Office of the City Manager
INFORMATION CALENDAR
July11, 2006
To:
Honorable Mayor and
Members of the City Council
From:
Phil Kamlarz, City Manager
Submitted by: Dan Marks, Director, Planning and Development
Subject:
Guidelines For Seismic Strengthening Work Qualifying For The Transfer
Tax Reduction
INTRODUCTION
As of October 1, 2006, the Building Official is releasing a set of guidelines to clarify
the scope of work required to qualify for the real estate transfer tax seismic reduction.
Berkeley Municipal Code (BMC) Section 7.52.060.K.2. provides for a rebate of up to
0.5 % of the sales price (one-third of the 1.5% transfer tax). The new guidelines
include provision for use of Plan Set A designed for use without individual
engineering for one or two story houses with cripple walls of less than four feet.
The purpose of the guidelines is to ensure that work to seismically strengthen
buildings is effective and provides true value for the costs incurred by the owner and
for the revenue foregone by the City of Berkeley. Work to repair or replace
substandard foundations in compliance with conventional construction standards,
securing of chimneys and stacks, removal of unreinforced masonry chimneys, and/or
anchoring of water heaters is eligible without engineering; other seismic
strengthening work must either comply with Plan Set A or be engineered to meet
applicable standards.
CURRENT SITUATION AND ITS EFFECTS
Currently, there are no local or state adopted code standards for wood frame structures
of less than five units governing work that is commonly called “voluntary retrofit”.
This work should more appropriately be termed “seismic strengthening” since the
entire house is very seldom completely retrofitted. Completing even the three major
elements of the retrofit of the cripple wall area, consisting of bolting mud sills to the
foundation, installing plywood shear walls, and connecting floor joists to the cripple
wall, is not always done. Lacking state adopted standards, nearly all California cities
essentially apply a “do-no-harm standard” in reviewing and approving such proposed
work.
2180 Milvia Street, Berkeley, CA 94704 ● Tel: (510) 981-7000 ● TDD: (510) 981-6903 ● Fax: (510) 981-7099
E-Mail: manager@ci.berkeley.ca.us Website: http://www.ci.berkeley.ca.us/manager
Guidelines For Seismic Strengthening Work
July 11, 2006
Because of an informed citizenry and the well-used transfer tax rebate for seismic
strengthening, it has been estimated that over 40% of single family housing in
Berkeley has had some form of such work done. However, a recent survey of single
family homes that have had seismic strengthening work in four cities along the
Hayward fault was reported on by the Contra Costa Times on March 5, 2006. It found
that only about a third of these buildings were likely to withstand a major quake.
Common problems were that one of the three major retrofit elements of the cripple
wall area was not completed or was done improperly. An Association of Bay Area
Governments (ABAG) study reached a similar conclusion.
Thus, some owners may be getting a false sense of security about work performed,
and the City may not be getting full value for its investment of tax monies.
BACKGROUND
Berkeley, has pioneered in the field of seismic retrofit, adopting:
• Standards for the voluntary retrofit of larger residential and other special types
of structures as part of the last building code update.
• Standards for the mandatory retrofit of unreinforced masonry buildings
• Standards for the engineering assessment of seismic weaknesses of “soft-story”
apartment buildings.
• A rebate of up to one-third of the 1.5% of the transfer tax for “seismic
strengthening” of any residential building and of mixed-use buildings with at
least two residential units.
There has been concern among building officials, engineers, and others in the “retrofit
community” that such work on smaller wood frame structures was not accomplishing
effective strengthening because of a lack of standards for evaluating plans. As
described below, this concern has led to staff efforts in several venues to address the
issue: through Bay Area chapters of the International Code Council (ICC), the City of
Berkeley, and the Association of Bay Area Governments (ABAG).
The East Bay, Monterey, and Peninsula chapters of the ICC established a working
group to update a prescriptive plan set that has been used by San Leandro to provide
guidance for homeowners. Called Plan Set A, it provides construction details and
instructions for bolting, shear wall installation, and connecting the floor to the cripple
wall, and a plan grid for showing the foundation plan. The Plan Set applies to woodframe structures with two or fewer residential units that are two stories or less in
height and have a crawl space with cripple walls of four feet or less. The three
chapters of the ICC as well as the Northern California chapter of the Earthquake
Engineering Research Institute, the Structural Engineers Association of Northern
California and ABAG endorsed the Plan Set.
2118 Milvia Street, Suite 300, Berkeley, CA 94704 Tel: 510.981-7400 TDD: 510.981.6903 Fax: 510.981-7490
E-mail: planning@ci.berkeley.ca.us
P. 2
Guidelines For Seismic Strengthening Work
July 11, 2006
In Berkeley, the Building Official convened a work group consisting of staff, three
members of the Disaster Council and a member of the Seismic Technical Advisory
Group. Together, the group had participation of a contractor, a homeowner, a former
building official, and an engineer who is an international expert on seismic mitigation.
This group reviewed the current transfer tax law and various standards for judging
seismic strengthening work. Initially, the group was examining a formal legislative
process for adopting standards and amendments. However, after consulting with the
City Attorney, it was decided that the Building Official promulgating guidelines was
the simplest and most straightforward way of improving this work.
