Sheet Metal Flashing and Trim | Building Arhcitecture

1. SCOPE……………………………………………………………………..2. REFERENCES 3. GENERAL
3.1 Scope of Sheet Metal Work …………………………………….3.2 Performance Requirements 3.3 Submittals 3.4 Quality Assurance………………………………………………….3.5 Project Conditions 4. PRODUCTS
4.1 Manufacturers ………………………………………………………4.2 Materials
4.3 Concealed Through-wall Sheet Metal Flashing Material4.4 Reglets ………………………………………………………………..4.5 Miscellaneous Materials and Accessories 4.6 Fabrication, General 4.7 Sheet Metal Fabrications ……………………………………….4.8 Aluminum Finishes 4.9 Coil-coated Galvanized Steel Sheet Finish 5. EXECUTION……………………………………………………………………5.1 Examination 8
5.2 Installation 9
5.3 Cleaning and Protection …………………………………………

1. Scope
This specification covers flashing and trim for architectural sheet metal work as shown on the project
drawings and detailed in 3.1.
2. References
Reference is made in this specification to the following documents. The latest issues, amendments, and
supplements to these documents shall apply unless otherwise indicated.
Aluminum Association (AA)
Designation System for Aluminum Finishes
American Architectural Manufacturers Association (AAMA)
605.2 Specification for High Performance Organic Coatings on Architectural Aluminum Extrusions
and Panels
606.1 Specification and Inspection Methods for Integral Color Anodic Finishes for Architectural Aluminum
607.1 Specification and Inspection Methods for Clear Anodic Finishes for Architectural Aluminum
608.1 Specification and Inspection Methods for Electrolytically Deposited Color Anodic Finishes for
Architectural Aluminum
American Society for Testing of Materials (ASTM)
A 167 Specification for Stainless and Heat-Resistant Chromium-Nickel Steel Plate, Sheet, and Strip
A 653 Specification for Steel Sheet, Zinc-coated (Galvanized) or Zinc-Iron Alloy-Coated (Galvannealed) by
the Hot Dip Process
B 32 Specification for Solder Metal
B 209 Specification for Aluminum and Aluminum-Alloy Sheet and Plate
B 221 Specification for Aluminum and Aluminum-Alloy Extruded Bars, Rods, Wire, Profiles, and Tubes
D 4586 Specification for Asphalt Roof Cement, Asbestos Free
Sheet Metal and Air Conditioning Contractors National Association (SMACNA)
Architectural Sheet Metal Manual
Steel Structures Painting Council (SSPC)
SSPC-Paint 12 1991 – Cold Applied Asphaltic Mastic (Extra Thick Film)
3. General
3.1 Scope of Sheet Metal Work
Sheet metal work shall consist of:
a. Roof-drainage systems
b. Exposed trim, gravel stops, and fasciae
c. Copings
d. Metal flashing
e. Reglets
f. Roof expansion-joint covers
3.2 Performance Requirements
Installed sheet metal flashing and trim shall withstand wind loads, structural movement, thermally induced
movement, and exposure to weather without failing.

