[Federal Register Volume 75, Number 115 (Wednesday, June 16, 2010)]
[Proposed Rules]
[Pages 34064-34074]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2010-14277]
[[Page 34064]]
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DEPARTMENT OF HOUSING AND URBAN DEVELOPMENT
24 CFR Part 3280
[Docket No. FR-5222-P-01]
RIN 2502-A172
Manufactured Home Construction and Safety Standards, Test
Procedures for Roof Trusses
AGENCY: Office of the Assistant Secretary for Housing--Federal Housing
Commissioner, HUD.
ACTION: Proposed rule.
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SUMMARY: This proposed rule would amend the Federal Manufactured Home
Construction and Safety Standards by adopting proposals made by the
Manufactured Home Consensus Committee (MHCC), as modified by HUD. The
National Manufactured Housing Construction and Safety Standards Act of
1974 requires HUD to publish in the Federal Register any proposed
revised Manufactured Home Construction and Safety Standard submitted by
MHCC. Changes to the existing roof truss testing procedures were part
of the first group of MHCC proposals submitted to HUD in 2003 to revise
various aspects of the standards. However, in response to public
comments on the proposed rule, including those submitted by MHCC, HUD
returned the proposal on roof truss testing to MHCC for further
consideration.
After further consideration, MHCC has submitted an amended version
of its 2003 proposal on roof truss testing to HUD. HUD is in agreement
with the majority of MHCC's current recommendations on roof truss
testing. This proposed rule contains the recommendations on which HUD
and MHCC agree. This proposed rule also includes HUD's modifications to
the MHCC proposal, together with HUD's reasons for not accepting those
particular revisions proposed by the MHCC.
DATES: Comment Due Date: August 16, 2010.
ADDRESSES: Interested persons are invited to submit comments regarding
this rule to the Regulations Division, Office of General Counsel, 451
7th Street, SW., Room 10276, Department of Housing and Urban
Development, Washington, DC 20410-0500. Communications must refer to
the above docket number and title. There are two methods for submitting
public comments. All submissions must refer to the above docket number
and title.
1. Submission of Comments by Mail. Comments may be submitted by
mail to the Regulations Division, Office of General Counsel, Department
of Housing and Urban Development, 451 7th Street, SW., Room 10276,
Washington, DC 20410-0500.
2. Electronic Submission of Comments. Interested persons may submit
comments electronically through the Federal eRulemaking Portal at
http://www.regulations.gov. HUD strongly encourages commenters to
submit comments electronically. Electronic submission of comments
allows the commenter maximum time to prepare and submit a comment,
ensures timely receipt by HUD, and enables HUD to make them immediately
available to the public. Comments submitted electronically through the
http://www.regulations.gov Web site can be viewed by other commenters
and interested members of the public. Commenters should follow the
instructions provided on that site to submit comments electronically.
Note: To receive consideration as public comments, comments must
be submitted through one of the two methods specified above. Again,
all submissions must refer to the docket number and title of the
rule.
No Facsimile Comments. Facsimile (FAX) comments are not acceptable.
Public Inspection of Public Comments. All properly submitted
comments and communications submitted to HUD will be available for
public inspection and copying between 8 a.m. and 5 p.m. weekdays at the
above address. Due to security measures at the HUD Headquarters
building, an advance appointment to review the public comments must be
scheduled by calling the Regulations Division at 202-708-3055 (this is
not a toll-free number). Individuals with speech or hearing impairments
may access this number through TTY by calling the Federal Information
Relay Service at 800-877-8339. Copies of all comments submitted are
available for inspection and downloading at http://www.regulations.gov.
FOR FURTHER INFORMATION CONTACT: The Office of Regulatory Affairs and
Manufactured Housing, Office of Housing, Department of Housing and
Urban Development, 451 7th Street, SW., Room 9162, Washington, DC
20410-8000; telephone number 202-708-2121 (this is not a toll-free
telephone number). Persons with hearing or speech impairments may
access this number through TTY by calling the toll-free Federal
Information Relay Service at 1-800-877-8339.
SUPPLEMENTARY INFORMATION:
I. Background
The National Manufactured Housing Construction and Safety Standards
Act of 1974 (42 U.S.C. 5401-5426) (the Act) authorizes HUD to establish
and amend the Federal Manufactured Home Construction and Safety
Standards (Construction and Safety Standards) codified in 24 CFR part
3280. The Act was amended in 2000 by the Manufactured Housing
Improvement Act of 2000 (Pub. L. 106-569), which expanded the original
Act's purposes and created the MHCC.
The amended Act generally requires that HUD establish Construction
and Safety Standards that are reasonable and practical, meet high
standards of protection, are performance-based, and are objectively
stated. Congress specifically established the MHCC to develop proposed
revisions to the construction and safety standards and included
specific procedures in the Act (42 U.S.C. 5403) for the MHCC process.
MHCC began considering possible revisions to the construction and
safety standards in 2002 and established its own priorities for
selecting revisions for HUD to consider. Included among the first set
of proposals recommended to HUD by MHCC in 2003 were revisions to the
current requirements for roof truss testing.\1\ Those recommendations
were included in HUD's proposed rule to amend the Construction and
Safety Standards, which was published in the Federal Register on
December 1, 2004 (69 FR 70016). After considering comments received on
the proposed rule from both the public and MHCC, HUD agreed with
commenters who wanted HUD to return the proposal on truss testing
procedures to MHCC for further consideration. However, as indicated in
the preamble of HUD's final rule published in the Federal Register on
November 30, 2005 (70 FR 72024), which followed the December 1, 2004,
proposed rule, HUD views truss testing procedures as too important a
safety consideration to leave unresolved.
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\1\ A truss is a triangular structure used to support a roof.
