Model Manufactured Home Installation Standards, 21498-21559 [05-7497]

Agencies

• DEPARTMENT OF HOUSING AND URBAN DEVELOPMENT

[Federal Register Volume 70, Number 79 (Tuesday, April 26, 2005)]
[Proposed Rules]
[Pages 21498-21559]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 05-7497]



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Part II





Department of Housing and Urban Development





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24 CFR Parts 3280 and 3285



Model Manufactured Home Installation Standards; Proposed Rule

Federal Register / Vol. 70, No. 79 / Tuesday, April 26, 2005 / 
Proposed Rules

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DEPARTMENT OF HOUSING AND URBAN DEVELOPMENT

24 CFR Parts 3280 and 3285

[Docket No. FR-4928-P-01; HUD-2005-0006]
RIN 2502-AI25


Model Manufactured Home Installation Standards

AGENCY: Office of the Assistant Secretary for Housing--Federal Housing 
Commissioner, HUD.

ACTION: Proposed rule.

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SUMMARY: This proposed rule would establish new Model Manufactured Home 
Installation Standards (Model Installation Standards) for the 
installation of new manufactured homes and would include standards for 
the completion of certain aspects necessary to join all sections of 
multi-section homes. The National Manufactured Housing Construction and 
Safety Standards Act of 1974 requires the Secretary to develop and 
establish Model Installation Standards after receiving proposed 
installation standards from the Manufactured Housing Consensus 
Committee (MHCC). HUD received and reviewed the MHCC's recommended 
model installation standards and is in agreement with a significant 
majority of the recommendations. Following discussion with the MHCC at 
its August 2004 meeting, HUD provided the MHCC with a draft of this 
proposed rule establishing the Model Installation Standards. During 
three ensuing conference calls with the MHCC and its subcommittee on 
installation, HUD received additional feedback and comment from the 
MHCC and its members that were considered for inclusion in this 
proposed rule.
    Within this proposed rule, HUD is providing its proposed Model 
Installation Standards, and a detailed summary of its recommended 
changes to the MHCC's proposal. The proposed rule also incorporates 
certain amendments to definitions contained in the Manufactured Home 
Construction and Safety Standards (MHCSS) that are affected by 
definitions provided in the Model Installation Standards. HUD is 
specifically requesting comment on proposed installation standards 
applicable to completing work and conducting adequate inspections 
necessary to join all sections of a multi-section manufactured home, as 
well as many other areas of manufactured home installation that may 
need consideration before final publication.

DATES: Comments Due Date: June 27, 2005.

ADDRESSES: Interested persons are invited to submit comments regarding 
this rule to the Regulations Division, Office of General Counsel, Room 
10276, Department of Housing and Urban Development, 451 Seventh Street, 
SW., Washington, DC 20410-0500. Interested persons may also submit 
comments electronically through either:
     The Federal eRulemaking Portal at: https://
www.regulations.gov; or
     The HUD electronic Web site at: https://www.epa.gov/
feddocket. Follow the link entitled ``View Open HUD Dockets.''
    Commenters should follow the instructions provided on that site to 
submit comments electronically. Facsimile (FAX) comments are not 
acceptable. In all cases, communications must refer to the docket 
number and title. All comments and communications submitted will be 
available, without revision, for public inspection and copying between 
8 a.m. and 5 p.m. weekdays at the above address. Copies are also 
available for inspection and downloading at https://www.epa.gov/
feddocket.

FOR FURTHER INFORMATION CONTACT: William W. Matchneer III, 
Administrator, Office of Manufactured Housing Programs, Room 9164, 
Department of Housing and Urban Development, 451 Seventh Street, SW., 
Washington, DC 20410; telephone (202) 708-6401 (this is not a toll free 
number). Persons with hearing or speech impairments may access this 
number via TTY by calling the toll free Federal Information Relay 
Service at 1-800-877-8389.

SUPPLEMENTARY INFORMATION: 

I. Background

    On December 27, 2000, the National Manufactured Housing 
Construction and Safety Standards Act of 1974 (42 U.S.C. 5401-5426) 
(the Act) was amended by the Manufactured Housing Improvement Act of 
2000, which, among other things, provided for the creation of the 
Manufactured Housing Consensus Committee (MHCC) and established new 
requirements pertaining to the installation of new manufactured homes. 
One of the provisions of the Act requires the Secretary to establish 
Model Installation Standards for new manufactured homes. The Act also 
gave the MHCC responsibility to develop and submit proposed model 
manufactured home installation standards. The MHCC recommendations were 
to be submitted to HUD not later than 18 months after the initial 
appointment of all committee members. The MHCC held its first meeting 
in August 2002 and began work on its installation standards 
recommendations by reviewing the already developed consensus standard 
National Fire Protection Agency (NFPA) 225, with draft updates 
maintained by the National Fire Protection Association (NFPA) through 
September 2002. Subsequently, the MHCC approved proposed installation 
standards and submitted them to HUD on December 18, 2003. HUD reviewed 
the recommendations and developed a draft proposed rule that was based 
upon those recommendations. Following its review of the draft proposed 
rule, the MHCC provided additional recommendations to HUD on September 
3, 2004.
    The complete MHCC recommendations relating to model manufactured 
home installation standards, including the transmittal letter to HUD 
and the MHCC's description of its installation standards development 
assumptions and principles, can be found on the Web site maintained by 
the NFPA, the administering organization for the MHCC, at https://
www.nfpa.org/PDF/MHCC FinalChangesInstallStd.pdf?src=nfpa.
    At the MHCC's meeting on August 10, 2004, HUD presented orally and 
in writing an overview of its initial response to the MHCC's 
recommendations. The most significant change to the MHCC proposal 
related to the removal of several MHCC-suggested installation standards 
for on-site completion of multi-section homes, which HUD deemed to be 
related to construction and assembly of the home rather than 
installation. Upon evaluating further comments received from the MHCC, 
and based upon its own review, HUD incorporated a majority of the 
applicable ``close up'' standards proposed by the MHCC in this proposed 
rule. HUD provided the MHCC with a draft of this proposed rule for 
review and comment on August 19, 2004. During three ensuing conference 
calls with the MHCC and its subcommittee on installation, HUD received 
additional feedback and comment from the MHCC and its members that HUD 
considered in preparing this proposed rule. In addition, HUD has added 
several questions to the preamble seeking comment on issues where 
consensus within the MHCC was not reached or regarding other issues on 
which HUD would like targeted feedback.
    As indicated, HUD has carefully reviewed the MHCC's recommended

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model installation standards and is in agreement with a significant 
majority of them. For the reasons set forth below in the Summary of 
Changes to the MHCC Proposed Installation Standards, modifications were 
made to some of the recommendations. The summaries of HUD's proposed 
Model Installation Standards and changes to the MHCC's recommendations 
include questions on which HUD seeks comment. The following is a 
section-by-section discussion of the new Model Installation Standards 
proposed by HUD.