3.3 Submittals
The following shall be submitted for SABIC approval:
a. Product data, with manufacturer’s material and finish data, installation instructions, and general
recommendations for each specified flashing material and fabricated product
b. Shop drawings of each item specified, showing layout, profiles, methods of joining, and
anchorage details
c. Samples of sheet metal flashing, trim, and accessory items, in the specified finish. Where finish
involves normal color and texture variations, samples, 200 mm square shall be included, in sets
composed of 2 or more units showing the full range of variations expected
3.4 Quality Assurance
3.4.1 Installer Qualifications. Contractor shall engage an experienced installer who has completed sheet
metal flashing and trim work similar in material, design, and extent to that indicated for the project, and with
a record of successful in-service performance.
3.4.2 Mockups. Prior to installing sheet metal flashing and trim, mockups shall be constructed to verify
selections made, based on sample submittals, and to demonstrate aesthetic effects and qualities of
materials and execution. Mockups shall be constructed to also comply with the following requirements,
using materials indicated on drawings for final unit of work:
a. Mockups shall be located on-site in the location and of the size indicated or, if not indicated, as
directed by architect/engineer or SABIC
b. Architect/engineer or SABIC shall be notified, one week in advance of the dates and times when
mockups will be constructed
c. Proposed range of aesthetic effects and workmanship shall be demonstrated
d. Mockups shall be constructed for the following type of sheet metal flashing and trim:
(i) Gutters and downspouts
(ii) Scuppers
(iii) Exposed trim, gravel stops, and fasciae
(iv) Copings
e. SABIC’s approval of mockups shall be obtained before start of final unit of work
f. Mockups shall be retained and maintained during construction in an undisturbed condition as a
standard for judging the completed work
3.5 Project Conditions
Work of this specification shall be coordinated with interfacing and adjoining work for proper sequencing of
each installation. The completed work shall ensure best possible weather resistance, durability of work,
and protection of materials and finishes.
4. Products
4.1 Manufacturers
Subject to compliance with the requirements of this specification, manufacturer’s standard products shall
be provided, complying with the following material finishes and physical properties. Where manufacturers
are listed under a specific category, substitution will be considered by SABIC in accordance with provisions
of contract.

4.2 Materials
One of the following materials shall be selected, as indicated on the drawings.
4.2.1 Aluminum, which shall be the alloy and temper recommended by aluminum producer and finisher
for type of use and finish indicated, and with not less than the strength and durability of the following alloy
and temper:
a. Mill-Finish Aluminum Sheet. ASTM B 209, 3003-H14 (alloy number followed by temper number).
b. Anodized Aluminum Sheet. ASTM B 209, 5005-H14.
c. Factory-Painted Aluminum Sheet. ASTM B 209, 3003-H14.
d. Extruded Aluminum: ASTM B 221, alloy 6063 T52.
4.2.2 Stainless-steel sheet, which shall be ASTM A 167, Type 304, soft annealed, with No. 2D finish,
except where harder temper is required for forming or performance.
4.2.3 Galvanized steel sheet, which shall be ASTM A 653, G 90, hot-dip galvanized steel sheet with 0.20
percent copper, mill phosphatized where indicated for painting.
4.3 Concealed Through-wall Sheet Metal Flashing Material
Fabrication shall consist of the following:
a. Stainless steel, 0.4 mm thick
b. Through-wall metal flashings embedded in masonry shall be fabricated with ribs formed in
dovetail pattern at 75 mm intervals along length of flashing to provide a 3-way integral mortar bond
and weep-hole drainage
4.4 Reglets
4.4.1 General. Units of type, material, and profile indicated on project drawings, formed to provide secure
interlocking of separate reglet and counterflashing pieces, and compatible with flashing indicated on
project drawings.
4.4.2 Surface-Mounted Type. Slotted holes shall be provided for fastening to substrate, with neoprene or
other suitable weatherproofing washers, and with channel for sealant at top edge.
4.4.3 Stucco Type. Upturned fastening flange and extension leg shall be provided to match thickness of
applied finish materials.
4.4.4 Concrete Type. Temporary closure tape shall be provided to keep reglet free of concrete materials,
also special fasteners for attaching reglet to concrete forms, and guides to ensure alignment of reglet
section ends.
4.4.5 Masonry Type. Offset top flange shall be provided for embedment in masonry mortar joint.
4.4.6 Flexible Flashing Retainer. Resilient plastic or rubber accessory shall be provided to secure flexible
flashing in reglet where clearance does not permit use of standard metal counterflashing, or where
drawings show reglet without metal counterflashing.
4.4.7 Counterflashing Wind-Restraint Clips. Clips shall be installed before counterflashing is provided, to
prevent wind uplift of the counterflashing lower edge. Clips shall be made from one of the following
material as indicated on drawings:
a. Stainless steel, 0.5 mm thick
b. Aluminum, 0.6 mm thick
c. Galvanized steel, 0.55 mm thick