Multiple trusses are used to assemble the framework for a roof.
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HUD requested the MHCC to work expeditiously to reevaluate and
resubmit new proposals for truss testing procedures. As a result, the
Truss Test Task Force of MHCC's Standards Subcommittee was established.
Five teleconferences of this task force were held, and the full MHCC
held two teleconferences to review and vote on new truss testing
procedures. HUD worked closely with MHCC throughout the review and
reevaluation process, and HUD agrees with the majority of the
[[Page 34065]]
new proposals made by MHCC. However, after careful review, HUD has made
editorial revisions to the MHCC proposals and modified the MHCC's
proposal regarding uplift testing. The following is a discussion of the
specific revisions to the current roof truss testing requirements in
Sec. 3280.402 of the Construction and Safety Standards that are
included in this proposed rule.
II. Proposed Changes
The proposed rule would amend various paragraphs of Sec. 3280.402,
Test Procedures for Roof Trusses, of the Construction and Safety
Standards.
A. HUD Questions on Roof Trussing Presented in the November 30, 2005,
Final Rule
In returning the proposal on truss testing procedures to MHCC for
further consideration, HUD asked MHCC, in the preamble to the November
30, 2005, final rule, to consider the following questions during its
deliberations in formulating any revised proposals. The questions asked
and MHCC actions taken are as follows:
(1) Whether the nondestructive testing procedure for roof trusses
that permits a lower overall factor of safety to be used in conducting
the tests based on a presumed low failure rate for roof trusses should
be eliminated.
MHCC Recommendation: In its previous proposal, MHCC recommended
that this procedure be eliminated as a method for initially qualifying
roof trusses. Further, MHCC had determined that the current
requirements for providing minimum quality of materials and workmanship
associated with conducting the nondestructive qualification tests was
impractical and probably not being adhered to in current testing of
roof trusses. However, based on further review of economic factors and
other considerations, MHCC decided to retain the nondestructive test
procedure in its new proposal. MHCC also decided to change the name of
the procedure to the ``proof load truss test procedure'' and added the
requirement that trusses for the initial qualification and testing be
of average quality of materials and workmanship. MHCC also provided for
an increased factor of safety from 1.75 to 2.0 to be used to evaluate
the trusses. MHCC also recommended a reduced load duration period for
the overload test period of 6 hours, rather than the 12-hour period in
the current requirements. This recommendation is based on the
experience of truss fabricators who, in the task force proceedings,
said that failures rarely occur after 6 hours of loading. Under MHCC's
proposal, at least three consecutively tested trusses must pass all
requirements of the test in order to qualify the truss design. More
frequent follow-up testing was also recommended by MHCC due to the
lower factor of safety permitted under this revised proof load truss
testing approach.
(2) Whether upright tensions tests are needed to evaluate the
uplift resistance of the trusses.
MHCC Recommendation: Because of the variation in test results
between trusses tested in the inverted and upright positions for uplift
wind loads identified in earlier tests conducted by the National
Association of Home Builders Research Center (NAHB-RC), MHCC
recommended a factor of safety of 2.5 be used for trusses tested in the
inverted position, but also recommended that the current factor of
safety of 1.75 be retained for trusses tested in the upright position.
Trusses tested in the inverted position consistently failed at higher
average loads (30 to 40 percent), had lower mid-span deflections than
trusses tested in the upright position, and in some truss designs
experienced different failure modes than trusses tested in the upright
position. MHCC also recommended that at least one uplift test be
conducted for certain trusses designed to be used in Wind Zone I and
that three consecutive uplift tests be performed for initial
qualification of all trusses designed to be located in Wind Zones II or
III.
Note that to ensure that manufactured homes survive the threats of
hurricanes and other storms, HUD developed Wind Zone construction
standards. Manufactured homes may be installed only in counties where
they meet the Wind Zone construction standards that apply to that
county. Wind Zone I homes have the least stringent construction
standards and Wind Zone III homes have the most stringent construction
standards. Homes designed and constructed to a higher Wind Zone can be
installed in a lower Wind Zone (a Wind Zone III home can be installed
in a Wind Zone I or II location). However, a Wind Zone I home cannot be
installed in either a Wind Zone II or III area. As Figure 1 below
displays, the overwhelming majority of the United States is designated
as Wind Zone I.
[[Page 34066]]
[GRAPHIC] [TIFF OMITTED] TP16JN10.006
(3) Should the factor of safety for uplift testing be reduced from
2.5 to the current requirement of 1.75, times the design wind
pressures, in consideration of comments received regarding safety
during testing?
MHCC Recommendation: MHCC recommended the use of the higher factor
of safety of 2.5 for only those trusses tested in the inverted
position. The safety concerns expressed in the comments on the December
1, 2004, proposed rule were for the higher loading that would be
required for trusses tested in the upright position and not for trusses
tested in the inverted position and for certain methods of applying the
loads.
(4) What are the costs associated with recommended revisions to the
truss testing requirements?
MHCC Recommendation: The costs associated with its revised proposal
were discussed with representatives of three truss fabricators during
the discussions and deliberations of MHCC in developing its new
recommendations for truss testing procedures. Two factors that would
significantly reduce the cost impacts of the new MHCC proposal, from
the original 2003 one, are recommendations to reinstate the
nondestructive truss test procedure as the proof load truss test
procedure and to generally limit the requirements for uplift tests to
trusses designed for use in Wind Zones II and III (approximately 80
percent of all homes produced are designed for use in Wind Zone I).
B. Comparison Between the Two MHCC Proposals for Truss Testing
The following is a summary of the major differences between the
recommendations in the original MHCC proposal, as published in the
December 1, 2004, proposed rule, and their current recommendations as
incorporated in this proposed rule. (Note: HUD did not modify the MHCC
proposal for truss testing in the December 1, 2004, proposed rule.)