I. Summary of HUD's Model Manufactured Home Installation Standards

    HUD proposes to codify the Model Installation Standards in a new 
part 3285 of title 24 of the Code of Federal Regulations (CFR). HUD has 
chosen not to codify these installation standards as part of the 
Construction and Safety Standards (24 CFR part 3280), to avoid 
confusion between construction and installation and to assist in 
assigning clear lines of responsibility among the parties involved for 
construction versus installation issues. Moreover, the Act makes a 
clear distinction between the Federal Manufactured Home Construction 
and Safety Standards (MHCSS) and the Model Installation Standards. 
Section 604 of the Act (42 U.S.C. 5403) sets forth specific provisions, 
including preemption, which are applicable only to the MHCSS. The Act 
sets forth provisions applicable only to manufactured home installation 
and the Model Installation Standards in section 605 (42 U.S.C. 5404).
    The proposed rule provides that, at a minimum, manufactured home 
manufacturers must include installation instructions with each new 
home. The instructions must be approved by a design approval primary 
inspection agency (DAPIA) and must provide protection to the residents 
of manufactured homes that equals or exceeds the protections provided 
by the Model Installation Standards. In addition, States that desire to 
operate an installation program must adopt installation standards that 
provide protection that equals or exceeds the protections provided by 
the Model Installation Standards.
    HUD is soliciting comments on the distinction between standards for 
the construction and assembly of manufactured homes and the standards 
for the installation of manufactured homes established by this proposed 
rule. Generally, HUD has in the past considered those activities that 
are completed at the installation site to bring the home into 
conformance with the MHCSS as being part of construction and covered by 
the manufacturer's certification label. HUD has also considered as 
being part of construction those activities that for a multi-wide home 
are completed at the installation site, but for a singlewide home are 
performed in the factory prior to labeling the home, as well as 
activities required to finish the home at the installation site that 
are presently covered by the Alternative Construction process. On the 
other hand, HUD has considered installation to include the siting, 
supporting, stabilizing, and anchoring of the home.
    Based on HUD's further review and consideration of the 
recommendations of the MHCC, HUD has included specified activities 
necessary for the close up and joining of all sections of a multi-
section manufactured home as part of the Model Installation Standards. 
Installers, not manufacturers, typically perform close up work. Under 
the proposed rule, home purchasers generally would have to look to 
installers or retailers, who often employ or contract with installers 
to perform home installations, to remedy close up problems that are not 
the result of inadequate or incorrect manufacturer instructions or are 
manufactured in such a way that the sections do not fit together 
properly. This is because close up activities would not be covered by 
the manufacturer's notification and correction responsibilities for 
construction defects standards under section 615 of the Act (42 U.S.C. 
5414). However, including close up provisions in the Model Installation 
Standards would also mean that, in accordance with the Act, a State 
that operates an installation program in lieu of the HUD program will 
have to provide for inspections that include close up work.
    Under the current enforcement of the MHCSS, as well as State and 
local enforcement of installations, inspection for close up activities 
is generally not conducted by primary inspection agencies, States, 
local authorities, or HUD. HUD and the MHCC are of the opinion that 
improper close up is an area of significant concern for manufactured 
housing, and believe that the Model Installation Standards provide an 
opportunity to better address both close up and installation. 
Therefore, the proposed rule would include close up activities in the 
Model Installation Standards. Thus, close up work completed on site 
would be inspected under regulations to establish an installation 
program that will be published by HUD for public comment in a separate 
rulemaking. While HUD recognizes that there may be reasons to include 
close up activities as part of the MHCSS, the MHCC and HUD believe 
there is a practical necessity to include these aspects as installation 
standards, which would be inspected by States or HUD under installation 
program requirements. HUD believes that the Model Installation 
Standards as proposed, the additional requirement for inspection of 
installation and close up work through HUD's future installation 
program rule, and HUD's forthcoming dispute resolution regulation 
(which will also be published separately for public comment in a future 
rulemaking and would involve consumers, manufacturers, retailers, and 
installers) will provide greater protections to the residents of 
manufactured homes.
    HUD would like to receive comments, in particular from installers, 
retailers, and manufactured home owners, on the legal and practical 
effect of these proposals. Since close-up consists of the work and 
activities for completing the assembly of the home, is it consistent 
with the rest of the Act to consider such work as construction and 
therefore the responsibility of the manufacturer? Or is it too 
difficult for manufacturers to control and monitor the close-up done by 
installers so that it would be more appropriate to classify close up as 
part of installation? Will consumers be adequately protected if close-
up is classified as part of installation?
    HUD would also very much appreciate receiving comments from the 
States and local governments on this subject. How do the States and 
municipalities presently treat close up activities? Do their inspectors 
review close up activities as part of installation inspections? If 
there were requirements for inspection of close up work as part of 
HUD's certification of a State installation program, would there be 
difficulties with the expertise or work load of the State or local 
inspectors with respect to close ups, such that State installation laws 
could not be certified as covering inspection of close up work? 
Finally, HUD is very interested in hearing from States concerning 
whether the Model Installation Standards proposed in this rule would 
work well with the present installation programs in the States.

Summary--Part 3285 Model Manufactured Home Installation Standards

Subpart A--General
    Subpart A of the new part 3285 would include general provisions 
relevant to

