Recommendations for statewide building code changes in coastal hazard areas Performance

[From the U.S. Government Printing Office, www.gpo.gov]

New York State Department of State
Division of Coastal Resources and Waterfront Revitalization

@Recommendations For Statewide Building Code
Changes In Coastal Hazard Areas

309 Project of Special Merit

VD
IV) Performance Report
'41L to the Office of Ocean and Coastal Resources Management
National Ocean Service
National Oceanic and Atmospheric Administration
U.S. Department of Commerce

June 1994

INTRODUCTION

This is the final report in a series of 4 performance reports
on the progress of activities related to amending the New York
State Uniform Fire Prevention and Building Code (Code) . The
Department of State, Division of Coastal Resources and Waterfront
Revitalization (DCRWR) reviewed standards and recommendations from
FEMA, NOAA, various coastal states, the scientific and engineering
literature and building code organizations to develop the proposed
amendment to the Code. This report presents the revised amendment
by the Department of State, Codes Division, and highlights major
changes that were made to the draft code section contained in
Performance Report No. 3. A copy of the transmittal letter from
the Department of State to the Division of Housing and Community
Renewal (DHCR) for review of the proposed amendment by the Codes
Council is enclosed, along with a brief discussion of the process
DHCR and the Codes Council must go through before the proposed
amendment can be adopted as part of the Code.

DRAFT AMENDMENT REVIEW BY DOS, CODES DIVISION

DCRWR coordinated two reviews of the proposed amendment with
Codes Division personnel in the Department of State. The initial
review of the draft amendment dealt largely with the format to be
used and proper code language. Changes were made to various
sections in an attempt to clarify them and eliminate all
ambiguities and redundancies. The initial review also focused on
which documents should be incorporated as reference standards in
the Code. The final review by Codes Division personnel was
performed to examine some additions to the structural requirements
of the proposed amendment made by DCRWR and to ensure that all
changes recommended in the initial review had been satisfactorily
made.

CHANGES TO THE PROPOSED AMENDMENT

The following changes have been made to the draft code section
contained in Performance Report No. 3:

1. The Coastal Hazard Area Construction Standards section was
changed from section 810 to part 1130 because this section
falls under the category of special requirements.

2. The design loads to which pile foundations may be
subjected are the loads specified in section 803 and the
horizontal water loads specified in Appendix D.8 of the
FEMA Coastal Construction Manual.

3. Pile analysis shall consider the piles in column action
from the bottom of the structure to the stable soil

elevation and shall determine if pile bracing is required
to resist the design loads. Acceptable types of pile
bracing and bracing placement recommendations are also
given.

4. Acceptable materials for piles in coastal hazard areas,
minimum sizes for timber piles, and recommendations for
pile installation are provided in the structural
requirements.

5. Additional recommendations on framing, connecting, and
bracing wood framed structures are provided in the
structural requirements.

6. Hazardous locations 1, 3, 4, 5 and 7 were deleted f rom the
list of hazardous locations for the purposes of glazing
because these locations were not unique to coastal
construction and are already contained in section 715 of
the Code.

7. Specific language to address the plumbing issues was
provided by the Codes Division of the Department of State
and has been included in the proposed amendment.

8. The specific draft language developed by DCRWR to address
mobile homes located in coastal hazard areas has been
deleted. Standards for the construction of mobile homes
shall be in accordance with the requirements of section
1221.1 of the Code. Mobile homes located in coastal
hazard areas shall be located and installed in accordance
with the requirements of part 1223, the structural
requirements of part 1131, and part 1133.

PROCESS OF AMENDING THE STATE FIRE PREVENTION AND BUILDING CODE

Executive Law 377 authorizes the State Fire Prevention and
Building Code Council (Council) to formulate, periodically review
and amend the Code. The Council is part of the Division of Housing
and Community Renewal (DHCR) . DOS has forwarded the proposed final
amendment to DHCR expressing the belief that this amendment will
improve construction standards in coastal hazard areas, thus
reducing the risk to life and property from severe storms. (See
attached transmittal letter.)
Depending on the schedule of the Codes Council, which meets
periodically, it may be some time before the proposed amendment
comes up for review. The Council is a deliberative body and the
review process is likely to involve much discussion and debate of
the key items in the section under consideration. The Council may
require certain portions of the new section be rewritten and
resubmitted. In view of this process, it will probably take more
than a year before the proposed amendment is finally adopted as
part of the Code.