4.5 Miscellaneous Materials and Accessories
The following miscellaneous materials and accessories shall be provided:
a. Solder for Galvanized Steel. Conforming to ASTM B 32, Grade Sn 50, used with rosin flux
b. Solder for Stainless Steel. Conforming to ASTM B 32, Grade Sn 60, and to be used with an acid
flux of type recommended by stainless steel sheet manufacturer. A noncorrosive rosin flux shall be
used over tinned surfaces.
c. Fasteners. These shall be the same metal as sheet metal flashing, or other noncorrosive metal
as recommended by sheet metal manufacturer. Finish of exposed heads shall be matched with
material being fastened.
d. Asphalt Mastic. This shall be SSPC Paint 12, solvent-type asphalt mastic, nominally free of sulfur
and containing no asbestos fibers, compounded for 0.4 mm dry film thickness per coat
e. Mastic Sealant. This shall be polyisobutylene; a nonhardening, nonskinning, nondrying,
nonmigrating sealant
f. Adhesives and Sealants. These shall be of a type recommended by flashing sheet metal
manufacturer for waterproof and weather-resistant seaming and adhesive application of flashing sheet
metal
g. Metal Accessories. Sheet metal clips, straps, anchoring devices, and similar accessory units as
required for installation of work shall be provided, matching or compatible with material being installed;
noncorrosive; and of the size and thickness required for performance
h. Gutter Screen. This shall be 6 mm hardware cloth installed in sheet metal frames. Screen and
frame shall be fabricated of same basic material as gutters and downspouts.
i. Roofing Cement. Conforming to ASTM D 4586, Type I, asbestos free, and asphalt based
4.6 Fabrication, General
4.6.1 Sheet metal flashing and trim shall be fabricated to comply with the recommendations of SMACNA’s
‘Architectural Sheet Metal Manual’ that apply to the design, dimensions, metal, and other characteristics of
the item indicated.
4.6.2 The fabrication of sheet metal flashing and trim shall comply with details shown. Flashing and trim
shall fit substrates and result in waterproof and weather-resistant performance once installed. Shapes and
dimensions of surfaces to be covered shall be verified before fabricating sheet metal.
4.6.3 Exposed sheet metal work shall be formed without excessive oil canning, buckling, or tool marks,
and shall be true to line and levels indicated, with exposed edges folded back to form hems.
4.6.4 Nonmoving seams in sheet metal shall be fabricated with flat-lock seams. Tin edges to be seamed,
shall be formed and soldered.
4.6.5 Nonmoving seams in aluminum shall be fabricated with flat-lock seams.
4.6.6 Thermal movement joints shall be spaced at maximum of 3 m, with no joints allowed within 610 mm
of corners or intersections. Where lapped or bayonet-type expansion provisions cannot be used, or would
not be sufficiently weatherproof and waterproof, expansion joints shall be formed of intermeshing hooked
flanges, not less than 25 mm deep, and filled with mastic sealant, concealed within joints.
4.6.7 Nonexpansion, but movable joints shall be formed in metal to accommodate elastomeric sealant, to
comply with SMACNA standards.
4.6.8 Fasteners and expansion provisions shall be concealed where possible. Exposed fasteners shall not
be allowed on faces of sheet metal exposed to public view.
4.6.9 Cleats and attachment devices shall be fabricated from same material as sheet metal component
being anchored, or from compatible, noncorrosive metal recommended by sheet metal manufacturer. Size
shall be as recommended by SMACNA Architectural Sheet Steel Manual or sheet metal manufacturer for
the application, but not less than thickness of metal being secured.