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the overall use and applicability of the Model Installation Standards. 
These general provisions include statements of the scope (Sec.  
3285.1(a)) and applicability (Sec.  3285.1(b)). The Model Installation 
Standards are applicable to the installation of new manufactured homes 
and would include those specific aspects of a typical installation that 
would be necessary to join all sections of a multi-section home. As a 
result, these close-up and crossover aspects would not be considered 
assembly under the Act's definition of ``manufactured home 
construction.'' This means that installers, rather than manufacturers, 
would be responsible for the great majority of problems relating to 
those aspects of erecting a home.
    States that choose to operate an installation program, as will be 
addressed by HUD under separate provisions set forth in a subsequent 
proposed rule, must implement installation standards that provide 
protection that equals or exceeds the protection to the residents of 
manufactured homes provided by these Model Installation Standards. 
Qualifying States may choose to establish or permit more stringent 
installation standards. However, States that do not establish standards 
that provide a level of protection that meets or exceeds the level of 
protection of these model provisions will not have qualifying programs.
    In States that do not choose to operate an installation program, 
HUD intends to regulate and enforce the installation of new 
manufactured homes through a program to be established separately in a 
subsequent rulemaking, using these Model Installation Standards for 
minimum design and installation requirements. In these States, the 
State or municipalities also may establish more stringent requirements, 
so long as the requirements provide protection that equals or exceeds 
the protection provided by the Model Installation Standards.
    Under the proposed rule, manufacturers would be required to provide 
installation instructions (Sec.  3285.2) with each new home that would 
be approved by the DAPIAs as providing the residents protection that 
equals or exceeds the protection provided by the Model Installation 
Standards. The manufacturer's installation instructions must not take 
the home out of compliance with the MHCSS (24 CFR part 3280), and must 
provide adequate instructions to complete those limited aspects of the 
installation that are necessary to join all sections of a multi-section 
home. HUD intends home manufacturers to be responsible for adequate and 
conforming installation instructions. However, through enforcement and 
dispute resolution regulations yet to be published for comment, 
installers or retailers would be accountable and responsible for work 
completed at the installation site in accordance with the 
manufacturers' instructions.
    HUD is also providing, in subpart A, general requirements for 
alterations completed during the initial installation that affect the 
installation of the home (Sec.  3285.3). This section ensures that any 
alterations will not adversely affect compliance with the Model 
Installation Standards, and that any such alteration does not take the 
home out of compliance with the MHCSS. The provision prohibits 
alterations, as defined by 24 CFR 3282.7, from imposing additional 
loads to the manufactured home or its foundation without following a 
design by a registered engineer or registered architect, or express 
inclusion in the manufacturer's approved installation instructions.
    Consistent with other construction-type standards, HUD would 
incorporate several specifications, standards and codes by reference 
(Sec.  3285.4) pursuant to 5 U.S.C. 552(a) and 1 CFR part 51. Reference 
standards have the same force and effect as the other Model 
Installation Standards except that whenever reference standards and the 
Model Installation Standards are inconsistent, the requirements of the 
Model Installation Standards would prevail to the extent of the 
inconsistency. Section 3285.5 provides definitions for terms contained 
in the Model Installation Standards.
Subpart B--Pre-Installation Considerations
    The majority of Subpart B would contain provisions for the 
installation of new manufactured homes in flood hazard areas. 
Consistent with current practice, the Model Installation Standards 
would make the installer responsible to evaluate the prospective 
installation site to determine if the location is in a flood hazard 
area (Sec.  3285.101). If so located, the installer must refer to the 
Federal Emergency Management Agency's National Flood Insurance Program 
for specific requirements and further guidance relating to installation 
in flood hazard areas.
    Seismic safety has not been addressed in this proposed rule 
primarily because seismic safety is not a required consideration in the 
construction of manufactured homes under the preemptive Manufactured 
Home Construction and Safety Standards (24 CFR part 3280). However, in 
areas where seismic activity is a concern, some State and local 
jurisdictions currently implement and enforce installation provisions 
that address seismic safety. Because the Model Installation Standards 
are minimum standards, these jurisdictions will continue to have full 
authority to implement and enforce seismic safety considerations. 
Should the Model Installation Standards attempt to set forth minimum 
installation requirements or pre-installation considerations to address 
seismic safety? If so, how should HUD establish seismic zones and what 
minimum requirements would be included in the Model Installation 
Standards?
    The Model Installation Standards would incorporate by reference the 
design zone maps (Sec.  3285.102) provided in the MHCSS (24 CFR part 
3280) to ensure that the design and construction of the home's 
foundation and anchorage is compatible with the design and construction 
of the manufactured home.
    In addition, the proposed Model Installation Standards recognize 
the need to evaluate other practical considerations for the 
installation site (Sec.  3285.103) and obtain all permits necessary for 
installation work, alterations, or other site-built structures (Sec.  
3285.104). While HUD would not regulate these considerations, reference 
to subpart J of this proposed rule is provided to establish 
considerations for which a home manufacturer must provide caution to 
the installer.
Subpart C--Site Preparation
    Subpart C is to establish requirements for the preparation of the 
site where a manufactured home would be installed and requires 
assessment of the soil at the installation site to ensure proper design 
and construction of the home's foundation and anchorage.
    The Model Installation Standards would also provide for site 
evaluation of the soil (Sec.  3285.201) and determination of soil 
classification and bearing capacity (Sec.  3285.202) to ensure that a 
particular foundation and anchorage design would be adequate for the 
home design and location. The Model Installation Standards provide for 
three general methods of determining the bearing capacity and 
classification of the soil at the installation site. Soils may be 
tested to determine the appropriate soil classification, bearing 
capacity, and torque probe values, or the records on file with a local 
authority having jurisdiction (LAHJ) may be used to determine these 
soil characteristics. Alternately, if the soil can be identified

