28 TAC §5.4008
The Commissioner of Insurance adopts amendments to §5.4008,
concerning building code specifications in the plan of operation of the Texas
Windstorm Insurance Association (Association or TWIA). The amendments to §5.4008
are adopted without changes to the text published in the April 21, 2000 issue
of the
Texas Register
(25 TexReg 3411) and
will not be republished.
The purpose of the Association is to provide windstorm and hail insurance
coverage to residents in designated catastrophe areas who are unable to obtain
such coverage in the voluntary market. The Association's plan of operation
specifies in §5.4008 the applicable building code standards to qualify
for coverage from the Association for structures located in designated catastrophe
areas which were constructed, repaired, or to which additions are made on
and after September 1, 1998, the effective date of the Building Code for Windstorm
Resistant Construction (the code). The amended section adopts by reference
amendments to the Building Code for Windstorm Resistant Construction. The
adopted amendments are necessary to make editorial and clarifying changes
that make the code more user-friendly and easier to use. The adopted amendments
are a result of recommendations by the Building Code Advisory Committee on
Specifications and Maintenance to expand the available use of the code in
the designated catastrophe areas. Article 21.49, §6C, Insurance Code
requires the Commissioner to appoint a Building Code Advisory Committee on
Specifications and Maintenance (advisory committee) to advise and make recommendations
to the Commissioner on building specifications in the TWIA plan of operation
for structures to be eligible for windstorm and hail insurance through the
TWIA. The advisory committee met on February 3, 2000 to consider the proposed
recommendations presented by the department staff and voted to recommend certain
building code changes to the Commissioner for his consideration. The advisory
committee's recommended changes were submitted to the Commissioner and those
recommendations were considered at a public hearing on May 11, 2000, Docket
No. 2446, where they were adopted by the Commissioner.
Amended §5.4008 adopts by reference the following amendments to the
code:
A. Section 100, General Requirements: Editorial changes are made in this
section to remove the reference to the wind load provisions of ASCE 7-95.
The prescriptive requirements within the Code and the wind pressures specified
in this section are based on ASCE 7-93. The reference to ASCE 7-95 promotes
confusion.
B. Section 200, Basic Definitions, Assumptions, and Limitations of the
Prescriptive Code.
1. 207, Limitations on the Prescriptive Code. Information presented in
the building limitations tables is to be expanded so that the tables are easier
to use. A clarification is provided to indicate that the span and spacing
limitations for floor systems apply to all types of floor framing members.
C. Section 300, Prescriptive Requirements, Area Inland of the Dividing
Line.
1. 301, Foundations. A clarification provides guidance for anchor bolt
embedment along a raised curb. Tables have been added to provide shear and
uplift capacities for alternative anchors to be determined based on the uplift
and shear load of the default inch diameter anchor bolt. For the selection
of alternative anchors, tables are included to tabulate the appropriate uplift
load to use depending on the building type and wall height. A clarification
is provided in the text, in the fastening schedule and in an illustration
to indicate the proper placement of fasteners for attaching a ledger strip
to a beam where the ledger strip provides support for floor joists in the
construction of a piling or pier and beam foundation. For pier and beam construction,
a table is added to provide options for beam sizes. Text is included to emphasize
that a standard 90-degree hook shall be provided in the footing of the pier
as shown in the existing figure in the appendix. A clarification is added
to indicate the proper placement of reinforcement in the footings of piers.
2. 303, Wood Stud Wall Framing. A clarification is provided to indicate
that the table for uplift loads at gable endwalls applies to one-, two- and
three-story structures. An editorial change is provided to clarify that the
spacers between the lumber used for headers can be wood structural panels
and are not limited to the use of plywood only. A separate header table is
added for headers constructed with Southern Pine lumber. A reference to header
requirements for interior loadbearing walls is removed. Editorial changes
are added to clarify the application of the garage door header tables and
to expand options for the selection of glued-laminated beams. A correction
is made to framing around garage door openings regarding the uplift capacity
of anchor bolts used to transfer uplift loads to the foundation. An editorial
change is provided to clarify that only one holddown connector is required
at each building corner, unless otherwise specified in the Code. Another editorial
change clarifies that standard inch anchor bolts may be used to anchor holddown
connectors to the foundation, if the required capacity of the holddown is
less than the tensile capacity of the anchor bolt embedded in concrete. A
table has also been included to provide capacity values for both the inch
and inch anchor bolts for use with holddown connectors. An editorial change
is provided to renumber and relocate an illustration relating to shear transfer.