4.7 Sheet Metal Fabrications
Sheet metal items shall be fabricated in thickness or weight required to comply with performance
requirements, but not less than that listed below for each application and metal. Material shall be used asshown on the drawings.
a. Gutters with Girth
(i) Factory painted aluminum, 1.0 mm thick or
(ii) Factory painted galvanized steel, 0.7 mm thick
b. Downspouts
(i) Factory painted aluminum, 0.7 mm thick
(ii) Factory painted galvanized steel, 0.7 mm thick
c. Conductor Heads
(i) Factory painted aluminum, 0.8 mm thick
(ii) Factory galvanized steel, 0.7 mm thick
d. Splash Pans: Factory painted aluminum, 1.0 mm thick
e. Roof-Drain Flashing
(i) Aluminum, 0.8 mm thick
(ii) Galvanized steel, 0.7 mm thick
f. Scuppers
(i) Factory painted aluminum, 0.8 mm thick
(ii) Factory painted galvanized steel, 0.7 mm thick
g. Exposed Trim, Gravel Stops, and Fasciae
(i) Factory painted aluminum, 1.2 mm thick
(ii) Factory painted galvanized steel, 1.0 mm thick
h. Copings
(i) Factory painted aluminum, 1.2 mm thick
(ii) Factory painted galvanized steel, 1.0 mm thick
i. Base Flashing
(i) Factory painted aluminum, 1.0 mm thick
(ii) Factory painted galvanized steel, 0.8 mm thick
j. Counterflashing
(i) Factory painted aluminum, 0.8 mm thick
(ii) Factory painted galvanized steel, 0.6 mm thick
k. Flashing Receivers
(i) Factory painted aluminum, 0.8 mm thick
(ii) Factory painted galvanized steel, 0.6 mm thick
l. Drip Edges
(i) Factory painted aluminum, 0.8 mm thick

(ii) Factory painted galvanized steel, 0.6 mm thick
m. Eave Flashing
(i) Factory painted aluminum, 0.8 mm thick
(ii) Factory painted galvanized steel, 0.6 mm thick
n. Equipment Support Flashing: Galvanized steel, 0.7 mm thick
o. Roof-Penetration Flashing: Galvanized steel, 0.7 mm thick
p. Roof Expansion-Joint Cover
(i) Aluminum, 1.0 mm thick
(ii) Galvanized steel, 0.7 mm thick
q. Roof-to-Wall Expansion-Joint Cover:
(i) Aluminum, 1.2 mm thick
(ii) Galvanized steel, 0.85 mm thick
4.8 Aluminum Finishes
Aluminum finishes shall comply with AA’s ‘Designation System for Aluminum Finishes’ for finish
designations and application recommendations. See drawings for aluminum finishes and colors. Finishes
shall be one of the following:
a. Class I, Clear Anodic Finish. AA C22A41 (chemical finish: etched, medium matte; anodic coating:
architectural class I, clear coating 0.018 mm or thicker) complying with AAMA 607.1.
b. Class I, Color Anodic Finish. AA C22A42/A44 (chemical finish: etched, medium matte; anodic
coating: architectural class I, integrally colored or electrolytically deposited color coating 0.018 mm or
thicker) complying with AAMA 606.1 or AAMA 608.1.
4.9 Coil-coated Galvanized Steel Sheet Finish
4.9.1 A high-performance organic coating finish shall be applied using the coil-coating process on
galvanized steel sheet, as recommended by coating manufacturers and applicator.
4.9.2 The fluoropolymer 2 coat coating system shall be used. This shall be manufacturer’s standard
2 coat, thermocured system composed of specially formulated inhibitive primer and fluoropolymer color
topcoat, containing not less than 70 percent polyvinylidene fluoride resin by weight, complying with
AAMA 605.2.
4.9.3 Color and gloss shall be selected by architect/engineer or SABIC from manufacturer’s range.
4.9.4 Subject to compliance with the requirements of this specification fluoropolymer coating systems
containing resins shall be provided, produced by one of the following manufacturers, or SABIC approved
equal:
a. Ausimont USA, Inc. (Hylar 5000)
b. Elf Atochem North America, Inc. (Kynar 500)
5. Execution
5.1 Examination
Substrates and the conditions under which sheet metal flashing and trim are to be installed shall be
examined, to verify that work may properly commence. Installation shall not start until unsatisfactory
conditions have been corrected.