(1) The new proposal would maintain the nondestructive testing
procedure permitted by the current rule, but would rename it as the
``proof load truss test procedure'' and also require three consecutive
passing tests, a safety factor of 2.0 rather than the current 1.75 to
be used in conducting the tests, and more frequent follow-up testing to
be performed. However, the new proposal would reduce the overload test
period from 12 hours to 6 hours, and allow the test specimens to be of
average rather than minimum quality as required by the current rule.
The December 1, 2004, proposed rule would have deleted the current
provision for nondestructive tests in the Construction and Safety
Standards.
(2) In general, the number of required deflection measurements in
this proposed rule would be fewer than originally recommended by MHCC,
which HUD incorporated in the December 1, 2004, proposed rule. Under
the original MHCC recommendation, deflection measurements would have
been required at each truss panel point location and at the mid-span
location between each panel point. This proposed rule incorporates
MHCC's current recommendation that measurements be made at least at the
mid-span and quarter points of the truss. However, scissors or other
unique truss configurations would require measurement at as many
additional bottom truss chord panel points as necessary to obtain an
accurate representation of the deflected shape of the truss, in order
to locate the point(s) of maximum deflection.
(3) The recovery deflections limits after live loads are removed
would be reduced, to L/360, for both the nondestructive and ultimate
test procedures to be consistent with other test standards for truss
testing. The December 1, 2004, proposed rule would have established
recovery limits at a more restrictive level of L/480.
[[Page 34067]]
(4) The new proposed rule would permit trusses to be tested for
uplift loads in either the upright or inverted position. However, the
factor of safety would be reduced to 1.75 for upright tests, while
maintaining the current 2.5 factor of safety for inverted tests. The
new proposal would generally require only three consecutive successful
uplift tests for trusses designed to be used in Wind Zones II and III.
Only one test would be required for trusses designed for use in Wind
Zone I, or, the design may be certified by a Registered Engineer or
Registered Architect or independent third-party agency. The December 1,
2004, proposed rule would have required three uplift tests to be
conducted in all Wind Zones in the upright position using a factor of
safety of 2.5.
(5) The new proposed rule would require at least one follow-up test
to be conducted for each truss design for every 2,500 trusses produced
that are qualified using the revised proof load test procedure. One
follow-up test would be required for every 4,000 trusses produced that
are qualified under the ultimate load test procedure, and the same
frequency of follow-up testing would be required for uplift load tests
(1/2,500 for the proof load test and 1/4,000 for the ultimate load
test) for trusses designed to be used in Wind Zones II and III. The
December 1, 2004, proposal included provisions only for the ultimate
load test procedure; in addition it would have required one test for
every 4,000 trusses produced, and did not include specific requirements
for follow-up testing for uplift load.
As a result of the above differences, the new MHCC recommendations
in this proposed rule would have less of a cost impact than the
recommendations that were included in the December 1, 2004, proposed
rule. Cost analysis prepared by HUD suggests that the change in cost
would primarily be due to a reduction in the estimated number of homes
produced annually, from 170,000 homes to 145,000 homes, and by limiting
the new truss testing provisions for uplift wind forces to Wind Zones
II and III, which affects only about 20 percent of overall truss
production. HUD estimates that this proposed rule would result in an
overall reduction in the estimated cost impact from $13 million
annually, as stated in the December 1, 2004, proposed rule, to about $6
million annually, and would reduce the average cost impact per home
from $77 to $41.
III. Modifications to MHCC Recommendations
After reviewing the proposed recommendations for the revised truss
testing procedures recommended by MHCC, HUD had concerns regarding one
of MHCC's recommendations for uplift load testing. MHCC and HUD had the
opportunity to discuss HUD's concerns during several teleconference
meetings of MHCC, its Standards Subcommittee, and the Truss Test Task
Force. The regulatory text of the MHCC recommendation, as submitted to
HUD, and HUD's changes to that recommendation are published in full in
this proposed rule. HUD is specifically soliciting comments from the
public on both MHCC's recommendation as submitted to HUD, and HUD's
modification of its recommendation.
Other editorial modifications to the document HUD received from
MHCC have been made throughout this proposed rule to be consistent with
the formatting of Federal Register documents or for consistency with
other requirements of the Home Construction and Safety Standards. For
the convenience of the public, rather than publishing both the entire
MHCC document and HUD's edited version of the document, HUD is
publishing a single proposed rule with the original text of the MHCC
document following HUD's discussion.
HUD's Modifications to MHCC's Proposed Revision to Sec. 3280.402(d)(3)
HUD is modifying the proposed recommendation from MHCC on uplift
testing, because the MHCC's provisions for uplift load tests would have
permitted testing in either the inverted or upright position in Wind
Zones II and III. HUD's modification is based in part on the findings
of a study conducted by NAHB-RC, ``Comparison of Methods for Wind
Uplift Load Testing of Roof Trusses for Manufactured Housing,'' and the
requirements of the National Fire Protection Association (NFPA)
consensus process related to uplift testing. In particular, the NAHB-RC
study found that trusses tested in the inverted position failed at
higher loads, had smaller mid-span deflections, and experienced
different fail modes than trusses tested in the upright position. This
is because the difference in truss orientation results in the uplift
load being applied by pulling up on the top chord of the truss in the
upright position (in the manner in which the wind would apply load to
the trusses), while, in the inverted position, the uplift load is
applied by pushing down on the bottom chord of the truss.
