HomeMy WebLinkAbout02152005 BSC Agenda Item 1 _
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Draft amendment of the
Standard Codes Schedule
regarding foundations
2-16-05 Note: Base draft includes revisions through 11-29-04; additional revisions
reviewed and approved by BSC 2-16-05 are marked in the text.
Delete the existing paragraph 3 under "International Building Code"and insert
the following:
3. The foundation for each new building(and each new addition to a building)All
6. ; - ••• -• :- containing habitable space (as defined in the IBC)(-or
Square feet or mole, must meet the criteria in this section, as applicable. 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) (unless waived by the BSC as provided in"h"below) 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.
"RLGE"means a person who is:
(1) either: (a) a registered professional geoscientist of the State of
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Texas, or(b) a licensed or registered professional engineer who is
listed with the State Board of Professional Engineers in a relevant
branch of engineering(civil, structural or geological) and
employed by a registered engineering firm of the State of Texas;
and
(2) - ••• - ' - • 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.
a. Engineering. Foundations must be constructed in accordance with complete plans
and specifications prepared, signed and sealed(with a mmmaily-impressed-scal
and manual signatures)by a RLPE. The plans and specifications must be prepared
specifically for the site of the work, and they must meet criteria as to scope,
content and form specified by the building official. If there are existing trees
(either to remain or to be removed)within 20 feet of a foundation,that-cot:Ad
affcct a foundation, the RLPE must acknowledge, in writing,Lertify that the trees
have been taken into account in the preparation of the plans and specifications.
b. Geotechnical Report. The plans and specifications for each foundation must be
based on a written geotechnical report prepared, signed and sealed by a RLGE.
The report must cover all testing and site evaluation, and all must meet all
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applicable criteria in"Recommended Practice for Geotechnical Explorations and
Reports"published by the Structural Committee of the Foundation Performance
Association,Houston, Texas (Document#FPA-SC-04-0,Rev#0, 11 April 2001,
issued for website publishing), a copy of which is on file in the City Secretary's
office.
Partial exception: If the basic type of foundation is"structural slab with
void space and deep foundations"or"structural floor with crawl space and
deep foundations,"as described below, the testing, evaluation and report
may be limited to a determination of the appropriate depth for the deep
foundations,but thcy the deep foundation components must meet the other
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applicable-criteria applicable to them
The minimum depth of borings is 20 feet in all cases. All tests and other
laboratory work must be performed by an A2LA Lab.
c. Foundation Performance Standard. For each foundation, the RLPE must certify
that the plans and specifications were prepared to achieve a soil-caused foundation
movement potential of one inch or less, and that the RLPE used the estimated
depth of the active zone and at least two of the following methods to prepare the
plans and specifications:
(1) Potential vertical rise(PVR)determined in accordance with Test Method
Tex-124-E,Rev. January 1, 1978/December 1982, Texas State Department
of Highways and Public Transportation, Materials and Test Division,
"Method for Determining the Potential Vertical Rise,PVR"(a copy of
which is on file in the office of the City Secretary). For this purpose,the
"dry"moisture condition(from which little shrinkage is experienced,but
where volumetric swell potential is greatest) shall be used for each sample
and test.
(2) Swell tests performed in accordance with ASTM D4546-03, "Standard
Test Methods for One-Dimensional Swell or Settlement Potential of
Cohesive Soils"as last revised prior to June 1, 2004.
(3) Suction and hydrometer swell tests performed in accordance with ASTM
D5298-03 "Standard Test Method for Measurement of Soil Potential
(Suction)Using Filter Paper"and ASTM D6836-02 "Standard Test
Methods for Determination of the Soil Water Characteristic Curve for
Desorption Using a Hanging Column, Pressure Extractor, Chilled Mirror
Hygrometer, and/or Centrifuge,"as such methods were last revised prior to
June 1, 2004.
(Partial exception: If the basic type of foundation is "structural slab with void
space and deep foundations"or"structural floor with crawl space and deep
foundations,"as described below,neither a PVR determination nor a swell,
suction or hydrometer test is required.)
d. Foundations, Basic Types. Each foundation must be of an approved basic type.