Article 16

Coastal Hazard Area Construction Standards

PART 1130

COASTAL HAZARD AREA CONSTRUCTION STANDARDS

Section 1130.1 Scope. Buildings and structures located within coastal hazard areas, as
defined herein, shall conform with the requirements of this article. Provisions of this article
shall take precedence over less restrictive provisions of this code with respect to buildings and
structures located within coastal hazard areas.

Section 1130.2 Definitions. For the purpose of this part the following shall apply:

(a) Mean Sea Level (MSL) - The tidal datum which is the arithmetic mean of hourly
water level heights observed over a 19 year period by the National Ocean Service.

(b) Base Flood Elevation (BFE) - The peak water elevation in relation to Mean Sea Level
(MSQ expected to be reached during a flood having a one percent chance of being equalled
or exceeded in any given year. The Base Flood Elevation shall be determined from the
FEMA Flood Insurance Rate Map for the coastal area in which the structure is located.

(c) V-Zone - Velocity zone subject to coastal flooding and high velocity waters including
storm wave wash, as shown by the @EMA Flood Insurance Rate Maps. V-zones are located
along the Atlantic Shoreline of New York State, including the shoreline of Long Island Sound
and adjacent bays, and the shoreline of Lake Ontario and Lake Erie.-

(d) Coastal Erosion Hazard Area (CEIM) - Area identified by the New York State
Department of Environmental Conservation under Article 34 of the Environmental
Conservation Law, Coastal Erosion Hazard Area Act, near the shoreline of the Atlantic
Ocean and Great Lakes which has been identified as subject to at least one of the following
hazards: (1) Historical or predicted future trends of long term erosion, (2) erosion expected
to occur during a coastal storm reaching the base flood elevation, or (3) shoreline fluctuations
due to tidal inlets.

(e) Coastal Hazard Area - All areas which are located within the V-zone or the coastal
erosion hazard area.

(f) FEMA - FEMA is the United States Federal Emergency Management Agency. This
agency administers the National Flood Insurance Program and publishes the official flood
insurance rate maps (FIRMS).

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(g) Lowest Floor - The lowest floor of the lowest enclosed area (including basement or
cellar). An unfinished or flood'resistant enclosure, usable solely for parking of vehicles,
building access to storage in an area other than a basement area is not considered a building's
lowest floor; provided:

a. That the walls are substantially impermeable to the passage of water and the
structural components have the capability of resisting hydrostatic and
hydrodynamic loads and effects of buoyancy; or,

b. Construction shall be designed to automatically equalize hydrostatic flood
forces on exterior walls by allowing the entry and exit of flood waters.

PART 1131 STRUCTURAL REQUIR]EWNTS

Section 1131.1 Piling standards. (a) All buildings located in coastal hazard areas shall
be constructed and anchored on pile foundations of sufficient strength to support the design loads
to which they may be subjected including loads specified in section 803 and horizontal water
loads specified in Appendix D.8 of RS 20-3. Piles shall be designed so the pile size and pile
embedment are adequate to support the specified design loads. Pile embedment shall include
consideration of the type of soil, method of pile installation, and decreased resistance capacity
caused by anticipated scour of soil strata surrounding the piling based on local scour data. In
the absence of local scour data, a scour depth of 4.5 feet shall be used for the first row of
structures and 2 feet for inland structures. Spread footings and fill shall not be used for
structural support purposes. Mat or raft foundations which support columns shall not be
permitted where soil investigations indicate that soil material under the mat or raft is subject to
scour or erosion from wave-velocity flow conditions.

