74 [107 Op. Att’y

BUILDING CODES

MANUFACTURED HOMES – FIRE SPRINKLERS – WHETHER 

STATE LAW REQUIRES FIRE SPRINKLER SYSTEMS TO BE 

INSTALLED IN MANUFACTURED HOMES – WHETHER 

FEDERAL LAW WOULD PREEMPT SUCH A REQUIREMENT

March 2, 2022

The Honorable Joseph M. Mitrecic

President, Board of County Commissioners of Worcester County

You have asked whether Maryland law requires the 

installation of fire sprinkler systems in manufactured homes. 

Manufactured homes, which are built in factories and transportable 

on wheels, are constructed in compliance with regulations 

developed by the U.S. Department of Housing and Urban 

Development (“HUD”). Although a manufactured home might 

have a fire sprinkler system, federal law does not require one. 

Maryland statutes enforced by the State Fire Marshal do require the 

installation of fire sprinklers in certain types of buildings. But last 

year, the State Fire Marshal issued informal guidance opining that 

while Maryland law requires installation of fire sprinklers in most 

types of one- and two-family homes, it does not require them in 

manufactured homes.

We agree with the State Fire Marshal that State law does not 

currently require the installation of fire sprinklers in manufactured 

homes. As an initial matter, although the federal statute that grants 

HUD authority over manufactured homes contains an express 

preemption provision, it would not preempt a state or local 

requirement that manufactured homes be equipped with fire 

sprinklers. The federal statute provides that state and local 

governments can impose additional requirements on manufactured 

homes where HUD’s regulations are silent, and HUD’s regulations 

are silent on fire sprinklers.

While the State could mandate fire sprinklers in manufactured 

homes, neither the General Assembly nor the Maryland 

Department of Labor (“DOL”), which maintains the State’s 

building codes and administers the State’s regulatory program for 

manufactured homes, has done so. The statewide building 

standards administered by DOL—known as the Maryland Building 

Performance Standards (“MBPS”)—do require fire sprinklers in 

those homes that they govern. But neither the statute adopting the 

MBPS nor the MBPS regulations evince an intent to apply to 
Gen. 74] 75

manufactured homes. Rather, the State has consistently 

maintained a separate statutory and regulatory scheme for 

manufactured homes. That is likely because a detailed regulatory 

code—the HUD standards—already existed for manufactured 

homes when the General Assembly established the MBPS. The 

purpose of the MBPS, instead, was to regulate traditional “sitebuilt” buildings, including site-built homes, which had previously 

been subject to a patchwork of inconsistent local requirements. 

Notably, both the State Fire Marshal and the Maryland 

Department of Housing and Community Development (“DHCD”) 

(DOL’s predecessor as building regulator) have also concluded that 

the MBPS sprinkler requirement does not govern manufactured 

homes. We owe considerable deference to interpretations of 

statutes by the agencies charged with administering them. For all 

of these reasons, we conclude that the language of the MBPS 

statute and regulations, which does not specifically address 

manufactured homes, was not intended to cover them. Thus, no 

provision of Maryland law currently requires fire sprinklers in 

manufactured homes. 

I

Background

A. Manufactured Homes

A manufactured home is a single-family home that is built in 

a factory on a wheeled chassis, then towed to the site where it will 

be used as a house. Maryland Dep’t of Labor, Building Codes 

Admin., What Is a Modular and a Manufactured (Mobile) Home?, 

https://www.dllr.state.md.us/labor/build/buildmoddef.shtml (last 

visited Feb. 25, 2022). Once the home arrives on site, installers 

normally remove the wheels, then connect it to utilities and 

stabilize it in place. See James Milton Brown & Molly A. Sellman, 

Manufactured Housing: The Invalidity of the “Mobility” Standard, 

19 Urb. Law. 367, 376 (1987). Manufactured homes are 

sometimes called “mobile homes.” Id. at 371. But that term is 

often a misnomer: though a manufactured home once placed can 

in theory be moved again, that rarely happens in practice, due to 

high moving costs and limited options for placement. Amy J. 

Schmitz, Promoting the Promise Manufactured Homes Provide for 

Affordable Housing, 13 J. Affordable Housing & Community Dev. 