HUD modified the MHCC proposal by permitting use of the upright
uplift load test only to evaluate trusses for use in Wind Zones II and
III. HUD made this modification because resistance to high uplift wind
forces is often critical in preventing major damage to the roof or
structure in high-wind areas, and the inverted test may not provide
appropriate assessment of the ability of certain truss designs to
resist those wind loads. However, HUD did accept that part of the MHCC
proposal that allowed either the upright or inverted test method to be
used in Wind Zone I, using the same overload factors recommended by
MHCC. This is because the wind uplift load is relatively small in Wind
Zone I and rarely affects the overall design requirements for the
truss.
The regulatory language submitted by MHCC on this section,
including introductory language that has not been modified but which
provides context for MHCC's language, is as follows:
* * * * *
(d) * * *
(3) Uplift Load Tests. Each truss design must also pass all
requirements of the uplift load test, as applicable, in paragraph
(i) or (ii) and paragraphs (iii) and (iv) of this section.
* * * * *
(iii) Trusses designed for use in Wind Zone I, when tested [see
(i) above], must be tested in either the inverted position to 2.5
times the net wind uplift load or in the upright position to 1.75
times the net wind uplift load. Trusses designed for use in Wind
Zones II and III must be tested in the inverted position to 2.5
times the uplift load, minus the dead load, or to 1.75 times the
uplift load, minus the dead load in the upright position. [See
Figure 3280.402(b)(3)].
(iv) The following describes how to conduct the uplift test with
the truss in the upright position. Similar procedures must be used
if conducting the test in the inverted position.
* * * * *
(D) Continue to load the truss to 1.75 times the net uplift load
and maintain the full load for one minute. (When tested in the
inverted position, continue to load the truss to 2.5 times the net
uplift load and maintain the load for 3 hours.) See paragraph (i)
for the net uplift load in Wind Zone I and paragraph (ii) for the
uplift load for Wind Zones II and III. Regardless of the test
position of the truss, upright or inverted, trusses maintain the
overload for the specified time period without rupture, fracture, or
excessive yielding.
* * * * *
IV. Specific Issues for Comment
The public is invited to comment on any of the specific provisions
included in this proposed rule and is also invited
[[Page 34068]]
to comment on the following questions and on any other related matters
or suggestions regarding this proposed rule:
(1) Under the proposed rule, the proof load test or the ultimate
load test can be used to qualify trusses in high snow load areas.
Should the more stringent and reliable ultimate load test procedure be
required only to qualify roof trusses designed for use in high snow
load areas such as the North and Middle Roof Load Zones, where the risk
of roof and truss failure is greater?
(2) Should the spacing between hydraulic or pneumatic cylinders for
the test fixture be increased from 12 inches to 24 inches in Figures
3280.402(b)(1) and 3280.402(e)(1)? Should the distance between friction
pads along the top chord of the truss of the test fixture be increased
from 6 inches to 12 inches in Figure 3280.402(b)(1)? Should the
distance between one-inch straps attached around the cylinder shoe and
the top chord of the truss of the test fixture be increased from 6
inches to 12 inches in Figure 3280.402(e)(1)?
(3) Should the overload period for all wind uplift tests be
increased from one minute to 3 hours, as is currently required for
uplift tests in the standards for the inverted test procedure?
(4) Should a wind uplift test always be required for trusses
qualified for use in Wind Zone I instead of allowing the determination
to be made by a Registered Engineer or Registered Architect or
independent third-party agency that is certifying the design?
V. Findings and Certifications
Executive Order 12866, Regulatory Planning and Review
The Office of Management and Budget (OMB) reviewed this rule under
Executive Order 12866 Regulatory Planning and Review. This rule was
determined to be a ``significant regulatory action,'' as defined in
section 3(f) of the Order (although not an economically significant
regulatory action under the Order). If adopted in final, this rule
would affect costs for manufactured home manufacturers in two ways.
First, the cost of roof trusses would increase in order to meet the new
testing standards. Second, manufactured home manufacturers would be
required to assure that their truss designs have been retested and
recertified by truss fabricators to comply with the revised testing
requirements. Although this rule would require at least two follow-up
tests per year for each truss design, at the current low production
rates, no additional testing would be needed beyond current practice.
Thus, the retesting provision would not add to the compliance cost of
the rule. The evaluation of costs also depends on the final location
placement of the manufactured homes; that is, in which Wind Zone a
manufactured home is located. HUD has assessed the total costs and
benefits of this rule to be between $7.476 million and $36.447 million
annually.
As noted in the preamble, Wind Zone I homes have the least
stringent construction standards and Wind Zone III homes have the most
stringent construction standards. In addition, Figure 1 in the preamble
evidences, the overwhelming majority of the United States is designated
as Wind Zone I. The estimated cost impact for the proposed rule takes
into consideration the impact on truss construction of the retesting
requirements (which are a one-time cost and not a continuing cost), and
costs for follow-up testing of roof trusses. Each of these is evaluated
with respect to wind zone classifications. Eighty percent of the 55,000
units produced annually are produced to Wind Zone I standards.
The average cost to meet the new standards is $0.50 per truss in
Wind Zone I and $1.00 per truss in Wind Zones II and III. Further,
approximately 30 percent of trusses will require re-design in Wind Zone
I, while all trusses (100 percent) will require redesign for placement
in Wind Zones II and III. Based on an average of 34 trusses per
transportable section in Wind Zone I and 51 in Wind Zone II and III,
and 1.64 transportable sections per home, the total cost of this
requirement is $1.285 million (72,000 transportable sections * 34
trusses per section * $0.50 increase in production cost * 30% of homes
in Wind Zone I; plus 18,000 transportable sections * 51 trusses per
section * $1.00 increase in production cost * 100% of homes in Wind
Zones II & III) annually.