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by type, a table is provided for use in determining appropriate bearing 
capacity and soil classification including corresponding torque probe 
values. The Model Installation Standards would require consultation 
with a registered professional if unusual or suspect soil conditions 
were present.
    The proposed Model Installation Standards also include provisions 
to ensure that surface water is adequately drained to prevent water 
build-up under the home (Sec.  3285.203). The Model Installation 
Standards would require a minimum one-half inch per foot slope away 
from the home for the first ten feet, and require the home to be 
protected from surface runoff. If the slope cannot be obtained for ten 
feet due to property lines or other physical conditions, the site would 
need to be provided with drainage that will carry surface runoff away 
from the foundation. The standard would also require other runoff from 
gutters and downspouts to be directed away from the home.
    If the space under the home is enclosed with skirting or otherwise 
similarly enclosed, the Model Installation Standards would require a 
vapor retarder to keep ground moisture from entering the home (Sec.  
3285.204). Arid regions with dry soil conditions, as well as areas 
under open decks, porches, or recessed entries would be exempt from 
vapor barrier requirements. The Model Installation Standards would also 
provide for minimum vapor barrier material requirements and proper 
installation techniques. The requirements for vapor barrier 
installation permit minor voids and tears without repair. However, HUD 
is concerned that the excessive voids and numerous tears can defeat the 
purpose of the requirement. Therefore, should limitations be placed on 
the number and size of voids and tears? If so, what specific 
limitations would be recommended?
Subpart D--Foundations
    The Model Installation Standards would require foundations for 
manufactured home installations to be based on site conditions, home 
design features, and the loads the home was designed to withstand as 
evidenced on the home's data plate (Sec.  3285.301). The Model 
Installation Standards would provide prescriptive methods for 
constructing a foundation composed of piers and footings traditionally 
addressed by the manufacturer's installation instructions. While the 
Model Installation Standards include tables to size piers and footings, 
home manufacturers may elect to provide installation instructions that 
are compatible with the homes and options designed and constructed in 
their factories. However, the manufacturer's instructions must provide 
protection to residents that equals or exceeds the protection provided 
through the tables as based on assumptions outlined in table footnotes, 
and the design loads for which the home was constructed. When a home's 
design configuration differs from the design limitations noted in table 
footnotes, manufacturers or design professionals must use the design 
loads for which the home was constructed (based on the MHCSS) to design 
adequate support and anchorage. Equivalent pier and footing 
instructions, consistent with the presentation of data in the Model 
Installation Standards, would require substantiation through 
engineering design and analysis (Sec.  3285.301(b) and (c)).
    HUD Questions: Is it clear in the proposed rule that the described 
tables and charts for piers, footings, and anchor spacing are meant to 
provide example requirements for homes that have characteristics 
consistent with the respective design assumption footnotes? Is it clear 
that variations to tables and charts may be achieved through other 
installation methods or specifications and that the inclusion of 
variations within the manufacturer's installation instructions is both 
acceptable and may be required in order to assure continued compliance 
of the home with the MHCSS? Do the Model Installation Standards provide 
an adequate basis for preparing manufacturer's instructions that meet 
the level of protection provided by the Model Installation Standards 
when other installation methods are used? Do the Model Installation 
Standards need to include clearer performance equivalents so that 
alternative installation methods may be developed and subsequently 
approved or certified by Design Approval Primary Inspection Agencies 
(DAPIAs) or registered engineers or architects, as applicable? Can 
manufacturers comply consistently with both the MHCSS and the Model 
Installation Standards as proposed? Since the Model Installation 
Standards are intended to provide requirements for manufacturers to 
develop installation instructions, should the prescriptive provisions 
found in the tables for pier and footing sizing and anchor spacing be 
more appropriately placed in an appendix? Should the different 
specifications included in approved manufacturer installation 
instructions be required to be formatted to present pier, footer, and 
anchor spacing consistent with the presentation of data in the tables 
and charts of the Model Installation Standards?
    The Model Installation Standards would also permit alternative 
foundation design (Sec.  3285.301(d)). The alternative foundation 
design and support requirements would be determined by a registered 
professional engineer, registered architect, or nationally recognized 
third party testing agency in accordance with a nationally recognized 
testing protocol and must safely support the home as required by Sec.  
3285.301. However, HUD is not aware of an existing nationally 
recognized testing protocol or standard established to determine the 
support capability of proprietary-type foundation systems. While the 
proposed Model Installation Standards do refer to a national test 
protocol, HUD is requesting comments on specific requirements that 
should be considered and contained in such a protocol.
    As determined from flood hazard evaluation required in Subpart B, 
if the home is located wholly or partly in a flood hazard area, the 
support system would need to be capable of resisting gravity loads as 
well as design flood and wind loads (Sec.  3285.302).
    Generally, the Model Installation Standards would require piers to 
be capable of transmitting the vertical live and dead loads to the 
footings or foundation below (Sec.  3285.303). Piers may be made of 
concrete blocks, pressure-treated wood, or adjustable metal or concrete 
piers. Piers, if manufactured, would be required to be listed (Sec.  
3285.5) according to the intended use.
    The load that each pier must carry depends on many variables. Such 
variables include the dimensions of the home, the design dead and live 
loads, the spacing of the piers, and the way the piers are used to 
support the home. Manufacturers' installation instructions would be 
required to have pier and footing requirements that provide protection 
to manufactured home residents that equals or exceeds the protection 
provided by the design support configurations indicated in several 
tables provided in (Sec.  3285.303(d)), based on certain design 
assumptions noted in footnotes.
    The tables were prepared based upon worst-case design assumptions 
for current typical construction. However, the intended applicability 
of the tables is outlined and limited by the footnotes to the tables. 
It is HUD's intent that manufacturers or other parties may engineer and 
develop other pier and footing sizes and spacings for homes with 
characteristics that are outside of the design assumptions of the 
tables,

