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FAQs for Manufactured Home Construction and Safety Standards, 3rd Set Final Rule (EFFECTIVE JULY 12, 2021)

The statements in these general responses to questions are not intended to provide specific HUD guidance or direction related to compliance with the Construction & Safety Standards and do not waive any requirement presented in the rules or other interpretations issued by HUD.  Any specific concern related to an actual report or inspection can be directed in the manner set forth in the published rules.  HUD will review monitoring reports to assess compliance and need for any future clarification to the stakeholders.


24 CFR § 3280.5 Data Plate

1)  3280.5(d) has been modified to require our data plate to specify that a home IS or IS NOT designed to accomodate additional loads from a site-attached building.  Does this sound correct?

Yes. Additionally, see 3282.601(c) Exception.


24 CFR § 3280.11 Certification Label

2)  3280.11(d) has been revised to address possible site additions that prevent the location of the label as specified in the standards.  When the label is being relocated, does the location need to be specified by the DAPIA?  

The Certification Label shall be affixed in a location that is in accordance with an approved design and accommodates any DAPIA-approved On-Site Completion of Construction or Alternative Construction letters.  The rule change requires that the Certification Label be affixed in a location that will remain visible after all work that is necessary to complete the installation of the home, at the home site.  Note that relocation of a Certification Label is not required or authorized under the existing rules or addressed by this section.  This revised rule clarifies the specific location of the factory-affixed Certification Label and applies to any Date of Manufacture on or after the effective date of the final rule.


24 CFR § 3280.103 Light and Ventilation

3)  3280.103 (b) has been updated to eliminate the necessity of having homes built under an AC approval when exceeding 90 CFM.  This is achieved by using the method as specified in ASHRAE 62.2.  Am I understanding this correctly?

No, 3280.103(b) was revised to simply eliminate the previous codified maximum ventilation capacity of 90 CFM. This would eliminate the need for Alternative Construction for homes over 2,571 square feet. 

In addition, and independent of that change, ASHRAE 62.2 is being added as an optional method to demonstrate compliance in lieu of 3280.103(b) and 3280.103(c).


24 CFR § 3280.113 Glass and Glazed Openings

4)  3280.113(b) specifies glazed openings on porches.  Is this requiring safety glazing on porches that are 65% open and unobstructed that face the street, yard or court?

This is a new paragraph that is not affecting the requirements for safety glazing (i.e., safety glazing requirements would be redesignated as 3280.113(c)). This new paragraph is designed to allow glazed window openings in areas facing a roofed porch to meet light and ventilation requirements, so long as all other requirements of the new 3280.113(b) are met.


24 CFR § 3280.114  Stairways

5)  In 3280.114 Stairways, please clarify how to comply with one (1) candle-foot measured at the center of treads and landings.

The standards are performance-based and as such compliance remains, as with all other standards, the responsibility of the home manufacturer.  This may be demonstrated, although not exclusively, through test or inspection or both. There are various methods and tools available to measure light intensity by candle-foot. Generally, the manufacturer's chosen method is evidenced via a specific design approval indicating its limitations and applicability, including through a special quality control procedure.


24 CFR § 3280.211 Carbon Monoxide Alarm Requirements

6)  In 3280.211(b), does every home that contains a fuel burning appliance or that is designed to include an attached garage require a carbon monoxide alarm? 



24 CFR § 3280.305 Structural Design Requirements

7)  3280.305(h)(5) was added to specifically address unfinished roof assembly installation and inspection under Subpart M.  This does not specify that this applies to roofs at or exceeding 7:12 roof pitch as noted in 3285.801.  Does this now apply to all hinged roofs including those that are less than 7:12 roof pitch?

The provisions included in new paragraph 3280.305(h)(5) are intended to provide more specifics and allowance regarding what may be completed under Subpart M but does not change the exceptions of On-Site Completion of Construction approvals, such as those already identified in the Model Manufactured Home Installation Standards at 24 CFR 3285.801(f); specifically, (2) indicates that homes with a roof pitch of the hinged roof less than 7:12 are exempt from IPIA final inspection and are to be completed and inspected in accordance with the Manufactured Home Installation Program (24 CFR part 3286).


24 CFR § 3280.602 Definitions

8)  In 3280.602 Definitions, please clarify what a suitable air gap is.

Please see 24 CFR 3280.604(b) that incorporates reference ASME standard A112.1.2–1991, Air Gaps in Plumbing Systems.


24 CFR § 3280.609 Water Distribution Systems

9)  3280.609(c)(1)(iii) requires the relief valve drain to be installed to the exterior of the home and not under the home.  This will mean that these must be plumbed out the rim, skirting or foundation wall and directed downward and terminate between 6” and 24” above finished grade, correct?

Yes. Note that 3280.609(c)(1)(iv) does not require the under-floor relief valve piping to be completed in the factory.


24 CFR § 3280.611 Vents and Venting

10)  3280.611(c)(1)(ii) has been revised to say that a 3” drain section wet vented through a 2” vent is permitted to carry the waste of an unlimited number of fixtures.  Will this mean that the branch that is wet vented can carry the waste of multiple fixtures while still venting the stool?



24 CFR § 3280.612 Tests and Inspections

11)  3280.612(a) has been revised to lower the testing pressure to 80 psi +/- 5 psi and to test with potable water, correct?



24 CFR § 3280.705 Gas Piping Systems.

12)  3280.705 (l)(8)(i) was revised to add a +/- 0.2 psi allowance, correct?



13)  3280.705 (l)(8)(iii) added a section to clarify crossover connections, installation instructions and testing.  Manufacturers should make sure that these instructions are included with the home, correct?



24 CFR § 3280.709  Installation of Appliances

14)  In 3280.709(a)(1) Installation of direct vent space heating appliance in basement, is this potentially an On-Site Construction approval?

On Site Completion of Construction includes heating appliances to be installed on site, per 24 CFR 3282.602(a)(3). 


24 CFR § 3280.710  Venting, Ventilation, and Combustion Air

15)  3280.710 (d) has been revised to add the provision to locate the venting of fuel burning appliances when located within 10 feet of a motor driven air intake to be located 3 feet above the intake, correct?



24 CFR § 3280.807  Fixtures and Appliances

16)  3280.807 (g) is a new provision that requires a separate switch for each light when provided with a wall light and a ceiling light in a bathroom, correct?



24 CFR § 3280.904  Specific Requirements for Designing the Transportation Systems

17)  3280.904 (b)(9)(ii) has been revised to reflect a braking distance of 35 feet from the previous requirement of 40 feet. Will this require us to perform a transportation test?

Yes, unless current brake performance tests demonstrate service brake system compliance with a 35-feet braking distance.


24 CFR § 3282.14  Alternative Construction

18)  How will the new rules affect AC letters on two-story homes and homes with attached garages?  Currently our company is assuming that structurally independent garages no longer require an AC letter.  Do two story homes and structurally dependent garages remain the same or do these homes require an On-Site Completion (SC) approval?

Upon the effective date of the Standards changes, all homes, including two-story manufactured homes, completed with the addition of a garage will no longer require a HUD-issued Alternative Construction letter so long as the garage is either: (1) structurally independent, with any attachment between the home and the garage serving a weatherproofing or cosmetic purpose only, or,  (2)structurally dependent but meeting the requirements for an attached accessory building or structure that is not structurally independent as set forth in 24 CFR 3282.8(j)(2).

Generally, these homes would also not require an On-Site Completion of Construction approval but that will depend upon the design and installation instructions.  Should a DAPIA and or IPIA have questions in this regard, it should consult with HUD prior to approval.