5.2 Installation
5.2.1 General. Unless otherwise indicated on drawings, sheet metal flashing and trim shall be installed to
comply with performance requirements, manufacturer’s installation instructions, and SMACNA’s
‘Architectural Sheet Metal Manual’.
a. Units of work shall be anchored securely in place by methods indicated in 5.2.1, providing for
thermal expansion of metal units.
b. Fasteners shall be concealed where possible, and units shall be set true to line and level as
indicated on drawings.
c. Work with laps, joints, and seams shall be permanently watertight and weatherproof.
5.2.2 Exposed sheet metal work shall be installed without excessive oil canning, buckling, and tool marks,
and shall be true to line and levels indicated, with exposed edges folded back to form hems. Sheet metal
flashing and trim shall be installed to fit substrates, and shall result in waterproof and weather-resistant
performance.
5.2.3 Expansion joints shall be provided for thermal expansion of exposed sheet metal work, and shall be
spaced at maximum of 3 m with no joints allowed within 610 mm of corners or intersections.
5.2.4 Surfaces to be soldered shall be cleaned by removing oils and foreign matter.
5.2.5 Nonexpansion, but movable joints shall be filled with sealant, and metal shall be formed to
completely conceal sealant. Joint adhesive shall be used for nonmoving joints, and shall be specified not
to be soldered.
5.2.6 Nonmoving aluminum seams shall be sealed with epoxy seam sealer. Joints shall be rivetted for
additional strength.
5.2.7 Metal shall be separated from noncompatible metal or corrosive substrates by coating concealed
surfaces at locations of contact, using asphalt mastic or other permanent separation as recommended by
manufacturer.
5.2.8 Reglets shall be installed to receive counterflashing according to the following requirements:
a. Where reglets are shown in concrete, they shall be furnished for installation as shown on
drawings
b. Where reglets are shown in masonry, they shall be furnished for installation as shown on
drawings
5.2.9 Installation of counterflashings shall be coordinated with installation of assemblies to be protected
by counterflashing. Counterflashings shall be installed in reglets or receivers. They shall be secured in a
waterproof manner by means of snap-in installation and sealant, lead wedges and sealant, interlocking
folded seam, or blind rivets and sealant. Counterflashing joints shall have a lap of a minimum of 50 mm
and shall be bedded with sealant.
5.2.10 Roof. Drainage items fabricated from sheet metal shall be installed with straps, adhesives, and
anchors recommended by SMACNA’s ‘Architectural Sheet Metal Manual’ or the item manufacturer, to
drain roof in the most efficient manner. Roof-drain flashing installation shall be coordinated with
roof-drainage system installation. Flashing and sheet metal items shall be coordinated for steep-sloped
roofs with roofing installation.
5.2.11 Equipment support flashing installation shall be coordinated with roofing and equipment
installation. Flashing shall be welded or sealed to equipment support member.
5.2.12 Roof-penetration flashing installation shall be coordinated with roofing and installation of items
penetrating roof. Flashing shall be installed as follows:
a. Lead flashing shall be turned down inside vent piping, being careful not to block vent piping with
flashing

b. Flashing shall be sealed and clamped to pipes penetrating roof, except for lead flashing on vent
piping
5.2.13 Splash pans shall be installed where downspouts discharge on low-sloped roofs, unless otherwise
shown on drawings. They shall be set in roof cement or sealant compatible with roofing membrane.
5.2.14 Continuous gutter screens shall be installed on gutters, with noncorrosive fasteners, and arranged
as hinged units to swing open for cleaning gutters.
5.3 Cleaning and Protection
5.3.1 Exposed metal surfaces shall be cleaned by removing substances that might cause corrosion of
metal, or deterioration of finishes.
5.3.2 Final protection shall be provided and maintained during construction, to ensure that sheet metal
flashing and trim work remain without damage or deterioration, other than that caused by natural
weathering at the time of substantial completion.

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