(b) All pilings within the coastal hazard area shall have a minimum tip penetration of at least
5 feet below MSL or 16 feet below average original grade, whichever results in the deeper
penetration.

(c) Pile foundation analysis shall include consider-ation of the piles in column action from the
bottom of the structure to the stable soil elevation and shall determine if pile foundation bracing
is required to provide adequate lateral resistance to the specified design loads. Acceptable types
of pile foundation bracing include knee bracing, diagonal bracing, truss bracing, and horizontal
bracing. Knee braces shall be permitted along pile rows parallel and perpendicular to the
shoreline. Knee braces shall be sloped at or near one horizontal to one vertical and shall not
extend more than 3 feet below the BFE. Diagonal braces shall be sloped at or near one
horizontal to one vertical. Diagonal bracing consisting of wood members shall only be placed
along pile rows perpendicular to the shoreline. Diagonal bracing consisting of steel rods or steel
cable shall be permitted in any plane. Truss br-acing systems providing increased later-al

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resistance to pile foundations shall consist of diagonals, struts, and bolted connections and shall
be limited to the same locations as diagonal bracing. All connections for pile foundation bracing
shall be bolted connections. Information on pile foundation bracing is provided in Appendix B
of RS 20-3.

(d) Acceptable materials for piles in coastal hazard areas include wood and reinforced
concrete. The minimum sizes for timber piles shall be a tip diameter of 8 inches for round
timber piles and 8" x 8" for square timber piles. Concrete piles shall be cast of concrete with
a 28 day compressive strength of not less than 5000 psi and shall be reinforced with a minimum
of 4 longitudinal steel bars having an area of not less than I percent nor more than 4 percent of
the gross concrete area.

(e) Piles installed by driving shall be driven by a pile driver or drop hammer that holds the
pile in position through the use of leads while the pile is being driven. A protective driving cap
shall be utilized to transmit energy from the hammer to the pile during the driving process.
Piles installed by jetting shall be designed assuming a loose sand soil condition due to the jetting
operation. Piles shall not be driven closer than 2 feet to each other or to an existing structure.
Piles shall not be jetted closer than 10 feet to an existing structure unless approved by a design
professional. Splicing of foundation piles shall be avoided. Pile splices that are unavoidable
shall be constructed to provide and maintain aligment and position of the component parts of the
pile and to transfer pile loads across the splice.

Section 1131.2 Elevation standards. (a) The lowest structural member excluding piling
and bracing supporting the lowest habitable floor in the coastal hazard area shall be elevated
above the base flood elevation (BFE) plus wave height addition.

(b) The wave height addition is determined by the flood water depth (D) under the building
using the formula: (See Figure 1)

Wave Height Addition = 0.55 X D

Where D = base flood elevation minus lowest finish grade elevation; or other acceptable
methods of wave height determination such as found in "Estimating Wave Heights" (FEMA TD-
3) or the Corps of Engineers "Shore Protection Manual" (SPM).

Section 1131.3 Construction, materials, and methods standards. (a) All construction
and equipment located below the Base Flood Elevation shall be resistant to flood damage.

(b) Construction of solid walls or partitions below the lowest floor shall not be permitted in
coastal hazard areas. Non-supporting breakaway walls are permitted when designed by a
registered design professional in accordance with RS 20-3.

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WAVE HEIGHT ADDITION 0.55 x D

D = FLOOD DEPTH

------------------

MAXIMUM WAVE WAVE 0.55 D
HEIGHT ELEVAT'ION HEIGHT,:
............................................ . ........... .. .... ..............................
BASE FLOOD ELEVATION

Figure I WAVE CONDITIONS ON A PILING SUPPORTED BUILDING

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rO..55 D
... ...................

(c) All construction shall be adequately anchored, connected and braced to prevent uplift,
floatation, collapse, lateral movement or overturning during design storm conditions. Special
attention shall be given to connection between major structural subsystems including but not
limited to piling to floor beam, beam to floor joist, joist to exterior side wall diaphragms and
side wall to roof joist.