L. 384, 385, 389 (2004). Manufactured homes are frequently, but 

not always, placed in parks where the residents own their homes 

but rent the underlying land from the park owner. Id. at 388. In 

2017, there were 39,300 manufactured homes in Maryland (about 
76 [107 Op. Att’y

2% of the State’s total housing stock), and since then, 

approximately 100 new units per year, on average, have been 

shipped to Marylanders.1

HUD is the primary regulator of manufactured home design 

and construction under the National Manufactured Home 

Construction and Safety Standards Act, 42 U.S.C. §§ 5401-5426 

(the “Federal Act”). Congress charged HUD with ensuring that 

manufactured homes are durable and safe but also affordable and 

subject to nationally uniform standards. 42 U.S.C. § 5401. To 

those ends, HUD promulgates and maintains the “Federal 

Manufactured Home Construction and Safety Standards” (the 

“HUD standards”). 24 C.F.R. pt. 3280. The HUD standards 

regulate aspects of the manufactured home including minimum 

room size; light and ventilation; structural integrity; insulation; 

plumbing, heating, cooling, and electrical systems; and fire safety. 

See id. Inspectors certified under HUD’s authority approve each 

manufactured home design for compliance with these standards 

and oversee construction at each factory. 24 C.F.R. §§ 3282.203, 

3282.204, 3282.361, 3282.362. These inspectors issue “HUD 

labels” which manufacturers attach to each home to certify 

compliance with the HUD standards. Id. § 3282.205, 3282.362. 

The Federal Act prohibits the sale of a new manufactured home 

without a HUD label. See 42 U.S.C. § 5409.

The Federal Act preempts state and local regulation of any 

“aspect of [manufactured home] performance” that the HUD 

standards address. Id. § 5403(d). But the Act also expressly 

recognizes that states can regulate “any manufactured home 

construction or safety issue” where no HUD standard applies. Id.

§ 5422(a). The Act also allows a state to take over enforcement of 

the HUD standards as a delegate of HUD, subject to the same 

preemption rules. See id. § 5422(b). Within Maryland, DOL 

oversees enforcement of the HUD program, having taken over that 

role from DHCD in 2018. Md. Code Ann., Pub. Safety (“PS”) 

§ 12-312; 2018 Md. Laws, ch. 673.

B. Other Types of Single-Family Homes

Other statutory and regulatory schemes govern the design and 

construction of other types of homes. A “site-built” or “stick-built” 

1

See U.S. Census Bureau, American Housing Survey, Maryland—General 

Housing Data (2017), https://www.census.gov/programs-surveys/ahs.html; 

U.S. Census Bureau, Manufactured Housing Survey, Shipments of New 

Manufactured Homes (2021), https://www.census.gov/data/tables/timeseries/econ/mhs/shipments.html.
Gen. 74] 77

home is constructed in the traditional manner—from scratch, on the 

site where it will permanently stand. In Maryland, local 

governments are the primary regulators of site-built homes, 

although, as we will explain, the State has attempted to balance that 

local autonomy with uniform statewide standards. See PS §§ 12-

502 to 12-505.

Originally, the regulation of site-built home construction was 

exclusively a matter for local governments, which focused on 

preventing fires. 5 Philip L. Bruner & Patrick J. O’Connor, Jr., 

Construction Law § 16:2 (Aug. 2021 update). For example, a 1799 

Baltimore City ordinance prohibited the construction of wooden 

buildings in the City center. Baltimore City Ord. No. 22 (June 11, 

1799). Over time, as construction techniques grew more complex 

and builders adopted more dangerous technologies, regional and

national standard-setting organizations began to develop model 

building codes, which local and state governments would then 

adopt. Bruner & O’Connor, supra, § 16:2. Local jurisdictions in 

Maryland adopted a variety of model codes—with the Building 

Officials and Code Administrators (“BOCA”) Code as the most 

popular—and some continued with no code at all. Report of the 

Maryland Building Performance Standards Task Force 3 (1993) 

(“MBPS Report”); 1993 Md. Laws, ch. 200 (Preamble).

To clear away this regulatory tangle, the General Assembly in 

1993 directed DHCD to establish by regulation a new statewide 

building code: the Maryland Building Performance Standards. 