After truss fabricators make any needed changes to truss designs,
manufactured home manufacturers must ensure that all truss designs
being used have been retested and re-certified. The average cost to re-
test and re-certify each truss design is $500. HUD estimates that 1,200
truss designs for Wind Zone I and 300 for Wind Zones II and III will
require re-certification. Thus, the total cost for this requirement
equals $750,000 ($500 cost of re-certification * 1,200 truss designs in
Wind Zone I; plus $500 cost of re-certification * 300 truss designs in
Wind Zones II and III). Totaling the increased construction cost and
the cost of re-certification, this proposed rule, if adopted in final,
would impose a total one-time cost of $2,035,200 on manufacturers of
manufactured housing. Both the re-design and re-certification costs are
one-time costs borne at the time of production. This rule would not
impose any recurring costs.
With respect to benefits, the proposed standards will make
manufactured housing less susceptible to wind damage and downward
pressure by enhancing roof construction. In addition, there will be
less collateral damage to housing and other structures adjacent to
manufactured housing. HUD estimates that the median annual property
damage from hurricanes and tropical storms is $1,879.5 million. Based
on 2008 housing data from the U.S. Postal Service and the Census
Bureau's Survey of Manufactured Housing, newly shipped manufactured
housing accounts for 0.076 percent of the total housing stock in States
prone to hurricane strikes. An approximation of the damage occurring to
manufactured housing totals $1.42 million ($1,879.5 million * 0.076
percent). If this proposed rule were adopted in final, a portion of
this $1.42 million would be avoided annually. Assuming an annual
reduction of the expected property damage by one-fourth ($355,922) to
one-half ($711,904) because of the stronger trusses, the discounted
present value of the annual benefits of the rule would range from
$12.221 to $34.442 million, assuming a 3 percent discount rate, and
from $5.441 to $20.882 million, assuming a 7 percent discount rate. In
addition to avoiding property damage, this rule would also prevent
injuries and deaths that occur during hurricanes, tropical storms, and
other high wind events; although it is difficult to estimate the number
of injuries and deaths that would be prevented. However, it is
reasonable to expect that deaths and injuries would decrease in
response to these proposed standards.
In summary, this proposed rule, if implemented in final, would
impose one-time costs totaling $2.035 million, and create discounted
benefits of $5.441 million to $34.442 million, depending on the
discount rate. Thus, the total impact of this rule--the sum of the
total costs and benefits--would be between $7.476 million and $36.447
million annually.
The docket file is available for public inspection in the
Regulations Division, Office of General Counsel, Department of Housing
and Urban Development, 451 7th Street, SW., Room 10276, Washington, DC
20410-0500. Due to security measures at the HUD Headquarters building,
please schedule an advance appointment to review the public comments by
calling the Regulations Division at 202-402-3055
[[Page 34069]]
(this is not a toll-free number). Individuals with speech or hearing
impairments may access this number through TTY by calling the Federal
Information Relay Service at 800-877-8339.
Environmental Impact
A Finding of No Significant Impact with respect to the environment
has been made in accordance with HUD regulations at 24 CFR part 50,
which implement section 102(2)(C) of the National Environmental Policy
Act of 1969 (42 U.S.C. 4332(2)(C)). That finding is available for
public inspection between the hours of 8 a.m. and 5 p.m. weekdays in
the Regulations Division, Office of General Counsel, Department of
Housing and Urban Development, 451 7th Street, SW., Room 10276,
Washington, DC 20410-0500. Due to security measures at the HUD
Headquarters building, please schedule an appointment to review the
finding by calling the Regulations Division at 202-708-3055 (this is
not a toll-free number).
Regulatory Flexibility Act
The Regulatory Flexibility Act (RFA) (5 U.S.C. 601 et seq.)
generally requires an agency to conduct a regulatory flexibility
analysis of any rule subject to notice and comment rulemaking
requirements, unless the agency certifies that the rule will not have a
significant economic impact on a substantial number of small entities.
This rule would regulate establishments primarily engaged in making
manufactured homes under North American Industry Classification
Standard (NAICS) 32991. The Small Business Administration's size
standards define as small an establishment primarily engaged in making
manufactured homes if it does not exceed 500 employees. Of the 137
manufactured home operations included under this NAICS definition, 60
are small manufacturers that fall below the small business threshold of
500 employees. The rule would apply to all of the manufacturers and
would, therefore, affect a substantial number of small entities. For
the reasons stated below, HUD knows of no instance in which a
manufactured home manufacturer with fewer than 500 employees would be
significantly affected by this rule.
HUD, with the concurrence of the MHCC, conducted an economic cost
impact analysis for this rule. A copy of the analysis is available for
public inspection and copying between 8 a.m. and 5 p.m. weekdays at the
Regulations Division, Office of General Counsel, Department of Housing
and Urban Development, 451 7th Street, SW., Room 10276, Washington, DC
20410-0500. The analysis determined the average potential cost impact,
based on a per-home cost, to be approximately $37, multiplied by an
estimated number of 55,000 homes produced in a year, which equals about
$2.035 million annually. The per-home cost impact would range from
approximately $22 in Wind Zone I, based on an annual production
estimate of 44,000 manufactured homes, to $97 in Wind Zone II and Wind
Zone III, based on a production estimate of 11,000 manufactured homes.
This does not represent a significant economic effect on either an
industry-wide or per-unit basis.
These two relatively small increases in cost would not impose a
significant burden for a small business for homes that typically cost
the purchaser between $40,000 and $100,000. Therefore, although this
rule would affect a substantial number of small entities, it would not
have a significant economic impact on them. Accordingly, the
undersigned certifies that this rule will not have a significant
economic impact on a substantial number of small entities.