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provided that the engineered design provides protection to residents 
that equals or exceeds the protection provided by the specific design 
assumptions and specifications of the tables.
    Table 3285.303(d)(1)(i) provides the model pier load and footing 
requirements for manufactured homes that are designed to be supported 
only at the frame and without additional perimeter support, except for 
perimeter support required at openings. Table 3285.303(d)(1)(ii) 
provides the model pier load and footing requirements for manufactured 
homes that are designed for support both at the frame and at the 
perimeter with support at specified spacings. Table 3285.303(d)(1)(iii) 
provides the minimum pier load and footing requirements for ridge beam 
column supports applicable to the mate-line of multi-section homes. For 
opening spans between those specifically included in the table, pier 
loads interpolated for the specific span may be used to design piers 
and footings.
    The Model Installation Standards (Sec.  3285.304) would also 
provide for specific materials, dimensions, and illustrations that 
establish the model design and construction requirements for concrete 
block piers and pier caps. Pier caps would be designed for structural 
loads to evenly distribute the loads across hollow block piers.
    HUD recognizes that gaps occur between the bottom of the supported 
beam and the foundation support system during typical installations. 
The Model Installation Standards would provide material and thickness 
requirements acceptable to fill these gaps. The Model Installation 
Standards would also provide requirements (Sec.  3285.305) for 
maintaining minimum clearances under homes.
    The Model Installation Standards would provide minimum design 
procedures for typical concrete block piers, single or double stacked, 
including limitations and requirements for pier heights and block 
orientation in Sec.  3285.306. The Model Installation Standards would 
require design by the manufacturer or a registered professional 
engineer or architect for unusual or special pier conditions, such as 
high or elevated piers (Sec. Sec.  3285.306(c) and 3285.309).
    The Model Installation Standards would also address requirements 
for locating piers along the mate-line of multi-section homes. Figures 
3285.310(a), 3285.310(b), and 3285.310(c) illustrate typical pier 
locations including pier and footing table references, applicable to 
mate-line locations and the appropriate support configuration.
    The Model Installation Standards (Sec.  3285.311) would require 
pier supports on both sides of side wall exterior doors and any other 
side wall openings greater than 48 inches (such as entry and sliding 
glass doors), and under porch posts, factory installed fireplaces, and 
wood stoves. Additional or alternate perimeter supports would be 
required in accordance with the design of the home, but would require 
use of the appropriate pier load and footing configuration tables as 
determined by the home manufacturer or a registered professional 
engineer or architect.
    The Model Installation Standards (Sec.  3285.312) would require 
footings to support every pier. Footings would have to be placed on 
undisturbed soil or fill compacted to 90 percent of maximum relative 
density. Figures 3285.312(a) and 3285.312(b) illustrate typical footing 
and pier (blocking) diagrams for single and multi-section homes.
    Acceptable footing materials (Sec.  3285.312(a)) and specific 
listing or labeling requirements would be required and identified, as 
appropriate for each material. Footings placed in freezing climates 
(Sec.  3285.312(b)) would be required to be placed below the frost line 
depth unless a registered professional engineer or architect properly 
designs an insulated foundation or slab-type foundation (Sec.  
3285.312(b)) in accordance with a nationally recognized design standard 
for frost-protected shallow foundations. The Model Installation 
Standards do not contain provisions for reinforced cast-in-place 
footings.
    HUD Questions: When desired or required, should the Model 
Installation Standards provide minimum steel reinforcement 
specifications for cast-in-place footings? What information should the 
Model Installation Standards include to adequately provide for the 
design of such footings? Should the Model Installation Standards 
incorporate nationally recognized consensus standards such as the 
American Concrete Institute code 530, for masonry structures and 
specifications?
    The size of footings (Sec.  3285.312(c)) would depend on the load-
bearing capacity of both the piers and the soil bearing capacity. Table 
3285.312(d) and Figure 3285.312(c) would provide footing configurations 
and requirements for precast and poured-in-place concrete footings 
corresponding to specified pier loads.
    The Model Installation Standards would require support systems 
designed to combine both load-bearing capacity and uplift resistance to 
be designed and sized for all applicable design loads (Sec.  3285.313).
    These standards would not apply to installations on site-built 
permanent foundations when the manufacturer certifies the home in 
accordance with Sec.  3282.12. Otherwise, designs for permanent 
foundations (Sec.  3285.314) would also be permitted so long as designs 
are obtained from the home manufacturer, or designed by a registered 
professional engineer or registered architect. These designs may also 
be subject to more stringent or supplementary local code requirements. 
When permanent foundation designs are required, but not available from 
the home manufacturer, a registered professional engineer, or 
registered architect would need to prepare a permanent foundation 
design that satisfies the home support and anchorage requirements for 
the site and the loads for which the home was constructed.
    Foundations for homes designed for and located in areas with roof 
live loads greater than 40 psf, would be required to be designed by a 
registered professional engineer or registered architect for the 
special snow load conditions (Sec.  3285.316). The Model Installation 
Standards would also recognize the use of ramadas in areas with roof 
live loads greater than 40 pounds per square foot (psf), but would 
require that any connection to the home be for weatherproofing only.
Subpart E--Anchorage Against Wind
    Subpart E (Sec. Sec.  3285.401 and 3285.402) would provide 
requirements for anchoring necessary to secure manufactured homes 
against wind. The Model Installation Standards would require anchorage 
for manufactured home installations to be based on site conditions, 
home design features, and the loads the home was designed to withstand 
as evidenced on the data plate.
    Where applicable to the type of installation, the Model 
Installation Standards would provide requirements for determining the 
maximum spacing for anchoring assemblies, historically addressed by the 
manufacturers installation instructions. The Model Installation 
Standards would also permit alternative anchorage design as long as the 
design is verified through engineering data and designed and certified 
by a registered professional engineer or architect (Sec.  3285.401(b)), 
based on the same process for pier and footer sizing.

[[Page 21503]]