1993 Md. Laws, ch. 200 (enacting Art. 83B, §§ 6-401 to 6-406, 

now codified as amended at PS §§ 12-501 to 12-510). The new 

MBPS regulations were based on the BOCA Code and 

incorporated it by reference. Id. (enacting Art. 83B, § 6-402, now 

codified as amended at PS § 12-503). The MBPS statute required 

each local jurisdiction to use the MBPS as its building code but 

allowed local governments to adopt local amendments to the 

MBPS regulations, including amendments establishing different or 

less stringent standards. See id. (codified as amended at PS §§ 12-

503 and 12-504). Thus, each MBPS provision applies in each 

jurisdiction unless the local government opts out of a particular 

requirement. The State also continued to leave building code 

enforcement to localities. Id. (codified as amended at PS § 12-

502(c)). In 2000, several standard-setting organizations merged 

into the International Codes Council, and the new International 

Building Code superseded the BOCA Code. See 2000 Md. Laws, 

ch. 39.
78 [107 Op. Att’y

Today, the MBPS regulations incorporate several 

International Codes, each regulating a different constructionrelated subject. COMAR 09.12.51.04. Most relevant here, the 

International Residential Code (“IRC”) sets standards for the 

design and construction of one- and two-family homes.2 When the 

International Codes Council updates one of these model codes 

(which normally happens every three years), the Department of 

Labor must update the MBPS within eighteen months, though the 

agency has some discretion to make modifications to the codes 

before adopting each version as part of the MBPS. PS § 12-503.

“Modular homes” make up a third category distinct from both 

manufactured and site-built homes. Modular homes are built in a 

factory (often in multiple sections) like a manufactured home, but 

they are designed to be installed on a permanent foundation and 

never moved again, like a site-built home. What Is a Modular and 

a Manufactured (Mobile) Home?, supra. HUD does not regulate 

modular homes. See 42 U.S.C. § 5403(f). In Maryland, modular 

homes are classified as “industrialized buildings,” which are 

subject to a set of DOL regulations that is based on, but separate 

from, the MBPS. See PS §§ 12-301(d), 12-305. However, the 

industrialized building regulations incorporate many of the same 

model code provisions by reference, which means that in substance 

modular homes, like site-built homes, are mainly governed by the 

International Residential Code. See COMAR 09.12.50.02-1, 

09.12.52.06, 09.12.52.07. 

C. Fire Sprinklers

The question of whether to mandate the installation of fire 

sprinklers in new buildings, especially single-family homes, has 

been the subject of frequent policy debates in recent years. A fire 

sprinkler system consists of sprinkler heads in various rooms of a 

building, connected to pressurized water pipes. If the air temperature 

around a sprinkler head reaches a certain level, indicating that there 

is a fire in the room, that sprinkler head opens and sprays water to 

extinguish the fire or at least suppress it long enough for the 

building’s occupants to escape and for firefighters to arrive.3

2 All HUD-regulated manufactured homes are single-family homes. 

See 24 C.F.R. § 3282.8(l).

3 Nat’l Fire Protection Ass’n, How Home Fire Sprinklers Work, 

https://www.nfpa.org/Public-Education/Staying-safe/Safetyequipment/Home-fire-sprinklers/Fire-Sprinkler-Initiative/Takeaction/Free-downloads/How-sprinklers-work (last visited Feb. 25, 

2022).
Gen. 74] 79

Proponents of mandated fire sprinkler installation argue that 

fire sprinkler systems dramatically reduce house-fire deaths among 

civilians and firefighters.4 For example, as of 2020, Prince 

George’s County had not recorded a single fire death in a home 

with a functioning sprinkler system for nearly thirty years, 

compared to an average of ten fire deaths per year in homes without 

sprinklers. Hearing on H.B. 823 Before the House Env’t & Transp. 

Comm., 2020 Leg., Reg. Sess. (Feb. 25, 2020) (written testimony 

of the Prince George’s County Executive). Opponents contend, 

however, that sprinkler systems are costly to install and that 

mandating them across the board could impair the availability of 

affordable housing. See, e.g., Hearing on S.B. 602 Before the 

Senate Educ., Health, & Env’tl Affairs Comm., 2012 Leg., Reg. 

Sess. (Feb. 28, 2012) (written testimony of the Caroline County 

Commissioners).