Approved basic types are listed below. In this list,types of foundations are
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defined and described in"Foundation Design Options For Residential and Other
Low-Rise Buildings on Expansive Soils"published by the Structural Committee
of the Foundation Performance Association,Houston,Texas(Document#FPA-
SC-0l-0,Rev#0, 30 Jun 04, marked"For Website Publishing"), a copy of which
is on file in the City Secretary's office("FDO").
(1) Structural slab with void space and deep foundations.
(2) Structural floor with crawl space and deep foundations.
(3) Stiffened structural slab with deep foundations.
(4) Stiffened non-structural slab with deep foundations.
(5) Grade-supported stiffened structural slab.
(6) Gradc-supported stiffened non-structural slab.
(7) Gra - -bliffcuctl,Ialb of (appivvcd-fvi
.• , : • .' • . - .: .
(6) Mixed-depth system for all new building construction.
(7) Mixed-depth system for building additions with deep foundations.
(8) Another type approved by special exception issued by the BSC. See"h,"
below.
e. Foundations, Deep Support Components. Deep support components must be of
an approved type. Approved types are listed below. In this list,types of deep
support components are defined and described in FDO.
(1) Drilled and underreamed concrete piers.
(2) Drilled straight-shaft concrete piers.
(3) Auger-cast concrete piles.
(4) Another type approved by special exception issued by the BSC. See"h,"
below.
f. Foundations, reinforcement. Reinforcement for each foundation must be of an
approved type. Approved types are listed below. In this list,types of
reinforcement are defined and described in FDO.
(1) Deformed bar reinforcing.
(2) .. - : - . ..' - : . .. : • • • : - : • ..' :' : --.
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habitable spat ).
(3) Another type approved by special exception issued by the BSC. See"h,"
below.
g. Foundations, Observation & Certification. Each foundation 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 (any such
person may be an RLGE, with respect to geophysical matters),
(ii) include actual measurement of piers, fill, compaction,
reinforcement, forms, materials, dimensions, structural elements,
.. , . , attachments, etc. before the work is
covered or concrete is placed(Note: dimensions of an underground
element may be measured or estimated from the forms,boring or
cavity for the element, before pouring or filling),
(iii) be performed continuously during placement of concrete and any
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(iv) be documented in a form and manner approved by the building
official(which may include photographs).
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(2) Certifications must:
(i) refer to and be based upon the professional observations required
by this section,
(ii) state that the work complies with the plans and specifications last
approved by the building official (with any field changes that are
ordered by the RLPE and reported to the building official and that
comply with applicable regulations),
(iii) - ; - , - ... -• . - - .. -.q •
(iv) comply with criteria as to form and content as may be specified by
the building official,
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(iv) be signed and sealed by the certifying RLPE, and
(vi) be filed with the building official.
(3) Certifications may:
(i) rely in part upon an attached certification by a RLGE, as to
geophysical matters, and
(ii) rely in part upon an attached certification by an A2LA Lab, as to
materials testing.
Before framing or other work commences atop a foundation(and before the
foundation is otherwise covered),the permittee must obtain written
acknowledgment from the building official that the certification for the foundation
was duly filed as required above. Certifications,plans, specifications and related
items may be kept on file by the City, for public inspection, for an indefinite
period of time.
h. Special Exceptions. The BSC may issue a special exception from any requirement
in subsection"a"through"g,"above, but only upon a showing that:
(1) the requirement will not affect life safety or the performance of a structure
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.
However: (runless the basic type of foundation is "structural slab with void space
and dee• foundations"or"structural floor with crawl s.ace and dee•
foundations,"as described in this section,the BSC may not issue a special
exce•tion waivin• an re•uirement for an RLPE ur RLGE to have •rofessional
errors and omissions insurance in whole or in •art- and ii the BSC ma not
waive any requirement for an RLGE to have such insurance. In connection with
any such special exception,the BSC may require that the 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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Amend paragraph 4 as follows:
4. All concrete piers, footings and foundations must be cured for at least 72 hours before any
significant load is placed on them.
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