    The Model Installation Standards (Sec.  3285.402(a)) would contain 
provisions for tie-down straps and anchor assemblies including ground 
anchors for ground anchor type installations that would be consistent 
with requirements in the MHCSS (24 CFR part 3280). The resistance 
capability of anchor assemblies and anchoring equipment would be 
determined by a registered professional engineer, registered architect, 
or nationally recognized third party testing agency in accordance with 
a nationally recognized testing protocol. The anchor assemblies would 
be required to be installed in accordance with the listing and capacity 
of the anchor assembly. However, HUD is not aware of an existing 
nationally recognized testing protocol or standard established to 
determine the resistance capability of anchor assemblies and anchoring 
equipment to wind forces. While the proposed Model Installation 
Standards refer to a national test protocol as recommended by the MHCC, 
HUD is requesting comments on specific requirements that should be 
considered and contained in such a protocol. HUD notes that the 
development of a testing protocol for anchor assemblies is currently 
under review by HUD and the MHCC's installation subcommittee.
    When providing instructions or requirements for ground anchor type 
installations, the number and location of ground anchors and anchor 
straps (Sec.  3285.402(b)) for the installation of single section and 
multi-section manufactured homes would be required to consistent with 
the Tables 3285.402(c)(1) through 3285.402(c)(3), and Figures 
3285.402(b)(1) and 3285.402(b)(2). However, the tables were based on 
worst-case assumptions for current typical manufactured home 
construction and may provide conservative spacing for different design 
assumptions. The use of the tables would only be applicable under the 
limitations provided in the footnotes. It is HUD's intent that 
manufacturers or other parties may engineer and develop other anchor 
spacing for homes with characteristics that are outside of the design 
assumptions of the tables, provided that the engineered design provides 
protection to residents of manufactured homes that equals or exceeds 
the design load assumptions and protections provided by the tables when 
applied to the specific home characteristics and the design loads for 
which the home was constructed.
    Table 3285.402(c)(1) would provide the maximum ground anchor 
spacing for diagonal straps applicable to homes located in Wind Zone 1. 
However, the spacing is dependent upon the size characteristics of the 
home, the I-beam spacing, and the design capacity of the anchor 
assembly. The table also contains the maximum height from the ground to 
the strap attachment for each strap spacing, ensuring that the diagonal 
strap angle achieves a nominal 45-degree angle. The table would only be 
applicable under the limitations contained in the 12 footnotes.
    Table 3285.402(c)(2) would provide the maximum ground anchor 
spacing for diagonal straps applicable to homes located in Wind Zone 2. 
Consistent with the MHCSS (Sec.  3280.306), the Model Installation 
Standards would require a vertical strap at each diagonal strap in this 
high wind area. However, the spacing is dependent upon the size 
characteristics of the home, the I-beam spacing, and the design 
capacity of the anchor assembly. The table contains the maximum height 
from the ground to the strap attachment for each strap spacing, 
ensuring that the diagonal strap angle achieves a nominal 45-degree 
angle. The table would only be applicable under the limitations 
contained in the 13 footnotes.
    Table 3285.402(c)(3) would provide the maximum ground anchor 
spacing for diagonal straps applicable to homes located in Wind Zone 3. 
Consistent with the MHCSS (Sec.  3280.306), the Model Installation 
Standards would require a vertical strap at each diagonal strap in this 
high wind area. However, the spacing is dependent upon the size 
characteristics of the home, the I-beam spacing, and the design 
capacity of the anchor assembly. The table contains the maximum height 
from the ground to the strap attachment for each strap spacing, 
ensuring that the diagonal strap angle achieves a nominal 45-degree 
angle. The table would only be applicable under the limitations 
contained in the 13 footnotes.
    In addition to regular tie down strapping and anchoring required 
through the tables, HUD recognizes that manufacturers may provide other 
straps at the factory that must be connected to an anchoring assembly 
(Sec.  3285.403) to ensure proper anchorage of the home. Such straps 
include mate-line straps, shear wall straps, and over-the-roof straps. 
When provided by the home manufacturer, these straps must be connected 
to an anchor assembly.
    The Model Installation Standards would provide general requirements 
(Sec.  3285.404) for the installation of ground anchors in freezing 
climates and would require that anchorage for homes located within 
1,500 feet of a Wind Zone 2 or 3 coastline be specifically included in 
the home manufacturer's installation instructions. Where site or other 
conditions prohibit the use of the manufacturer's design, the anchorage 
must be designed by a registered professional engineer or registered 
architect (Sec.  3282.405) for the special wind and site or other 
conditions.
Subpart F--Optional Features
    Subpart F would provide model requirements applicable to the 
installation of optional features not otherwise covered by the Model 
Installation Standards, but which could affect the home's compliance 
with the Model Installation Standards or the MHCSS. Where applicable 
and specific to the home and product manufacturer, optional features 
such as expanding rooms (Sec.  3285.502) and some appliances (Sec.  
3285.503) would be permitted to be installed at the installation site 
provided all items are installed in accordance with the home and/or 
product manufacturer installation instructions as Home Installation 
Manual Supplements (Sec.  3285.501).
    Optional appliances (Sec.  3285.503) would be required to be listed 
(Sec.  3285.5) or certified for the intended use and must be installed 
according to the appliance manufacturer installation instructions.
    The Model Installation Standards would require heat-producing 
appliances to exhaust to the exterior of the home, beyond perimeter 
skirting if installed (Sec.  3285.503(c)). This Subpart would also 
provide minimum appliance elevation and anchoring requirements for 
homes installed in flood hazard areas (Sec.  3285.503(d)). 
Specifically, appliances would be required to be anchored, and 
appliances and air inlets elevated at or above the same elevation as 
the lowest elevation of the lowest floor of the home.
    Clothes dryer exhaust duct systems (Sec.  3285.503(e)) would be 
required to conform with and be completed in accordance with the 
appliance manufacturer instructions and the MHCSS (Sec.  3280.708).
    HUD's Model Installation Standards would contain provisions for the 
use of optional skirting (Sec.  3285.504) and corresponding crawlspace 
ventilation (Sec.  3285.505) required when a perimeter enclosure is 
installed. The ventilation requirements are consistent with 
requirements for crawlspace ventilation of other structures built to 
model building codes, and would require ventilation of 1 square foot of 
ventilation for every 150 square feet of floor area. The ventilation 
may be decreased to 1 square foot of ventilation for every 1,500 square 
feet of floor area when an acceptable vapor barrier is

[[Page 21504]]

installed according to requirements in Subpart C. Other minimum 
requirements would provide for location of vent openings and covers for 
vent openings.
Subpart G--Ductwork and Plumbing and Fuel Supply Systems
    Subpart G would provide requirements applicable to the completion 
and installation of ductwork and water, drainage, and fuel supply 
systems. The provisions of subpart G are necessarily limited in scope 
and content, but are required to ensure that the manufactured home is 
not taken out of compliance with the MHCSS after installation is 
completed. The connections of the systems to utilities are located in 
subpart J of the proposed rule.
    Work related to completion of these systems at the installation 
site is deemed to be installation work so long as the work is limited 
only to that necessary to join sections of a multi-section home. 
However, the home manufacturer consistent with the existing 
requirements of the MHCSS must design instructions for completion of 
this work.
    Home manufacturers would be required to provide specific written 
instructions on the proper assembly for ship loose plumbing, duct, and 
fuel supply systems that are necessary to join all sections of a multi-
section home (Sec.  3285.601). The home manufacturer must design 
instructions to ensure that the systems, upon completion, will conform 
to the requirements of the MHCSS and the Model Installation Standards.
    The Model Installation Standards would require water line 
crossovers (Sec.  3285.603) for multi-section homes to be designed in 
accordance with provisions of the MHCSS (Sec.  3280.609). In addition, 
the Model Installation Standards would establish requirements for water 
supply inlet pressure consistent with the MHCSS, and establish a 
requirement for a mandatory shut-off valve. The Model Installation 
Standards would also require that water lines exposed to freezing 
temperatures be protected from freezing in accordance with requirements 
already established by the MHCSS (Sec.  3280.603). The water system 
would also need to be tested for leaks after completion at the 
installation site with testing requirements consistent with the MHCSS 
(Sec.  3280.612).
    The Model Installation Standards would require drainage crossovers 
(Sec.  3285.604) for multi-section homes to be designed in accordance 
with provisions of the MHCSS (Sec.  3280.610). In addition, the Model 
Installation Standards would establish requirements for proper drainage 
line support and slope, also consistent with the requirements of the 
MHCSS (Sec.  3280.608). The drainage system would also need to be 
tested for leaks after completion at the installation site with testing 
requirements consistent with the MHCSS (Sec.  3280.612).
    The Model Installation Standards would require fuel supply 
crossovers (Sec.  3285.605) for multi-section homes to be designed in 
accordance with provisions of the MHCSS (Sec.  3280.705). In addition, 
the Model Installation Standards would establish requirements for 
proper fuel supply pressure, consistent with the MHCSS and a 
requirement for a mandatory shut-off valve. The fuel supply system 
would also need to be tested for leaks after completion at the 
installation site with testing requirements consistent with the MHCSS 
(Sec.  3280.705).
    Subpart G would also provide requirements for duct crossovers and 
the materials to be used in completing the crossover connections (Sec.  
3285.606). Typical duct crossover designs are illustrated in figures 
and are consistent with current manufacturer installation instructions. 
However, other types of duct crossovers would be permitted so long as 
the crossover is adequately insulated and properly designed for the 
application.
Subpart H--Electrical Systems and Equipment
    The Model Installation Standards would require instructions for 
completing electrical crossovers (Sec.  3285.701) to be designed 
consistent with subpart I of the MHCSS. The Model Installation 
Standards would also provide specific requirements for the installation 
of certain lights and fixtures, including chain-hung interior lights, 
exterior lights and ceiling suspended paddle fans.
    Subpart H would also contain testing requirements for electrical 
continuity, operation, and electrical polarity after completion of the 
electrical system at the installation site. Testing requirements would 
include functionally testing smoke alarms after completion of the home 
(Sec.  3285.703).
    There may be information currently addressed by manufacturer 
installation instructions that has not been evaluated by the MHCC or 
reviewed for inclusion in the Model Installation Standards. Such issues 
as multi-section frame bonding, panel box grounding, and electrical 
feeder requirements may need further consideration. Therefore, HUD 
specifically invites public comment on the substance of this Subpart H 
and other related issues that should or should not be addressed.
Subpart I--Exterior and Interior Close Up
    Subpart I would establish Model Installation Standards applicable 
to work related to the joining of all sections of a multi-section home. 
Section 3285.801 would establish provisions for close up of the 
exterior of the home and would include exterior siding and roofing. 
Exterior products would be required to be installed in accordance with 
the product manufacturer's installation instructions and fastened in 
accordance with manufacturer designs consistent with the MHCSS 
(Sec. Sec.  3280.305 and 3280.307). The Model Installation Standards 
also address completion of an air seal gasket around the mate-line of 
multi-section homes to prevent the infiltration of air, water, insects, 
and vermin. The Model Installation Standards would also contain 
reference to hinged roofs and eaves. Under this proposed rule, 
unpenetrated, low-slope hinged roofs would be covered by the 
requirements for installation instructions and exterior close-up work. 
Other, more complex hinged roofs would continue to be subject to 
requirements established under the MHCSS. The Department addressed 
those requirements in a draft rule on on-site construction that it 
submitted to the MHCC for its prepublication review. Should the Model 
Installation Standards retain the proposed distinction (Sec.  
3285.801(f)) for certain hinged roofs that would permit completion of 
those roofs under the Federal installation program as part of exterior 
close-up? Or should all hinged roofs, regardless of roof slope, 
location, or penetration, be uniformly treated as construction of the 
roof assembly of the home and therefore subject to requirements related 
to the MHCSS? However, hinged roofs may be subject to Alternative 
Construction or other requirements to be outlined in an on-site 
construction rule to be published for comment separately by HUD.
    The Model Installation Standards would provide requirements 
relating to the structural interconnection of multi-section homes 
(Sec.  3285.802). These provisions would include requirements to 
maintain the structural integrity of the home and would establish 
requirements for gaps that may occur at the mate-line upon 
installation.
    The Model Installation Standards would also provide requirements 
for the interior finishing of certain aspects of the home that would 
not be completed at the factory due to transportation