In 2008, the International Codes Council amended the 

International Residential Code to mandate fire sprinklers in those 

new one- and two-family homes covered by the IRC. ICC 

Approves Sprinkler Requirement in Family Dwellings, 32 

Construction Cont. L. Rep. 247 (Nov. 6, 2008). The IRC’s new 

sprinkler mandate took effect in Maryland on January 1, 2011, after 

DHCD updated the MBPS regulations to incorporate the new Code 

version. 36:16 Md. Reg. 1255, 1255 (July 31, 2009). Several local 

governments then exercised their local amendment authority to opt 

out. See PS § 12-504; Revised Fiscal & Policy Note for H.B. 366, 

2012 Leg., Reg. Sess. The General Assembly responded in 2012 

by prohibiting local governments from opting out of the MBPS 

sprinkler mandate. 2012 Md. Laws, chs. 265, 266 (enacting PS 

§ 12-504(a)(1)(iii)). In 2020, the General Assembly, concerned 

that some jurisdictions were still not enforcing the sprinkler 

mandate, transferred responsibility for its enforcement to the State 

Fire Marshal. 2020 Md. Laws, ch. 334 (enacting PS § 6-305(a)(3)); 

Hearing on H.B. 823 Before the House Env’t & Transp. Comm., 

2020 Leg., Reg. Sess. (Feb. 25, 2020).

None of these statutory and regulatory amendments addressed 

whether or how the sprinkler mandate would apply to 

manufactured homes. A 2017 memorandum issued by DHCD 

concluded that State law does not currently require fire sprinklers 

in manufactured homes. Memorandum from Norman C. Wang, 

Director, Maryland Codes Administration, to Maryland Local 

Building Officials and the Office of the Maryland State Fire 

4

See Marty Ahrens, Nat’l Fire Protection Ass’n, U.S. Experience With 

Sprinklers (Oct. 2021), https://www.nfpa.org/News-and-Research/Dataresearch-and-tools/Suppression/US-Experience-with-Sprinklers.
80 [107 Op. Att’y

Marshal (Aug. 11, 2017) (“Wang Memorandum”). And in 2021, 

the State Fire Marshal also opined that State law requires sprinklers 

in new one- and two-family site-built and modular homes but not 

in manufactured homes. Office of the State Fire Marshal, 

Requirements for Automatic Residential Fire Sprinkler Systems in 

One- and Two-Family Dwellings (May 17, 2021) (“Fire Marshal 

Memorandum”). But we have not previously addressed this issue.

II

Analysis

To answer your question, we first consider whether the 

preemption provision in the Federal Act that applies to 

manufactured homes would bar Maryland from imposing a fire 

sprinkler requirement on such homes. We conclude that it would 

not, because while the HUD standards address some aspects of fire 

safety, they do not address fire sprinklers or fire suppression more 

generally. We also conclude, however, that Maryland law does not 

currently apply a fire sprinkler mandate to manufactured homes. 

The Maryland Building Performance Standards—the source of the 

State’s fire-sprinkler mandate for one- and two-family homes—

were not intended to govern manufactured homes, which have had 

their own regulatory regime since before the MBPS took effect.

A. Federal Preemption

The Federal Act governing manufactured homes is structured 

to balance national uniformity with state and local autonomy. The 

statute preempts state and local law governing manufactured home 

construction and safety, but only when it addresses an “aspect of 

performance” that the HUD standards also address. See 42 U.S.C. 

§§ 5403(d), 5422(a). As we will explain, because the HUD 

standards address fire safety generally but not fire sprinklers in 

particular, the Federal Act would not preempt a state or local fire 

sprinkler mandate.

Federal law can preempt state law in one of three ways. See 

Kansas v. Garcia, 140 S. Ct. 791, 801 (2020). First, federal law 

may expressly preempt state law. See, e.g., Coventry Health Care 

of Mo., Inc. v. Nevils, 137 S. Ct. 1190, 1194 (2017). Second, 

federal law may implicitly preempt a state from legislating in a 

particular “field,” by covering that field so comprehensively as to 

leave no room for state legislation on the same topic. See, e.g., 

Kurns v. Railroad Friction Prods. Corp., 565 U.S. 625, 630-31 

(2012). Third, state law may be preempted when it conflicts with 

federal law, either by placing an actor in a position where 
Gen. 74] 81

compliance with both federal and state law is impossible, see, e.g., 

Mutual Pharm. Co. v. Bartlett, 570 U.S. 472, 479-80 (2013), or by 

posing an “obstacle to the accomplishment and execution of the full 

purposes and objectives” of the federal law, see, e.g., Arizona v. 