4. 305, Ceiling Framing. A clarification is added regarding the construction
of the ceiling diaphragm and gable endwall framing. A figure is revised to
clarify that sheathing must be applied to the wall when installing a brick
veneer.
5. 306, Roof Framing. A clarification is provided to indicate that the
dimensions of the truss shall not exceed the limitations specified in Section
207. Guidance is provided for determining the anchorage of wall studs when
roof trusses are used. A table is provided to specify the maximum allowable
anchorage for the bearing points of a truss. Additional text is added to clarify
the attachment of roof sheathing along the perimeter of the roof and at gable
endwalls.
6. 307, Roof Coverings. ASTM standards are added to stipulate the minimum
requirements for underlayment. A revision to the fastening requirements for
the double layer application of felt is included so that the fastening pattern
will be the same as required for attachment of a single layer application.
An option is included which provides guidance for the attachment of underlayment
for shingles that pass Underwriters Laboratories (UL) Standard 997 and are
rated at wind speeds which meet the Code's minimum fastest mile wind speed
requirement of 95 mph.
7. 311, Miscellaneous Construction. An editorial change was made to correct
a conflict between the text and a table relating to the attachment of the
beam to post connection in post frame construction. A clarification is provided
for the attachment of purlins to roof framing in post frame construction.
Fastener requirements have been added for the attachment of corrugated metal
siding or wood structural panel siding in post frame construction. The fastener
requirements have been revised for the attachment of a corrugated metal roof
to purlins or a solid deck in post frame construction. The supported overhangs
and covered porches section is revised to make the section easier to read
and to understand. Guidance is provided for the attachment of overhang roof
framing members to the main structure and to provide a table for uplift capacities
for bolts connecting beams to posts. A clarification is also provided to specify
the measurement of posts supporting beams used in overhangs and porches. A
clarification is provided to address the construction of ceiling framing in
portable and temporary buildings. A new section is added to provide an option
for the construction of a detached garage which can not be constructed in
accordance with Section 303.
8. 312, Reroofing a Wood Shingle or Shake Roof. A clarification is provided
to address the application of wood structural panels over space boards.
9. 313, Additions, Renovations, and Repairs. A new section is added to
address the connection of rafters from an addition to the roof framing of
an existing structure. A new section is added to address the connection of
the wall framing for an addition to an existing structure.
D. Section 400, Prescriptive Requirements, Area Seaward of Established
Dividing Line.
1. 401, Foundations. A clarification provides guidance for anchor bolt
embedment along a raised curb. Tables have been added to provide shear and
uplift capacities for alternative anchors to be determined based on the uplift
and shear load of the default inch diameter anchor bolt. For the selection
of alternative anchors, tables are included to tabulate the appropriate uplift
load to use depending on the building type and wall height. A clarification
is provided in the text, in the fastening schedule and in an illustration
to indicate the proper placement of fasteners for attaching a ledger strip
to a beam where the ledger strip provides support for floor joists in the
construction of a piling or pier and beam foundation. For pier and beam construction,
a table is added to provide options for beam sizes. Text is included to emphasize
that a standard 90-degree hook shall be provided in the footing of the pier
as shown in the existing figure in the appendix. A clarification is added
to indicate the proper placement of reinforcement in the footings of piers.
2. 402, Floor Framing. An editorial change is provided to correct two values
in one of the span tables for floor joists.
3. 403, Wood Stud Wall Framing. A clarification is provided to indicate
that the table for uplift loads at gable endwalls applies to one-, two- and
three-story structures. An editorial change is provided to clarify that the
spacers between the lumber used for headers can be wood structural panels
and are not limited to the use of plywood only. A separate header table is
added for headers constructed with Southern Pine lumber. A reference to header
requirements for interior loadbearing walls is removed. Editorial changes
are added to clarify the application of the garage door header tables and
to expand options for the selection of glued-laminated beams. A correction
is made to framing around garage door openings regarding the uplift capacity
of anchor bolts used to transfer uplift loads to the foundation. An editorial
change is provided to clarify that only one holddown connector is required
at each building corner, unless otherwise specified in the Code. Another editorial
change clarifies that standard inch anchor bolts may be used to anchor holddown
connectors to the foundation, if the required capacity of the holddown is
less than the tensile capacity of the anchor bolt embedded in concrete. A
table has also been included to provide capacity values for both the inch
and inch anchor bolts for use with holddown connectors. An editorial change
is provided to renumber and relocate an illustration relating to shear transfer.