[[Page 21505]]

limitations or possible transit damage (Sec.  3285.803). Section 
3285.804 would provide for repair of bottom board material that may be 
disturbed during the installation process.
Subpart J--Recommendations for Manufacturer's Installation Instructions
    Generally, moving manufactured homes and completing work at the 
site with respect to utility connections are subject to LAHJ 
requirements. Therefore, the proposed Model Installation Standards do 
not attempt to comprehensively address transport, permits, and utility 
connection requirements. However, several related provisions are 
included in subpart J as recommendations for manufacturers to include 
in their installation instructions in order to protect manufactured 
homes as constructed in accordance with the MHCSS (Sec.  3285.901).
    Specifically, Subpart J would provide recommendations for 
manufacturers to provide instructions related to moving the 
manufactured home to the installation site (Sec.  3285.902), fire 
separation, construction of on-site structures (Sec.  3285.903), 
provisions for culverts and ditches (Sec.  3285.904), connection of the 
drainage system to the sewer system (Sec.  3285.905), as well as 
installation instructions for fuel system orifices and regulators and 
gas appliance startup procedures.
    Subpart J would also address heating oil systems and tank 
installation (Sec.  3285.906), recommending that work be completed in 
accordance with the more stringent requirements of the LAHJ or the 
nationally recognized consensus standard NFPA 31.

II. Summary of Changes to MHCC Proposed Installation Standards

    In general, HUD's Model Installation Standards incorporate the vast 
majority of the MHCC's proposed installation standards but would amend 
the MHCC proposal for consistency with format and numbering of 
regulations published in the Code of Federal Regulations. HUD's Model 
Installation Standards would also delete all references to SI (metric) 
units because they were not consistently and comprehensively identified 
within the MHCC recommendations and have not been adopted by HUD in all 
other standards publications.
    In instances of other modification, HUD made a good-faith attempt 
to retain the intent and text of the installation standards provided by 
the MHCC. However, editorial changes have been made in the text for 
consistency with formatting of Federal Register documents, or for 
clarification purposes. In most areas where a change is being 
recommended for editorial or clarification purposes, it is not 
described with an associated rationale. In some instances, HUD 
recommends new or revised Model Installation Standards to replace the 
MHCC's proposed installation standards. These instances are fully 
described. HUD summarizes its changes to the MHCC proposal by grouping 
the changes into the following general categories:
     Consistency--HUD modified certain installation standards 
proposed by the MHCC to retain consistency with the Act, other sections 
of the Model Installation Standards, the MHCSS (24 CFR part 3280) and 
the Manufactured Home Procedural and Enforcement Regulations (24 CFR 
part 3282). Some changes for consistency would require a companion 
change to part 3280 and are identified appropriately.
     Relocate--HUD relocated certain sections or portions of 
text within the document while attempting to preserve the MHCC's 
installation standards and intent.
     Authority--HUD revised or deleted certain sections of the 
MHCC's proposed installation standards because the proposed 
installation standard was not within the scope of HUD's authority, or 
in the opinion of HUD, is an aspect of home installation best retained 
by the States for regulation through an LAHJ. In some instances, HUD 
retained such provisions in the Model Installation Standards but moved 
them from the MHCC proposed location and placed them in a section 
containing recommendations for inclusion in manufacturer installation 
instructions.
     Construction--HUD also modified certain MHCC-proposed 
installation standards that address completion of some aspects of the 
manufactured home at the site. HUD removed certain of these provisions, 
as they would be regulated under Alternative Construction requirements 
or other requirements for site completion to be published separately by 
HUD based upon consultation with the MHCC.
     Procedural--HUD revised or otherwise modified certain 
provisions because they did not establish standards but rather provided 
procedural direction. HUD will further consider these provisions in its 
future development of the Federal Installation Program regulations.
     Technical--HUD modified other provisions of the MHCC's 
proposed installation standards due to differences that are technical 
in nature.