Notwithstanding HUD's view that this rule will not have a
significant effect on a substantial number of small entities, HUD
specifically invites comments regarding any less burdensome
alternatives to this rule that will meet HUD's objectives as described
in this preamble.
Executive Order 13132, Federalism
Executive Order 13132 (entitled ``Federalism'') prohibits an agency
from promulgating a regulation that has federalism implications and
either imposes substantial direct compliance costs on State and local
governments and is not required by statute, or the rule preempts State
law, unless the agency meets the consultation and funding requirements
of section 6 of the Executive Order. This rule does not have federalism
implications and does not impose substantial direct compliance costs on
State and local governments or preempt State law within the meaning of
the Executive Order.
Unfunded Mandates Reform Act
Title II of the Unfunded Mandates Reform Act of 1995 (2 U.S.C.
1531-1538) (UMRA) establishes requirements for Federal agencies to
assess the effects of their regulatory actions on State, local, and
Tribal governments and on the private sector. This rule does not impose
any Federal mandates on any State, local, or Tribal governments or the
private sector within the meaning of UMRA.
Catalog of Federal Domestic Assistance
The Catalog of Federal Domestic Assistance number for Manufactured
Home Construction and Safety Standards is 14.171.
List of Subjects in 24 CFR Part 3280
Housing standards, Incorporation by reference, Manufactured homes.
Accordingly, for the reasons stated in the preamble, HUD proposes
to amend 24 CFR part 3280 to read as follows:
PART 3280--MANUFACTURED HOME CONSTRUCTION AND SAFETY STANDARDS
1. The authority citation for part 3280 continues to read as
follows:
Authority: 42 U.S.C. 3535(d), 5403, and 5424.
2. Revise Sec. 3280.402 to read as follows:
Sec. 3280.402 Test procedures for roof trusses
(a) Roof load tests. This section provides the roof truss test
procedure for vertical loading conditions. Where roof trusses act as
support for other members, have eave or cornice projections, or support
concentrated loads, roof trusses must also be tested for those
conditions.
(b) General. Trusses must be tested in a truss test fixture that
replicates the design loads, and actual support points, and does not
restrain horizontal movement. When tested singly or in groups of two or
more trusses, trusses shall be mounted on supports and positioned as
intended to be installed in the manufactured home in order to give the
required clear span distance (L) and eave or cornice distance (Lo), if
applicable, as specified in the design.
(l) When trusses are tested singly, trusses shall be positioned in
a test fixture, with supports properly located and the roof loads
evenly applied. See Figure 3280.402(b)(1).
[[Page 34070]]
[GRAPHIC] [TIFF OMITTED] TP16JN10.007
(2) When tested in groups of two or more, the top chords are
permitted to be sheathed with nominal 1/4-inch x 12-inch plywood
strips. The plywood strips shall be at least long enough to cover the
top chords of the trusses at the designated design truss spacing.
Adjacent plywood strips shall be separated by at least 1/8-inch. The
plywood strips shall be nailed with 4d nails or equivalent staples no
closer than 8 inches on center along the top chord. The bottom chords
of the adjacent trusses shall be permitted to be one of the following:
(i) Unbraced; or
(ii) Laterally braced together (not cross-braced) with 1-inch x 2-
inch stripping no closer than 24 inches on center, nailed with only one
8d nail at each truss. See Figure 3280.402(b)(2).
[GRAPHIC] [TIFF OMITTED] TP16JN10.008
[[Page 34071]]
(c) Measuring and loading methods. Deflections must be measured at
the free end of an eave or cornice projection and at least at the truss
mid-span and quarter points. Scissors or other unique truss
configurations are to be measured at as many additional bottom chord
panel points as necessary to obtain an accurate representation of the
deflected shape of the truss so as to be able to locate and record the
point(s) of maximum deflection. Deflections must be read and recorded
relative to a fixed reference datum. Deflections must be read and
recorded to the nearest 1/32-inch. Dead load must be applied to the top
and bottom chord, and live load must be applied to the top chord
through a suitable hydraulic, pneumatic, or mechanical system or
weights to simulate design loads. Load unit weights for uniformly
distributed top chord loads must be separated so that arch action does
not occur and spaced not more than 12 inches on center so as to
simulate uniform loading. Bottom chord loading must be spaced as
uniformly as practical. Truss gravity loads must be calculated based on
the overall truss length (horizontal projection), including eave or
cornice projections.
(d) Testing procedures. Either the testing method in paragraph
(d)(1) or (d)(2) of this section may be used, and the testing method in
paragraph (d)(3) of this section must be used, to test trusses to
establish compliance with the provisions of these standards.
(1) Proof load truss test procedure. At least three average
quality/consecutively tested trusses must pass all requirements of the
test, for initial qualification of the truss design. All tests for
initial qualification of the truss designs evaluated by this procedure
must be certified by a Registered Engineer or Registered Architect, or
by an independent third-party agency. An in-house quality control and
follow-up testing program (see paragraphs (e) and (f) of this section)
must be approved prior to entering production of any truss design
evaluated by this procedure.
(i) Dead load. Measure and record initial elevation of the truss or
trusses in the test position at no load. Apply dead loads to the top
and bottom chords of the truss that are representative of the actual
weights of materials to be supported by the truss. However, the dead
load may be applied as indicated in paragraph (e)(4) of this section
for ongoing follow-up testing only. Dead loads to be applied to the
truss test assembly are permitted to include only the weights of
materials supported by the truss and not the weight of the truss
itself. However, readings from load cells (when used) on which the test
truss rests must reflect the sum of the applied load plus the weight of
the truss. Apply dead loads and hold for 5 minutes. Measure and record
the deflections.