United States, 567 U.S. 387, 399-400 (2012) (citation omitted). In 

doubtful cases, federal courts will apply a presumption against 

federal preemption, especially when “the historic police powers of 

the States” are involved. See, e.g., Wyeth v. Levine, 555 U.S. 555, 

565 (2009).

The Federal Act contains an express preemption provision, 

but it is limited in scope. The Act first provides that when a HUD 

manufactured home standard exists in a particular area, conflicting 

or additional state or local standards are displaced:

Whenever a Federal manufactured home 

construction and safety standard established 

under this chapter is in effect, no State or 

political subdivision of a State shall have any 

authority either to establish, or to continue in 

effect, with respect to any manufactured home 

covered, any standard regarding the 

construction or safety applicable to the same 

aspect of performance of such manufactured 

home which is not identical to the Federal 

manufactured home construction and safety 

standard. Federal preemption under this 

subsection shall be broadly and liberally 

construed to ensure that disparate State or 

local requirements or standards do not affect 

the uniformity and comprehensiveness of the 

standards promulgated under this section nor 

the Federal superintendence of the 

manufactured housing industry as established 

by this chapter.

42 U.S.C. § 5403(d) (emphasis added). The statute thus suggests 

that states and localities may enforce standards for manufactured 

home construction and safety as long as they do not address an 

“aspect of performance” that the HUD standards also address. 

Section 5422(a) confirms that suggestion:

Nothing in this chapter shall prevent any State 

agency or court from asserting jurisdiction 

under State law over any manufactured home 

construction or safety issue with respect to 
82 [107 Op. Att’y

which no Federal manufactured home 

construction and safety standard has been 

established pursuant to the provisions of 

section 5403 of this title.

42 U.S.C. § 5422(a). The reference to state agencies alongside 

courts confirms Congress contemplated that not only state common 

law and statutes but also state regulations could apply to 

manufactured homes, provided they address an “issue” that federal 

regulations do not address. See id.

The HUD standards are silent regarding fire sprinklers. It is 

true that the standards do address fire safety generally. 24 C.F.R. 

§§ 3280.201 to 3280.210. But HUD’s fire safety standards 

primarily deal with the flammability of construction materials, see, 

e.g., id. § 3280.203, and smoke alarms, id. § 3280.209. They do 

not address fire suppressing or fire extinguishing systems, let alone 

automatic fire sprinklers specifically. Thus, it appears that a state 

or local sprinkler mandate for manufactured homes would not be 

preempted under § 5403(d) and § 5422(a), because there is no 

federal standard addressing that particular “aspect of performance” 

of manufactured homes.

This conclusion accords with HUD’s consistent, albeit 

informal, view. “When considering whether a federal statute 

preempts state law, we may look to the pronouncements of the 

federal agency that administers the statute for guidance.” 

CallerID4u, Inc. v. MCI Commc’ns Servs. Inc., 880 F.3d 1048, 

1061 (9th Cir. 2018) (citing Wyeth, 555 U.S. at 576-77). Here, 

those pronouncements confirm that state sprinkler requirements are 

not preempted. In 1992, for example, the HUD official in charge 

of the agency’s manufactured housing program advised that a local 

sprinkler mandate in Massachusetts was not preempted, 

presumably because the HUD standards did not address sprinklers. 

Letter from David C. Nimmer, Director, Office of Manufactured 

Housing and Regulatory Functions, U.S. Dep’t of Hous. & Urb. 

Dev., to Jerry C. Connors, President, Manufactured Housing Inst. 

(Jan. 23, 1992) (included in bill file for H.B. 316, 1992 Leg., Reg. 

Sess.). And an informal guidance document currently available on 

HUD’s website states that “HUD has long held that state and local 

sprinkler requirements are . . . not preempted by the general fire 

safety standards.”5

5 U.S. Dep’t of Hous. & Urban Dev., FAQs: Manufactured Housing 

Improvement Act of 2000, https://www.hud.gov/program_offices/
Gen. 74] 83

It might be argued that the phrase “aspect of performance” 

should be read more expansively as referring to a broad category 

of regulation, like fire safety. On that view, because the HUD 

standards address some aspects of fire safety, state and local 

regulation would be foreclosed as to all aspects of fire safety in 

manufactured homes. But HUD has not construed the preemption 

standard so broadly; instead, the agency’s view has been that “for 

there to be Federal preemption, there must be a specific aspect of a 

Federal performance standard which duplicates a local standard.” 