(d) Wood frame construction:
(1) All floor beam splices shaU be located directly over the beam supports. Notching of pile
tops shall be limited to the minimum amount required to provide ledge support for the framing
members and the cross section of the pile shall not be reduced below 50 percent by notching.

(2) Floor joists shall be fastened to floor beams with metal joist anchors or wood connectors.
Cross bridging or solid bridging shaH be provided for all floor joists at a maximum spacing of
8 feet on center.

(3) Exterior grade plywood not less than 23/32 inches in thickness shall be used for subflooring
and attic flooring throughout wood framed structures. Plywood shall be fastened to the joists
and beams with annular or spiral thread galvanized nails and a waterproof industrial adhesive.
Required plywood thicknesses and methods of attachment shaH be as specified in RS 25-3.

(4) Exterior grade plywood wall sheathing and approved anchors shall be used to form a
continuous tie between roof framing, wall framing, and floor framing. Wall sheathing shaU be
continuous from the top wall plate to the floor beam or joist. At all locations where the plywood
sheets are not verticaHy continuous, 2 x 4 nailer blocking shaU be provided at all horizontal
joints. Exterior grade plywood wall sheathing shall provide bracing to exterior walls to resist
racking due to lateral loads. Plywood wall bracing shall occur at all comers, and shall cover
the floor joist and header and extend to and cover the top plate of the wall. Bracing shall extend
at least 4 feet in each direction from each comer. AU plywood sheathing shall be attached with
annular or spir-al thread galvanized nails. Required plywood thicknesses and methods of
attachment shall be as specified in RS 25-3.

(5) Conventional rafter and ceiling joist construction shall be installed so the joists provide a
continuous tie across the rafters. Roof rafters and ceiling joists shall be securely fastened at
their intersections and shall be fastened to the wan top plate with metal connectors or wood
connectors.

(6) The design of metal plate connected wood roof trusses shall comply with RS 25-27. Roof
trusses shall be adequately braced and anchored to the wan top plate with metal connectors at
all points of bearing. Roof trusses shall be braced and installed in accordance with RS 25-32.
Design drawings for individual roof trusses shall include bracing and anchoring details and shall
be sealed by a Professional Engineer.

(7) Gable roof framing shall be reinforced by installing 2 x 4 blocking at 2 feet on center
between trusses or rafters for a minimum of 8 feet at each end of the structure.

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(8) Roof sheathing shall be exterior grade plywood or board lumber not less than 15/32 inches
in thickness. Sheathing shall be fastened to supports with screws or annular or spir-al thread
nails. Methods of attachment and required plywood thicknesses shall be as specified in RS 25-3.
All fasteners for roof coverings shall be galvanized -or of corrosion resistant material.

(e) All cantilevers and projecting members shall be anchored and braced to withstand forces
due to the specified design loads.

(f) Construction documents shall show details of foundation support and connection components
used in meeting the requirements of Section 1131.3(c) and shall be sealed by a design
professional.

(g) In the coastal hazard area, all metal connectors and fasteners outside of conditioned spaces
shall be hot dip galvanized steel after fabrication and meet the requirements of RS 20-2.
Exposed metal connectors such as tie down straps on porches, decks, and areas under the
structure shall be minimum of 3/16 inch thick and shall be hot dip galvanized after fabrication
and meet the requirements of RS 20-1 or RS 20-2. Metal connectors of approved equivalent
corrosion resistant material may be accepted. See Table A.

Section 1131.4 Records and certifications. (a) Plans or specifications submitted in
connection with a building permit application shall be sealed by a Professional Engineer and
shall certify that the building is designed in compliance with Section 1131.1.

(b) The construction documents shall be accompanied by a statement bearing the signature of
the registered design professional indicating that the design and proposed methods of
construction are in accordance with all applicable provisions of section 1131.2.

(c) The actual elevation required by Section 1131.2 shall be detennined by a Registered Land
Surveyor or Professional Engineer. The actual elevation of the first floor shall be certified by
a Registered I-and Surveyor or Professional Engineer before construction is continued above the
first floor level.