(ii) Live load. Maintaining the dead loads, apply live load to the
top chord in approximate \1/4\ live load increments until dead load
plus the live load is reached. Measure and record the deflections no
sooner than one minute after each \1/4\ live load increment has been
applied and 5 minutes after the full live load has been reached.
(iii) Initial recovery phase. Remove the design live load but not
the dead load. Measure and record the deflections 5 minutes after the
total live load has been removed.
(iv) Continue to load the truss to dead load plus 2.0 times the
design live load. Maintain this loading for 6 hours and inspect the
truss for failure. Failure is rupture, fracture, or excessive yielding.
(v) Final recovery phase. Remove 2.0 times the design live load,
but not the dead load. Measure and record deflections within 4 hours
after removing 2.0 times the design live load.
(vi) Acceptance criteria. The truss design shall be considered to
have passed if all of the following conditions are met:
(A) The maximum deflection between no load and dead load must be L/
480 or less for simply supported clear spans and Lo/180 or less for
eave and cornice projections; and
(B) The maximum deflection between dead load and design live load
must be L/180 or less for simply supported clear spans and Lo/90 or
less for eave and cornice projections; and
(C) After the design live load is removed and with the dead load
still applied, the maximum recovery deflection must be L/360 or less
for simply supported spans and Lo/180 or less for eave and cornice
projections; and
(D) The truss must maintain the overload condition for 6 hours
without rupture or fracture, or excessive yielding; and
(E) After 2.0 times the design live load has been removed, and with
the dead load still applied, the maximum recovery deflection must be L/
180 or less for simply supported clear spans and Lo/90 or less for eave
and cornice projections; and
(F) As applicable, each truss design must also meet all
requirements for uplift loads required by paragraph (d)(3) of this
section. For Wind Zone I uplift load requirements, see paragraph
(d)(3)(i) of this section. For Wind Zones II and III uplift load
requirements, see paragraph (d)(3)(ii) of this section.
(2) Ultimate load truss test procedure. (i) At least three average
quality/consecutively tested trusses must pass all requirements of the
test, for initial qualification of the truss design. All tests for
initial qualification of the truss designs evaluated by this procedure
must be certified by a Registered Engineer or Registered Architect, or
by an independent third-party agency. An in-house quality control and
follow-up testing program (see paragraphs (e) and (f) of this section)
must be approved prior to entering production of any truss design
evaluated by this procedure.
(ii) Dead load. Measure and record initial elevation of the truss
or trusses in the test position at no load. Apply dead loads to the top
and bottom chords of the truss that are representative of the actual
weights of materials to be supported by the truss. However, the dead
load may be applied as indicated in paragraph (e)(4) of this section
for ongoing follow-up testing only. Dead loads to be applied to the
truss test assembly shall be permitted to include only the weights of
materials supported by the truss, and not the weight of the truss
itself. However, readings from load cells (when used) on which the test
truss rests must reflect the sum of the applied load plus the weight of
the truss. Apply dead loads and hold for 5 minutes. Measure and record
the deflections.
(iii) Live load. Maintaining the dead loads, apply live load at a
uniform rate to the top chord in approximate \1/4\ live load increments
until the dead load plus the live load is reached. Measure and record
the deflections no sooner than one minute after each \1/4\ live load
increment has been applied and 5 minutes after the full live load has
been reached.
(iv) Initial recovery phase. Remove the design live load but not
the dead load. Measure and record the deflections 5 minutes after the
design live load has been removed.
(v) Overload phase. After the recovery phase is completed, reapply
the full live load to the truss assembly. Additional loading shall then
be applied continuously until the dead load plus 2.5 times the design
live load is reached. This overload condition must be maintained for at
least 5 minutes.
(vi) Final recovery phase. Remove 2.5 times the design live load
but not the dead load. Measure and record deflections within 4 hours
after 2.5 times the design live load has been removed.
(vii) Acceptance criteria. The truss design is considered to be
acceptable if all of the following conditions are met:
[[Page 34072]]
(A) The maximum deflection between no load and dead load must be L/
480 or less for simply supported clear spans and Lo/180 or less for
eave and cornice projections; and
(B) Dead load-to-design live load deflections shall be L/180 or
less for simply supported clear spans and Lo/90 or less for eave and
cornice projections; and
(C) After the design live load is removed and with the dead load
still applied, the maximum recovery deflection must be L/360 or less
for simply supported spans and Lo/180 or less for eave and cornice
projections; and
(D) The truss shall maintain the overload condition for 5 minutes
without rupture, fracture, or excessive yielding; and
(E) After 2.5 times the design live load is removed and with the
dead load still applied, the truss must recover to at least L/180 for
simply supported clear spans, and Lo/90 for eave and cornice within 4
hours after the total live load has been removed; and
(F) As applicable, each truss design must also meet all
requirements for uplift loads in Wind Zone I or Wind Zone II and III,
as required by paragraph (d)(3) of this section. For Wind Zone I uplift
load requirements, see paragraph (d)(3)(i) of this section. For Wind
Zones II and III uplift load requirements, see paragraph (d)(3)(ii) of
this section.
(3) Uplift load tests. Each truss design must also pass all
requirements of the uplift load test, as applicable, in paragraph
(d)(3)(i) or (d)(3)(ii) and paragraphs (d)(3)(iii) and (d)(3)(iv) of
this section.
(i) Wind Zone I uplift load test. Where there are engineered
connectors between the top chord and web members of the truss, such as
metal connector plates or wood gussets or their equivalents, uplift
testing in Wind Zone I is at the discretion of the Registered Engineer
or Registered Architect or independent third-party agency certifying
the truss design. When testing is deemed necessary by the Registered
Engineer or Registered Architect or independent third-party agency
certifying the truss design, a minimum of one average quality uplift
load test is to be conducted for each such truss design and must pass
all requirements of the test for initial qualification of the truss
design. The net uplift load for trusses designed for use in Wind Zone I
is 9 psf for the clear span of the truss and 22.5 psf for eave or
cornice projections.