Additional public outreach included:
• A discussion held with the Disaster Council at their meeting of February 9,
2006, where they approved of the use of the guidelines and provided comments
on a draft.
• A meeting in December 2005, to which all contractors who had building
permits issued for such work in the last three years were invited to review and
comment on an early draft, with about twenty-one attending.
• A follow-up meeting on May 18, 2006, for those contractors who expressed
interest in attending to review and comment on the last draft and the use of
Plan Set A.
In response to suggestions from some contractors, the guidelines now allow for the
use of alternate details to Plan Set A. In addition, several sessions with city plan
checking staff resulted in significant clarification of the language to improve its
actual usability. The resulting guidelines are attached for your review and comment
tonight.
Staff is also working with the ABAG Earthquake Hazard Outreach Review Committee
on a proposal to the California Earthquake Authority (CEA) related to single-family home retrofit
issues and pilot programs. Elements of the program would strengthen ABAG’s program
of training of contractors, homeowners, and building department staff and expand the
applicability of Plan Set A. Concerns about the lack of standards for wood frame
retrofits has also prompted members of the Bay Area engineering community and the
Applied Technology Council to seek a CEA grant to address additional questions
about this issue.
Staff presented an information report on June 1, 2006, to the Housing Advisory
Commission (HAC) on the guidelines. The HAC members commented favorably on
establishing effective standards for seismic strengthening and wanted more outreach
to owners. As a result, staff has put back the roll out date for the guidelines to
October 1, 2006, in order to develop the requested outreach.
2118 Milvia Street, Suite 300, Berkeley, CA 94704 Tel: 510.981-7400 TDD: 510.981.6903 Fax: 510.981-7490
E-mail: planning@ci.berkeley.ca.us
P. 3
Guidelines For Seismic Strengthening Work
July 11, 2006
POSSIBLE FUTURE ACTION
Future actions will include developing and implementing outreach, including making
copies of Plan Set A available and preparation of a brochure for homeowners. The
next step is to meet with the Board of Realtors to discuss the guidelines and what
other outreach for owners is needed. Possible outreach efforts could include holding
workshops on the guidelines and on practical tips of how to do the work as well as
developing a permanent display in the Permit Service Center.
Continued and enhanced training for inspectors and plan checkers will be conducted.
A review of field inspections will be conducted to determine if more time is needed in
carrying out inspections, as one of the key problems is that work is sometimes not
performed precisely and thus fails to provide the full protection of the design.
FISCAL IMPACTS OF POSSIBLE FUTURE ACTION
About $2,000 will be needed to prepare and print the brochures and Plan Set copies
(budget code: 833-8601-463-9960). In addition to some administrative staff costs,
there will be some minor costs in time and paying for staff to attend special training.
Increased time for inspections or increased numbers of inspections for seismic
strengthening, if determined to be needed, may also add some staff costs.
CONTACT PERSON
Joan MacQuarrie, Building Official, Planning and Development, 510 981-7441
Dan Lambert, Senior Management Analyst, Planning and Development, 510 981-7406
Attachments:
1: Guidelines for Seismic Strengthening Work Qualifying for the Transfer Tax Reduction
2: Text of BMC 7.52.060, Seismic Transfer Tax Reduction
2118 Milvia Street, Suite 300, Berkeley, CA 94704 Tel: 510.981-7400 TDD: 510.981.6903 Fax: 510.981-7490
E-mail: planning@ci.berkeley.ca.us
P. 4
Attachment 1
Planning & Development Department
Building & Safety Division
Guidelines for Seismic Strengthening Work Qualifying
for the Transfer Tax Reduction
A. Introduction and Purpose: These guidelines clarify the scope of work required by
applicable codes to qualify for the real estate transfer tax seismic reduction. Berkeley
Municipal Code (BMC) Section 7.52.060.K.2. provides up to 0.5 % of the sales price
can be rebated to the owner on a dollar-for dollar basis for expenditures for seismic
strengthening. The purpose of the guidelines is to ensure that work to seismically
strengthen buildings is effective and provides true value for the costs incurred by the
owner and for the revenue foregone by the City of Berkeley.
B. Requirements: The following criteria shall be met for work to be eligible for the
transfer tax seismic reduction:
.
1. The purpose of the work shall be to improve the seismic resistance of the
existing structure only and not to facilitate additions or other improvements to
the building.
2. The work shall be for a building that is exclusively residential OR of mixeduse with 2 or more residential units.
3. The owner or contractor shall obtain a building permit, complete the permitted
work and obtain an approved final inspection from the Building and Safety
Division, as well as submitting the required transfer tax application to the
Finance Department for approval of the rebate.