4. 405, Ceiling Framing. A clarification is added regarding the construction
of the ceiling diaphragm and gable endwall framing. A figure is revised to
clarify that sheathing must be applied to the wall when installing a brick
veneer.
5. 406, Roof Framing. A clarification is provided to indicate that the
dimensions of the truss shall not exceed the limitations specified in Section
207. Guidance is provided for determining the anchorage of wall studs when
roof trusses are used. A table is provided to specify the maximum allowable
anchorage for the bearing points of a truss. Additional text is added to clarify
the attachment of roof sheathing along the perimeter of the roof and at gable
endwalls.
6. 407, Roof Coverings. ASTM standards are added to stipulate the minimum
requirements for underlayment. A revision to the fastening requirements for
the double layer application of felt is included so that the fastening pattern
will be the same as that required for attachment of a single layer application.
An option is included which provides guidance for the attachment of underlayment
for shingles that pass (UL) Standard 997 and are rated at wind speeds which
meet the Code's minimum fastest mile wind speed requirement of 100 mph.
7. 411, Miscellaneous Construction. An editorial change is made to correct
a conflict between the text and a table relating to the attachment of the
beam to post connection in post frame construction. A clarification is provided
for the attachment of purlins to roof framing in post frame construction.
Requirements for fasteners are added for the attachment of corrugated metal
siding or wood structural panel siding in post frame construction. The fastener
requirements have been revised for the attachment of a corrugated metal roof
to purlins or a solid deck in post frame construction. The supported overhangs
and covered porches section is revised to make the section easier to read
and to understand. Guidance is provided for the attachment of overhang roof
framing members to the main structure and to provide a table for uplift capacities
for bolts connecting beams to posts. A clarification is also provided to specify
the measurement of posts supporting beams used in overhangs and porches. A
clarification is provided to address the construction of ceiling framing in
portable and temporary buildings. A new section is added to provide an option
for the construction of a detached garage which can not be constructed in
accordance with Section 403.
8. 412, Reroofing a Wood Shingle or Shake Roof. A clarification is provided
to address the application of wood structural panels over space boards.
9. 413, Additions, Renovations, and Repairs. A new section is added to
address the connection of rafters from an addition to the roof framing of
an existing structure. A new section is added to address the connection of
the wall framing for an addition to an existing structure.
E. Appendices.
1. Windstorm Offices. Updated telephone numbers and addresses of the Texas
Department of Insurance's windstorm field offices are added to this appendix.
2. TDI Standard TDI 1-98. An editorial change has been made to define porosity.
3. Fastening Schedule. An editorial change has been made regarding the
fasteners required for securing spaced boards to roof framing and for the
attachment of wood structural panels to spaced boards.
Comment: A commenter supports the adoption of changes to §5.4008 incorporating
revisions to the coastal building code. The commenter says that proposed changes
will make the code more user-friendly and allow for alternative methods of
construction.
Agency Response: The department agrees and appreciates the comments.
For: Texas Association of Builders.
The amendments are adopted pursuant to the Insurance Code Article
21.49 and §36.001. Article 21.49, §6A specifies building code requirements
and approval or inspection procedures for windstorm and hail insurance through
the Association. Article 21.49, §6C requires the Commissioner to appoint
a Building Code Advisory Committee on Specifications and Maintenance to advise
and make recommendations to the Commissioner on building specifications and
maintenance in the Association's plan of operation for structures to be eligible
for windstorm and hail insurance through the Association. Article 21.49, §5(c)
provides that the Commissioner of Insurance by rule shall adopt the Association's
plan of operation with the advice of the Association's board of directors.
Insurance Code §36.001 authorizes the Commissioner of Insurance to adopt
rules and regulations, which must be for general and uniform application,
for the conduct and execution of the duties and function of the Texas Department
of Insurance only as authorized by statute.
This agency hereby certifies that the adoption has been reviewed
by legal counsel and found to be a valid exercise of the agency's legal authority.
Filed with the Office of
the Secretary of State on June 16, 2000.
TRD-200004213
Lynda Nesenholtz
General Counsel and Chief Clerk
Texas Department of Insurance
Effective date: July 6, 2000
Proposal publication date: April 21, 2000
For further information, please call: (512) 463-6327