(ii) Wind Zones II and III uplift loads test. This test is required
for all trusses designed for use in Wind Zones II and III. A minimum of
three average quality/consecutive uplift load tests are to be conducted
for each truss design, and the trusses must pass all requirements of
the test for initial qualification of the truss design. The uplift load
for trusses designed to be used in Wind Zones II and III for the clear
span or eave cornice projections is to be determined by subtracting the
dead load applied to the truss from the uplift load provided in the
Table of Design Wind Pressures in Sec. 3280.305(c)(1)(ii)(B).
(iii) Trusses designed for use in Wind Zone I, when tested (see
paragraph (d)(3)(i) of this section), must be tested in either the
inverted position to 2.5 times the net wind uplift load or in the
upright position to 1.75 times the net wind uplift load. Trusses
designed for use in Wind Zones II and III (see paragraph (d)(3)(ii) of
this section) must be tested to 1.75 times the uplift load minus the
dead load in the upright position. (See Figure 3280.402(b)(3).)
(iv) The following describes how to conduct the uplift test with
the truss in the upright position. Similar procedures must be used if
conducting the test in the inverted position.
(A) Place the truss in the test fixture and position as it is
intended to be installed in the manufactured home. See Figure
3280.402(b)(3).
[[Page 34073]]
[GRAPHIC] [TIFF OMITTED] TP16JN10.009
(B) Position the load measurement devices to register the wind
uplift loads that will be applied to the top chord of the truss. The
uplift loads shall be applied through tension devices not wider than
one inch and spaced not greater than approximately 12 inches on center
and shall be applied as uniform as possible, so as to simulate uniform
loading. Gravity and wind uplift load tests may be performed on the
same truss in this single set-up mode. For the wind uplift test, it is
permissible to stabilize the bottom chord of the truss in the test
fixture to simulate ceiling materials or purlin supports. Measure and
record the initial elevation of the bottom chord of the truss in the
test position at the mid-span and quarter points of the truss, and at
the free end of an eave or cornice projection greater than 12 inches.
Scissors or other unique truss configurations are to be measured at as
many additional bottom chord panel points as necessary to obtain an
accurate representation of the deflected shape of the truss, so as to
be able to locate and record the point(s) of maximum deflection. Eave
or cornice projection loads are applied separately for eaves or cornice
projections greater than 12 inches. For eave or cornice projections
greater than 12 inches, the additional required load must be applied to
the eave simultaneously with the main body load. For eave or cornice
projection 12 inches or less, add the additional required load to the
main body load and apply it to the entire top chord.
(C) Measure and record the deflection 5 minutes after the net
uplift load has been applied. Design load deflection shall be L/180 or
less for a simply supported clear span and Lo/90 or less for eave or
cornice projections.
(D) For trusses tested in the upright position, continue to load
the truss to 1.75 times the net uplift load in paragraph (d)(3)(i) of
this section for Wind Zone I and 1.75 times the uplift load in
paragraph (d)(3)(ii) for Wind Zones II and III, and maintain the load
for one minute. For trusses tested in the inverted position (Wind Zone
I only), continue to load the truss to 2.50 times the net uplift load
in paragraph (i) for Wind Zone I, and maintain the full load for 3
hours. Regardless of the test position of the truss, upright or
inverted, trusses must maintain the overload for the specified time
period without rupture, fracture, or excessive yielding.
(E) Follow-up Testing. Follow-up testing procedures must include
the following:
(1) All trusses qualifying under these test procedures must be
subject to a quality control and follow-up testing program.
Manufacturers of listed or labeled trusses must follow an in-house
quality control program, with follow-up testing approved by an
independent third party as specified in Sec. 3280.402(f). Those home
manufacturers producing trusses for their own use, and which are not
listed or labeled, must have an in-house quality control program that
includes follow-up testing, as specified in this section, and approved
by their Design Approval Primary Inspection Agency (DAPIA).
(2) Truss designs that are qualified but not in production are not
subject to follow-up testing until produced. When the truss design is
brought into production, a follow-up test is to be performed if the
truss design has been out of production for more than 6 months.
(3) The frequency of truss manufacturer's quality control follow-up
testing for trusses must be at least:
(i) One test for every 2,500 trusses for trusses qualified under
the proof load truss test procedure or once every 6
[[Page 34074]]
months, whichever is more frequent, for every truss design produced; or
(ii) One test for every 4,000 trusses produced for trusses
qualified under the ultimate load truss test procedure or once every 6
months, whichever is more frequent, for every truss design produced.
(iii) Uplift load tests are also to be conducted at the same
follow-up testing frequency in paragraph (e)(3)(i) or paragraph
(e)(3)(ii) of this section for trusses designed for use in Wind Zones
II and III.
(4) For follow-up testing only, the full dead load may be applied
to the top chord of the truss, when the bottom chord dead load is 5 psf
or less.
(F) In-house quality control program. The in-house quality control
program must include, at a minimum, procedures for quality of materials
including, but not limited to, grade(s) of materials, allowable splits,
knots, and other applicable lumber qualities; workmanship including,
but not limited to, plate placement and embedment tolerances; other
manufacturing tolerances; description and calibration of test
equipment; truss re-testing criteria; and procedures in the event of
noncomplying results.
Dated: May 4, 2010.
David H. Stevens,
Assistant Secretary for Housing--Federal Housing Commissioner.
[FR Doc. 2010-14277 Filed 6-15-10; 8:45 am]
BILLING CODE 4210-67-P