4. The work shall reasonably addresses seismic vulnerabilities so that it does
NOT:
a. Reduce the structural integrity of the existing structure,
b. Create a condition where loads are not distributed equally, OR
c. Interfere with any subsequent phase of completing an overall retrofit.
p. 1 of 3
5. The scope of work shall consist of ONE OR MORE of the following:
a. Repair or replacement of substandard foundations in compliance with
conventional construction standards or designed by a licensed or
registered design professional, securing of chimneys and stacks,
removal of unreinforced masonry chimneys, and/or anchoring of water
heaters;
b. Work that is designed by a licensed or registered design professional
that meets the submittal requirements of section 106.3 of the California
Building Code, AND meets or exceeds one of the following:
• 75% of the horizontal force levels as established by Chapter 16 of the
current California Building Code; OR
• 100% of the horizontal force levels as established by BMC Section
19.28.240 (attached) for retrofits not triggered by other requirements;
OR
• 100% of the force levels as established by Chapter 23 of the 1976
Uniform Building Code.
c. For buildings on the City’s Inventory of Potentially Hazardous Buildings,
corrective work required by BMC chapter 19.38.
d. Other work demonstrated to the Building Official to increase substantially
the capability of these structures to withstand damage in an earthquake.
e. As provided in Section C, work for certain buildings of one or two units
that complies with Plan Set A or alternate details. Plan Set A provides
instructions and details designed to be useable for self-help retrofits.
C. To use Plan Set A, the building shall be a wood-frame structure with two or fewer
residential units that is two stories or less in height and has a crawl space with cripple
walls of four feet or less. The scope of work shall consist of EITHER of the following:
1. Work that fully complies with the International Code Council Tri-Chapter’s Plan
Set A; OR
2. Work in compliance with an approved alternate detail to 1a, 1b, 2a or 2b of plan
Set A. To be approved as an alternate detail, the permit application shall
include the following information:
a. The applicable Plan Set A information and detailed drawings adequate
to permit plan review of the proposed alternate connection; AND
b. Calculations provided by a licensed design professional that
demonstrate capacity not less than that which would be required by Plan
Set A, where the required allowable stress design capacity shall be
permitted to be determined by multiplying the required bracing length by
380 pounds per linear foot.
D. Eligible plans to be stamped: When approved, a seismic strengthening plan
meeting these regulations shall be clearly stamped: “When final inspection is
completed, this work is eligible for the Transfer Tax Reduction provided in BMC
7.52.060 but does not constitute a complete seismic retrofit.” Only work under plans
so stamped qualifies as “seismically retrofitting” work eligible for the Transfer Tax
Seismic Reduction.
p. 2 of 3
Chapter 19.28 BERKELEY BUILDING CODE*
Section 19.28.240 General.
CBC 3401. General.
1. Buildings in existence at the time of the adoption of this code may have their existing use or
occupancy continued, if such use or occupancy was legal at the time of the adoption of this code, provided
such continued use is not dangerous to life.
Any change in the use or occupancy of any existing building or structure shall comply with the
provisions of Sections 109 and 3405 of this code.
For existing buildings see Appendix Chapter 34, Division III. See also Section 101.3.
2. When seismic retrofit provisions are not triggered by other requirements of this code, the following
standards are hereby adopted and made a part of this chapter as though fully set forth herein, subject to the
modifications thereto which are set forth in this chapter for voluntary seismic retrofit: Chapter 2,
Earthquake Hazard Reduction in Existing Reinforced Concrete and Reinforced Masonry Wall Buildings
with Flexible Diaphragms, Chapter 4, Earthquake Hazard Reduction in Existing Wood-frame Residential
Buildings with Soft, Weak or Open-front Walls and Chapter 5, Earthquake Hazard Reduction in Existing
Concrete Buildings and Concrete with Masonry Infill Buildings from Guidelines for Seismic Retrofit of
Existing Buildings, 2001 Edition, published by the International Conference of Building.
For a comprehensive code and guidelines on the treatment of existing buildings, see also Guidelines for
Rehabilitation of Existing Buildings. (Ord. 6727-NS § 1, 2003)
p. 3 of 3
Attachment 2
Seismic Reduction section of the Transfer Tax Ordinance
Section 7.52.060 Exceptions.
K. 1. Up to one-third of the tax imposed by this chapter shall be reduced, on a dollar
for dollar basis, for all expenses incurred on or after October 17, 1989 to "seismically
retrofit" either any structure which is used exclusively for residential purposes, or any
mixed use structure which contains two or more dwelling units.
2. The term "seismically retrofit" within the meaning of this chapter means any of the
following:
a. That work which is needed and directly related to make the structure capable
of withstanding lateral loads equivalent to the force levels defined by Chapter 23 of the
1976 Uniform Building Code;
b. Replacement or repair of foundations; replacement or repair of rotted mud
sills; bracing of basement or pony walls; bolting of mud sills to standard foundations;
installation of shear walls; anchoring of water heaters; and/or securing of chimneys,
stacks or water heaters;
c. Corrective work on buildings which fit the criteria in subsection K.1, which
are listed on the City of Berkeley inventory of potentially hazardous, unreinforced
masonry buildings when such work is necessary to meet City standards or requirements
applicable to such buildings;
d. Any other work found by the building official to substantially increase the
capability of those structures, specified in subsection K.1, to withstand destruction or
damage in the event of an earthquake.