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TABLE A
CORROSION RESISTANCE

(Applies Only to Structures Located in Coastal Hazard Areas)

OPEN VENTED/ENCLOSED CONDITIONED
(exteriors, porches, (attic, floor trusses, (heated/cooled living
underhouse) enclosed crawl spaces areas)
and stud cavity)

Nails, staples, screws Hot Dip galvanized Hot dip galvanized -----
Nuts, bolts washers, tie Hot Dip galvanized Hot Dip galvanized -----
rods

Steel connection plates & Hot Dip galvanized after Hot Dip galvanized
straps (3/16" minimum fabrication
thickness)

Sheet metal connectors, Stainless Steel or Hot Hot dip galvanized after Hot dip galvanized
wind anchors, joists Dipped galvanized after plate fabrication
hangers, steel joists and fabrication
beams

Truss plates Stainless Steel or Hot Hot dip galvanized after Standard galvanized
Dipped galvanized after fabrication or stainless
fabrication steel within 6'-0" of a
gable louver or soffit
vent. Otherwise in
accordance with TIP-78
of the Truss Plate
Institute

PART 1132 GLAZING

Section 1132.1 Glazing standards. (a) Each light shall bear the manufacturer's label
designating the type and thickness of glass. When approved by the Code Enforcement Official,
labels may be omitted from other than tempered glazing materials providing an affidavit is
furnished by the glazing contractor certifying that each light is glazed in accordance with the
approved plans and specifications.

(b) Each unit of tempered glass shall be permanently identified by the manufacturer. The
identification shall be etched or ceramic fired on the glass and be visible when the unit is glazed.
Tempered spandrel glass is exempted from permanent labeling. This type of glass shaft be
identified with a removable paper label by the manufacturer.

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thinner than nominal 7/32 inch and no longer than 48 inches. When other glass types are used,
design shall be submitted to the Code Enforcement Official for approval. Exposed glass edges
shall be smooth. Wired glass with wire exposed on longitudinal edges shall not be used in
jalousies or louvered windows.

(d) Individual glazed areas in hazardous locations including but not limited to those indicated
in section 1132.1 (e) shall pass the test requirements of RS 20-4, or by comparative test shall
be proven to produce at least equivalent performances.

EXCEPTIONS:
1. Pofished wire glass for use in fire doors, fire windows and view panels in 1-hour or
less fire resistant walls shall comply with RS-6.

2. Approved plastic materials used as glazing in hazardous locations shall comply with
RS-6.

(e) The following shall be considered specific hazardous locations for the purposes of glazing.

1. Glazing in fixed and sliding panels of sliding type doors (patio and mall type).

2. Glazing, operable or inoperable, adjacent to a door in all buildings and within the
same wall plane as the door whose nearest vertical edge is within 12 inches of the door
in a closed position and whose bottom edge is less than 60 inches above the floor or
walkdng surface.

(f) The following products, materials and uses are exempt from the above hazardous locations:

I . Openings in doors through which a 3-inch sphere is unable to pass.

2. Leaded glass panels where no individual piece of glass has an area greater than
30 square inches.

3. Glazing materials used as curved glass panels in revolving doors.

4. Commercial refrigerated cabinet glazed doors.

5. Faceted and decorative glass.

(g) Maximum sizes of single regular (annealed) glass may be determined directly from Table
H. 1132. Maximum sizes of other glass types may be determined by first dividing the wind load
determined in section 803.4 and by the factors in Table 1. 1132. Table H. 1132 is applicable for
rectangular glass firmly supported on all four edges. When approved by the Code Enforcement
Official, alternate means for selecting glass may be used in place of Table 1. 1132 and Table
H. 1132.

