design wind and was installed to the tested assembly, and the only proof is the documentation made while the work happened. The metal is up and the cleat is hidden once the job is done, so the record is the evidence the edge was right.

Capture it by condition as the work goes: the edge type at each run, the ES-1 rating and test method for the system, the design wind pressure for the zone it sits in, the continuous cleat and its fastening, the nailer size and its anchorage to the structure, the joint type and spacing, the gauge and finish, and the membrane termination detail. Tie the corners out separately, because the corner is the zone that fails and the zone the rating has to cover. Keep the approved shop drawing and the ES-1 report with the closeout, because that is the package a reviewer or a rep reads, and the file a claim is judged against years later.

Common mistakes

• Installing edge metal with no ES-1 rating, shop-fabricated to look the part with nothing tested behind it.
• Face-fastening the fascia or coping with no continuous cleat, loading the screws in withdrawal where wind backs them out.
• Rating or building the corner zone to the field pressure, when the corner sees two to three times the uplift.
• Anchoring the nailer to the deck on a loose pattern that pulls off as a unit under uplift.
• Anchoring coping on only one face, so the cap lifts and folds back over the parapet.
• Lapping and caulking coping joints tight instead of floating them on a splice plate, so they split with thermal movement.
• Running long edge sections with no expansion joints, so the metal buckles in heat and pulls the joints open in cold.
• Back-pitching the coping to the street so it streaks and saturates the wall instead of draining to the roof.
• Dropping below the tested gauge, or pairing dissimilar metals and fasteners that corrode at the laps.
• Installing to a looser fastener spacing than the ES-1 assembly was rated with, so it looks right and is not rated.

Field checklist

Standards and references

The central document is ANSI/SPRI/FM 4435/ES-1, the test standard for edge systems used with low-slope roofing. It sets the RE-1, RE-2, and RE-3 test methods, defines low slope as 2:12 or flatter, and is the standard the code points to for fascia, gravel stops, and coping. The manufacturer's ES-1 test report for the specific system governs, because it states the rated pressure and the tested assembly you have to build to. External gutters fall outside ES-1 and are covered by ANSI/SPRI GT-1.

The code makes ES-1 mandatory. The International Building Code requires low-slope metal edge systems to be designed for the wind loads of its structural chapter and tested to the ES-1 methods, in the roof-assembly provisions commonly cited around Section 1504.5, though the number shifts between cycles, so confirm it against the adopted edition and local amendments. The wind loads themselves come from ASCE 7, which sets the design wind speed, the exposure, and the field, perimeter, and corner zones that drive the higher edge pressures. Confirm the design pressures with the engineer of record.

Around those sit the rest of the framework. FM Global Data Sheet 1-49 covers perimeter flashing and gives FM-rated wind pressures for fascia, coping, and gutters on insured roofs, working with the wall-zone wind design in Data Sheet 1-28, and FM's RoofNAV listings now report tested pressure values rather than older ratings. The NRCA Roofing Manual is the practical reference for edge-metal detailing, nailer blocking, and shop-fabricated edge testing. The membrane manufacturer's published edge details and warranty govern the membrane termination at the edge. Where any of these conflict, the stricter requirement and the project specification control, so confirm every figure here against the actual standards and the adopted code before citing one on a submittal.

Units, terms, and conversions

Edge-metal work uses a specific vocabulary, and the same part reads differently across a shop drawing, an ES-1 report, and a spec, so the terms are worth pinning down.

Wind pressure is given in pounds per square foot (psf) for the face and cap loads and in pounds per linear foot (plf) for membrane restraint, matching the ES-1 test units. Metal thickness is given as gauge for steel, where a smaller gauge number is thicker metal, and in inches or decimals for aluminum. Slope on a coping is a small cross-slope to the roof side. A fascia or drip edge caps an open edge; a coping caps a parapet; a gravel stop holds ballast. A continuous cleat is the hooked strip the hemmed drip locks onto. The nailer is the perimeter wood blocking the edge fastens into. An uplift zone is the field, perimeter, or corner band ASCE 7 uses to set the design pressure.

Edge metal

Formed sheet metal capping the roof perimeter: fascia, coping, drip edge, and gravel stop

Coping

The metal cap over a parapet wall, lapping both faces and draining to the roof side

Continuous cleat

A hooked metal strip fastened to the building that the edge metal's hemmed drip locks over for uplift resistance

ANSI/SPRI ES-1

The national test standard for low-slope roof edge systems, with the RE-1, RE-2, and RE-3 wind tests

Uplift zone

The field, perimeter, or corner band under ASCE 7; the corner sees the highest suction

Nailer

Continuous perimeter wood blocking the edge metal and cleat fasten into, part of the wind load path

Drip hem

The bottom edge of the fascia or coping bent back into a hook that locks over the continuous cleat

Splice plate

A concealed backer with sealant strips under a coping joint that seals it while allowing thermal movement

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