HomeMy WebLinkAbout11162005 BSC Agenda Item 3 City of West University Place*Texas
Memo
To: Building Standards Commission Members
From: Debbie Scarcella,Chief Building Official
Date: November 16,2005
Re: Staff Recommendation for Agenda Item No.3-Structural
Attached is a proposed ordinance amendment concerning the design and construction of the structural
framing elements. The ordinance amendment addresses the design and certification of all structural
framing elements and specifically sets out the criteria by which the certifications may be certified. In
addition,the proposed amendment requires full exterior sheathing of a minimum of 7/16"wood
structural panels;requires the species and grade of all nominal and engineered wood products to be
specified in the plans;requires the length,spacing,and direction of trusses and joists to be specified in
the plans;and prescribes the standard by which all metal truss connectors must be in compliance.
Earlier versions of this proposed amendment included prescriptive requirements for additional elements
of the structures. By adoption of the 2003 International Codes and the local climatic and geographical
design elements table(Section 301.2(1)of the International Residential Code,2003 edition),the intent
of those proposed requirements will be met.
Staff recommends approval and support of this ordinance,and will be working with the City Attorney
to develop the proper certification documents to implement its provisions.
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Draft amendment of the
Standard Technical Codes Schedule
regarding structural framing
and similar elements
revised 11-08-05
Technical Codes Schedule
Adoption. Subject to the amendments and deletions indicated beneath each code, each of the following codes,
including all of its published appendices and attachments, is adopted, ordained and made a part of the Code of
Ordinances of the City and of each chapter where it is referenced, except as otherwise expressly provided.
Procedure for amendments,etc. The procedure for adopting new codes, updated codes, local amendments and
provisions for administration and enforcement of these codes is as follows: (1)proposal by the building official or
other appropriate City official, (2)referral to the Building&Standards Commission, (3)consideration by the
City Council, after giving required meeting notices, and(4)adoption and publication, as required by Article II of
the City Charter.
International Building Code,2003 Ed., International Code Council, Inc.
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5. Structural Elements; Engineering, Etc.
a. Scope Definitions.
(1) The structural elements for the following must meet the criteria in this section, as
applicable:
(i) each new building (and each addition to an existing building)
containing habitable space and having either a gross floor area of
485 square feet or more or a floor higher than four feet; and
(ii) each accessible deck, porch, balcony,walkway and similar
structure with a floor height greater than feet. [Note: Unless
otherwise defined, "height" is measured from the "standard base
level" as provided in the Zoning Ordinance.]
(2) This section does not apply to foundation elements observed and certified under
another section.
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(3) In this section:
"A2LA Lab"means a laboratory accredited by the American Association
for Laboratory Accreditation on the basis of ISO/IEC 17025:1999
("general requirements for the competence of testing and calibration
laboratories").
"RLPE" means a licensed or registered professional engineer of the State
of Texas who is:
(1) listed with the State Board of Professional Engineers in either the
civil or structural branch of engineering (but, from and after May 1,
2006, listing in the structural branch is required);
(2) employed by a registered engineering firm of the State of Texas;
and
(3) covered by professional errors and omissions insurance that: (i)
has limits of at least$250,000 per claim(and at least$500,000 per
year, aggregate) and (ii)has effective dates—including any
retroactive coverage date—that include the entire period when the
person provides services or takes actions regulated by this section.
b. Engineering; Plans &Specifications. Structural elements must be constructed in
accordance with complete plans and specifications prepared, signed and sealed by
a RLPE. The plans and specifications must be prepared specifically for the
structure in question, and they must meet criteria as to scope, content and form
specified by the building official.
c. Certain Requirements.
(1) Framing; Sheathing. All framing must include full exterior sheathing with
structural elements (or blocking) along all joints. The plans must indicate the
type, size and spacing of fasteners. All sheathing must be minimum 7/16"
structural wood panels.
(2) Trusses, Joists, Etc.
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(a) The species and grade of all lumber used for trusses,joists,puffins,
purlin supports or similar elements must be specified in the plans.
(b) The length, spacing and direction of trusses and joists must be
specified in the plans.
(c)Each manufactured wood truss must comply with applicable
requirements of the "National Design Standard For Metal Plate Connected
Wood Truss Construction"published by Truss Plate Institute (TPI), 1-
2000 Ed.
d. Observation & Certification. Structural elements must be professionally observed
and must be certified by an RLPE, as more fully described below:
(1) Observations must:
(i) be performed either by the certifying RLPE or by one or more
persons under that RLPE's direct supervision and control whose
professional qualifications are approved by the RLPE,
(ii) include actual observation of structural elements and attachments
in crawl spaces before they are covered by floors or other
materials,
(iii) Include actual observations of each beam,joist,rafter,truss and
similar element, including each related weld and high-strength
bolt: (i) after all required plumbing, electrical and mechanical
"rough-in"inspections have been passed and all expected
"notching,"boring and similar work has been done, and (ii) before
the item is covered, and
(iv) Be documented in a form and manner approved by the building
official (which may include photographs).
(2) Certifications must:
(i) refer to and be based upon the professional observations required
by this section,
(ii) state that the portions of the work required to be observed comply
with the plans and specifications last approved by the building
official (with any field changes that are ordered by the RLPE,
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reported to the building official and in compliance with applicable
regulations),
(iii) comply with criteria as to form and content as may be specified by
the building official,
(iv) be signed and sealed by the certifying RLPE, and
(v) be filed with the building official.
(3) Certifications may rely in part upon attached certifications by: (i) an A2LA
Lab, as to materials testing, and (ii) an inspector certified by the City of
Houston, as to welds or high-strength bolts (see, also, Section 1704.3.3 of
the IBC).
Before any a beam,joist, rafter, truss, weld, high-strength bolt or similar element
is covered: (i) all required city inspections relating to that element must be passed,
and (ii)the permittee must obtain written acknowledgment from the building
official that the certification for that element was duly filed as required above.
For any given building, there may be more than one certification filed.
After a beam,joist, rafter,truss, weld, high-strength bolt or similar element has
been observed and certified, as provided above, it may not be notched, bored or
structurally altered without: (i) a new or amended permit, if required, and(ii) a
new observation and certification, in accordance with this section.
Certifications,plans, specifications and related items may be kept on file by the
City, for public inspection, for an indefinite period of time.
e. Special Exceptions. The BSC may issue a special exception from any requirement
in subsection"a"through"c," above, but only upon a showing that:
(1) the requirement will not affect life safety or the performance of a structure
(for its estimated useful life); or
(2) an alternate requirement to be imposed by the special exception will
provide equal or better protection for life safety and long-term structural
performance.
In connection with any such special exception,the BSC may require that the
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applicant provide supporting engineering data and opinion, and the BSC may
impose conditions to carry out the purpose and intent of applicable regulations.
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