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(h) Glass supports such as sash members, glazing stops or glazing clips shall be considered
firm when deflection of the support at design load does not exceed 1/175 of the span. Where
other than firm support on all sides is provided, (three sides, two sides, cantilever, or highly
flexible, for example), detailed shop drawings, specifications and rational analysis and/or test
data assuring safe performance for the specific installation shall be prepared by engineers
experienced in this work and shall be submitted for and receive, if warranted, formal approval
by the Code Enforcement Official.

TABLE 1. 1132
RELATIVE RESISTANCE TO WM LOAD

GLAss TYPE FACTOR'

Laminated' 0.75

Wired 0.5

Heat Strengthened 2.0
Fully Tempered 4.0
Insulating glass' 2 panes 1.7
- 3 panes 2.55
Pattemed' 1.0

Sandblasted' 0.4

Regular (annealed) 1.0

Wind pressure determined from section 803.4 should be divided by this factor for use with
Table 11. 1132.

' Applies when two plies are identical in thickness and type; use total glass thickness, not
thickness of one ply.

Applies when each glass pane is the same thickness and type; use thickness of one pane.

4 Use minimum glass thickness, i.e., measured at the thinnest part of the pattern; interpolation
of Table 11. 1132 may be required.

Factor varies depending upon depth and severity of sand blasting; value shown is minimum.

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PART 1133 UTELrIIES

Section 1133.1 Utility connections. (a) Water supply and drainage piping for buildings
or structures located in coastal hazard areas shall be designed to minimize infiltration
and damage by flood waters. Above ground piping shall be securely fastened to sides of interior
piles or piers away from the ocean front or be located within a protective floodproof enclosure
not more than 2' wide unless designed by a Professional Engineer or Architect.

(b) All floor and wall penetrations for plumbing, mechanical and electrical systems shall be made
water tight to prevent flood water seepage through spaces between the penetration and wall
construction materials.

(c) Sanitary sewer systems that have openings below the base flood elevation shall be provided
with shutoff valves or closure devices to prevent back-water flow during conditions of flooding.

PART 1134 MOBILE HOMES

Section 1134.1 Mobile home requirements. Mobile homes located within the coastal
hazard area shall be located and installed in accordance with the requirements of pail 1223, the
structural requirements of part 1131, and part 1133 except Part 1131.3(d).

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WIND LOAD C14ART

Design Wind Load (kPa)

0.6 0.0 1.0 1@5 .0 2.5 3.0 40 5.0 6.0 0.0
300 1 T ---- T- I - -- 2S.0
250-

-20
200-

io.
100-
+ 8.0
80-
Cr 6.0E
Y@. 60
ca 5.0
cri
so-
4.0
V) 40
(A
co
3.0
E
2.5E
E 25 :3 i.
X 2.0E
cc x
20 CU

1.5

1.0
10

6
10 15 20 .30 40 50 60 ISO 200

Design Wind Load (psf)
Design Factor = 2.5
Chart Applies for Width-to-Length Ratios from 1:5 to 1:1

Based on Minimum Glass Thickness Allowed In Federal Specifleat(on
D D-G-451 D

TABLE 11.1132 WM LOAD CHART

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STRUCTURAL REFERENCE STANDARDS (to be added)

RS No. Issued by Title

RS 20 OCE Flood Proofing Regulations
EP-11652314, June 1992

RS 20-1 ASTM Standard Specification for Zinc Hot Dip
Galvanized Coating on Iron and Steel Products
A123-89A

RS 20-2 ASTM Standard Specification for Zinc Coating
(Hot Dip) on Iron and Steel Hardware
A153-87

RS 20-3 FEMA Design and Construction Manual for Residential
Buildings in Coastal High Hazard Areas
(Coastal Construction Manual)
FEMA-55, February, 1986

RS 20-4 FEMA/CPSC Consumer Product Safety Commission
Architectural Glazing Materials, Federal Register
16-77 CFR Part 1201 Category II

RS 25-32 TPI Bracing Wood Trusses
Commentary and Recommendations for Handling,
Instilling and Bracing Metal Plate Connected
Wood Trusses
BWT-76

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NOAA COASTAL SERVICES CTR LIBRARY

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