Subpart A--General

    Subpart A incorporates portions of chapters 1, 2, 3, and 4 of the 
MHCC's proposed installation standards. Subpart A sets forth provisions 
for administration, referenced publications, and definitions of terms 
used throughout the document. However, HUD has made certain 
modifications to the MHCC's proposal as outlined below.
Administration Sec.  3285.1
    Scope (Relocate, Technical)--HUD revised the scope of the Model 
Installation Standards from that proposed by the MHCC to emphasize 
certain parameters relating to the use and requirements of the document 
within the envisioned Federal installation program. The scope statement 
submitted by the MHCC provided direction on the use of manufacturer 
installation instructions but did not provide information relating to 
the use of the Model Installation Standards in the more general context 
of HUD's installation program which will be established by separate 
rulemaking. Therefore, HUD modified the scope of the document to 
emphasize the following:
     The Model Installation Standards, as enforced under the 
Federal manufactured home installation program, would be applicable 
only to the first or initial installation of new manufactured homes. 
The use of these standards for any other manufactured home installation 
would be subject to State or local law.
     HUD has proposed a distinction between construction and 
installation work for the purposes of this proposed rule. 
Traditionally, work necessary to join the sections of a multi-section 
home has not been fully enforced by HUD or State or local agencies as 
part of the construction and assembly process or the installation 
process. Through this proposed rule, HUD would continue to recognize 
the current practice that installers accomplish certain work, limited 
to the joining of sections, as installation work completed at the 
installation site because of the impracticality of completing the work 
at the factory. However, home manufacturers would be accountable and 
responsible to furnish with each new home, adequate instruction on the 
completion of these joining and crossover aspects. The installer or 
retailer would be accountable and responsible to complete the work in 
accordance with the instructions provided and/or instructions developed 
by registered professional engineers or

[[Page 21506]]

architects in instances indicated in the Model Installation Standards.
     HUD has also added language that outlines the use of the 
Model Installation Standards in both States that choose to operate 
their own installation programs as well as the intended use of the 
document in States that do not choose to operate an installation 
program.
     The MHCC's language relating to manufacturer installation 
instructions has been preserved and relocated with modification, at 
Sec.  3285.2.
    Applicability (Consistency, Technical)--HUD accepted the intent of 
the MHCC's proposal for applicability of the Model Installation 
Standards. However, HUD modified the MHCC's proposed applicability 
sections to simplify the requirements for convenience and clarity. In 
summary, the Model Installation Standards would apply only to new 
manufactured homes produced under the Federal Manufactured Housing 
Program (24 CFR part 3280 and 24 CFR part 3282). As provided by section 
604(f) of the Act (42 U.S.C. 5403(f)), the installation standards do 
not apply to homes installed on site-built permanent foundations when 
the manufacturer certifies the home in accordance with Sec.  3282.12. 
Exclusions and other restrictions proposed by the MHCC were not deemed 
necessary by HUD, and therefore have been omitted.
    Installation of Manufactured Homes in Flood Hazard Areas 
(Relocate--Sec.  3285.101)--HUD accepted the MHCC's recommended 
provisions relating to home installation in flood hazard areas. 
However, HUD relocated the requirements for flood hazard areas, with 
minimal revisions, to Subpart B for inclusion as a pre-installation 
consideration.
    Manufacturer Installation Instructions Sec.  3285.2 (New Section--
Technical, Consistency)--HUD accepted the intent of the MHCC in its 
proposed scope language and definition of manufacturers instructions. 
However, section 605(a) of the Act (42 U.S.C. 5404(a)) contains 
specific provisions for installation design and instructions. 
Therefore, HUD established a new section in the Model Installation 
Standards requiring manufacturer installation instructions be provided 
with each new home. Manufacturer installation instructions, as set 
forth in section 605(a) of the Act, must meet or exceed the protection 
provided under the Model Installation Standards and would need to 
address, at a minimum, the requirements of the Model Installation 
Standards.
    HUD preserved a majority of the language and intent provided the 
MHCC in its scope statement, and supplements the language provided by 
the MHCC in its definition of installation instructions. HUD also 
modified this section to provide that the manufacturer's installation 
instructions must not take the home out of compliance with 24 CFR part 
3280.
    HUD invites comment concerning whether manufacturer installation 
instructions should provide that when general site conditions are not 
covered by the installation instructions, a professional engineer or 
registered architect must be consulted.
    Term Use (Consistency)--HUD did not accept this MHCC proposal 
because the Model Installation Standards are applicable only to 
manufactured homes as fully described in the Applicability section 
(Sec.  3285.1(d)).
    Alterations During Initial Installation Sec.  3285.3 (New Section--
Technical, Relocate)--HUD's Model Installation Standards include a 
section to address alterations made during the initial installation of 
a new manufactured home that affect the installation of the home. The 
Federal installation program would provide for design and inspection 
authority for modifications to a home or foundation only when the 
alteration affects the requirements of the Model Installation Standards 
or the MHCSS. State or local authority would have design and inspection 
authority for other alterations.
    HUD acknowledges that there are questions in delineating State or 
local authority from Federal jurisdiction in instances related to 
alterations during initial installations, such as for patio roofs, 
decks, entry stairs, etc. HUD specifically invites comment as to how 
alterations made to manufactured homes that affect the installation or 
designed foundation during the initial installation should be enforced 
and codified.
    Referenced Publications Sec.  3285.4 (Consistency, Technical)--HUD 
accepted the vast majority of referenced publications provided by the 
MHCC. However, HUD modified the order and sequence of certain standards 
incorporated by reference and is adding to or did not include some 
standards included in the MHCC proposal as follows:
    ACCA Manual J: HUD added this reference standard in Subpart F 
because it is a nationally recognized standard for sizing air 
conditioning equipment and is currently utilized and accepted by all 
parties for this purpose.
    ASTM D1586: HUD added this nationally recognized consensus standard 
as a method of determining soil characteristics consistent with the 
current work of the MHCC's ground anchor task force.
    ASTM D2487: HUD added this nationally recognized consensus standard 
as a method of determining soil classification consistent with the 
current work of the MHCC's ground anchor task force.
    ASTM D2488: HUD added this nationally recognized consensus standard 
as a method of determining soil classification consistent with the 
current work of the MHCC's ground