Staff Analysis for
Declaratory Statement Request DS2014-002
January 16, 2014
Issue: DS2014-002. The Petitioner, Gulf Coast Supply and Manufacturing, LLC (Ray Bowen), seeks a Declaratory Statement on Chapter 15, sections 1503.1, 1503.2.1 and 1507.4 and Tables 1503.2 and 1507.4.3(1) of the 2010 Florida Building Code, Building.
Petitioner in DS2014-002 seeks clarification
of the following questions:
Question 1: Does Table 1503.2 set forth the minimum thickness requirements, flashings
used on metal roof systems, even though thinner metal roofing panels are
acceptable per Table 1507.4.3(1)?
Question
2: Do what we in the industry call “Trims” (eave drips, wall trims, ridge
caps, preformed valleys, etc.) qualify as flashings, seeing they are always
installed at the locations listed in 1503.2.1
Background:
Situation:
Gulf Coast Supply and Manufacturing, LLC is a leading manufacturer of
metal roofing systems in Florida, with over 30 different product approval
including FPA #1165.25. Gulf Coast
Supply “Manufacturer” has four manufacturing locations in Florida, and sells
directly to hundreds of state certified roofers from Key West to Jacksonville
to the Gulf Coast and west to Panama City. The Manufacturer supplies hundreds
of roofing packages per week, primarily for residential applications. The
roofing packages contain metal roofing panels (which are tested as part of the
approval), and flashings (which are not tested as part of the approval.
The Manufacturer has a question about the requirements of Chapter 15 of
the Florida Building Code. The Code requires that the minimum
thickness of metal roofing panels be in accordance with table
1507.4.3(1), which requires Aluminum Zinc Coated Steel Panels to be at least
.013” thick. However, there is nothing
in section 1507.4 that specifies minimum thicknesses for flashings that are used on
metal roofs. There is, however, a table in the beginning
of Chapter 15 that addresses the subject (Table 1503.2), and according to that
table the minimum thickness for Aluminum Zinc Coated Steel Flashings is .0179”.
Specifically: “The Code requires that the minimum thickness of metal
roofing panels be in accordance with table 1507.4.3(1), which
requires Aluminum Zinc Coated Steel panels to be at least .013” thick. However, there is nothing in section 1507.4
that specifies minimum thicknesses for flashings that are used on metal roofs.
There is, however, a table in the beginning of Chapter 15 that addresses
the subject (Table 1503.2), and according to that table the minimum thickness
for Aluminum Zinc Coated Steel Flashings is .0179”.”
Relevant Code Sections
SECTION 1503 WEATHER PROTECTION
1503.2 Flashing. Flashing
shall be installed in such a manner so as to prevent moisture entering the wall
and roof through joints in copings, through moisture-permeable materials and at
intersections with parapet walls and other penetrations through the roof plane.
1503.2.1 Locations. Flashing
shall be installed at wall and roof intersections, at gutters, wherever there
is a change in roof slope or direction and around roof openings. Where flashing
is of metal, the metal shall be corrosion resistant with a thickness not less
than provided in Table 1503.2.
Exception: This requirement does
not apply to hip and ridge junctions.
TABLE 1503.2
METAL FLASHING MATERIAL
|
Material |
MINIMUM THICKNESS (INCHES) |
GAGE |
WEIGHT (LBS PER SQ FT) |
|
Copper |
|
|
1 (16oz) |
|
Aluminum |
0.024 |
|
|
|
Stainless Steel |
|
28 |
|
|
Galvanized Steel |
0.0179 |
26 (zinc coated G90) |
|
|
Aluminum Zinc Coated Steel |
0.0179 |
26 (AZ50 Alum Zinc) |
|
|
Zinc Alloy |
1.027 |
|
|
|
Lead |
|
|
2.5 (40 oz) |
|
Painted Terne |
-- |
|
1.25 (20 oz) |
1507.4
1507.4.3(1)
1507.4 Metal roof panels. The
installation of metal roof panels shall comply with the provisions of this
section.
1507.4.1 Deck requirements. Metal roof
panel roof coverings shall be applied to a solid or closely fitted deck, except
where the roof covering is specifically designed to be applied to spaced
supports.
TABLE 1507.4.3(1)
METAL ROOF COVERINGS
|
ROOF COVERING TYPE |
STANDARD |
STANDARD APPLICATION RATE/THICKNESS |
|
Aluminum |
ASTM B 209 |
0.024 inch minimum thickness for roll-formed panels and 0.019 inch
minimum thickness for press-formed shingles |
|
Aluminum-zinc coated steel |
ASTM A 792 |
0.013 inch minimum thinkness, AZ 50 (coated minium application rate) |
|
Cold-rolled copper |
ASTM B 370 |
Minimum 16oz/sq.ft. and 12 oz./sq.ft. high yield copper for
metal-sheet roof covering systems: 12 oz/sq.ft. for preformed metal shingle
systems. |
|
Galvanized steel |
ASTM 653 |
0.013 inch minimum thickness, G-90 zinc-coated. |
|
Hard lead |
|
2 lbs./sq.ft. |
|
Lead-coated copper |
ASTM B 101 |
|
|
Prepainted steel |
ASTM A 755 |
|
|
Soft lead |
|
3 lbs./sq.ft. |
|
Stainless Steel |
ASTM A 240 |
300 Series Alloys |
|
Steel |
ASTM A 924/ ASTM A 924M |
|
|
Terne and Terne-coated stainless |
|
Terne coating of 40 lbs. per double base box, filed painted where
applicable n accordance with manufacturer’s installation instructions. |
|
Zinc: |
|
0.027 inch minimum thickness; 99.995% electrolytic high grade zinc
with alloy additives of copper (3.08% - 0.20%), titanium (0.07% - 0.12%) and
aluminum (0.015%) |
For SI: 1 ounce per square foot = 1.0026 kg/m2, 1 pound per
square foot = 4.882 kg/m2, 1 inch = 25.4 mm, 1 pound = 0.454 kg.
a.For Group U buildings, the minimum coating thickness for ASTM A 653
galvanize steel roofing shall be G-60.
TRIMS
FBC, Building
Section: 802.1
TRIM. Picture
molds, chair rails, baseboards, handrails, door and window frames and similar
decorative or protective materials used in fixed applications.
FLASHING. The roofing component
used to seal roofing systems, where the system is interrupted or terminated.
Staff Analysis: Based on the above facts and circumstances,
staff provides the following answers to proponent’s questions:
Question #1:
To the question #1: Does Table 1503.2 set forth the
minimum thickness requirements flashings used on metal roof systems, even
though thinner metal roofing panels are acceptable per Table 1507.4(3)?
Answer: Yes. Table 1503.2 is specific to the type and gage
of flashing that it is be utilized and does not differentiate based on types of
roof covering to be used.
Question #2:
To the question #2: Do what we in the industry call
“Trims” (eve drips, wall trims, ridge caps, preformed valleys, etc.) qualify as
flashings, seeing they are always installed at the locations listed in
1503.2.1?
Answer: Yes. As long as the items in question are covered
within scope of section 1503.2 of the 2010 Florida Building Code, Building.