Manufactured Housing Construction and Safety Standards: Notice 

of Internal Guidance on Preemption, 62 Fed. Reg. 3456, 3458 (Jan. 

23, 1997) (emphasis added). 

Case law under a similar preemption provision in the National 

Traffic and Motor Vehicle Safety Act of 1966, on which the HUD 

statute’s preemption language appears to have been based, see Pub. 

L. No. 89-563, 80 Stat. 718, § 103(d), also favors a narrower 

reading. That motor vehicle statute requires that there be a federal 

standard addressing the specific safety feature at issue before state 

and local requirements will be preempted. See Chrysler Corp. v. 

Rhodes, 416 F.2d 319, 325 (1st Cir. 1969), on pet. for reh’g

(interpreting “aspect of performance” as referring to “an item or 

category of equipment”); Chrysler Corp. v. Tofany, 419 F.2d 499, 

506 (2d Cir. 1969) (same); cf. Freightliner Corp. v. Myrick, 514 

U.S. 280, 286-87 (1995) (holding that suspension of one specific 

vehicle safety regulation eliminated express preemption on the 

topic that regulation had addressed). Notably, Rhodes and Tofany

predate the enactment of the federal manufactured home statute in 

1974, suggesting that Congress would have been aware of the 

effect of language similar to the language that had been interpreted 

in those cases. Under that understanding, then, because the HUD 

standards do not address the specific issue of fire sprinklers, the 

Federal Act would not expressly preempt a state or local fire 

sprinkler mandate.

Nor does field preemption apply here. Congress’s inclusion 

of an express preemption provision in a statute ordinarily implies 

that there is no field preemption beyond the express preemption 

provision’s scope, because the text of the preemption provision 

indicates how far Congress wished preemption to extend. See

Myrick, 514 U.S. at 287-89; Sprietsma v. Mercury Marine, 537 

housing/rmra/mhs/faqs72010 (last visited Feb. 25, 2022). The document 

also references a 2010 proposal by HUD to adopt a voluntary sprinkler 

standard that would only apply in jurisdictions that chose to mandate 

sprinklers. See id. However, HUD did not ultimately adopt that 

proposal, for reasons that are not clear. See 24 C.F.R. pt. 3280, subpt. C.
84 [107 Op. Att’y

U.S. 51, 69 (2002). But see National Fed’n of Blind v. United 

Airlines, Inc., 813 F.3d 718, 732-33 (9th Cir. 2016) (holding that 

field preemption could apply beyond express preemption in the 

particular, heavily regulated area at issue, namely air travel). Here, 

that inference is especially strong because Congress in § 5422(a) 

expressly recognized the boundaries of the Federal Act’s 

preemptive scope. See, e.g., Metrophones Telecomms., Inc. v. 

Global Crossing Telecomms., Inc., 423 F.3d 1056, 1072 (9th Cir. 

2005) (recognizing under another statutory scheme that “by 

expressly limiting federal preemption to state requirements that are 

inconsistent with the federal regulations, Congress signaled its 

intent not to occupy the entire field” (emphasis omitted)). Courts 

have thus held that the Federal Act does not preempt the entire field 

of manufactured home construction and safety. See, e.g., In re 

FEMA Trailer Formaldehyde Prods. Liab. Litig., 620 F. Supp. 2d 

755, 762 (E.D. La. 2009) (so holding in the context of a commonlaw tort claim); Harrison v. Skyline Corp., 686 S.E.2d 735, 742 

(W.Va. 2009) (same).

Finally, conflict preemption would not defeat a sprinkler 

mandate. Although the existence of an express preemption 

provision “does not bar the ordinary working of conflict preemption principles,” e.g., Hillman v. Maretta, 569 U.S. 483, 498 

(2013) (citation and emphasis omitted), those ordinary principles 

indicate that there is no preemption here, under either an 

impossibility preemption or an obstacle preemption theory. As an 

initial matter, there is no viable argument that it would be 

impossible for a manufacturer to comply with both federal law and 

a state or local sprinkler mandate, because nothing in the HUD 

standards prohibits the installation of fire sprinklers in 

manufactured homes. Turning to obstacle preemption, we 

recognize that “Federal preemption under [§ 5403(d)] shall be 

broadly and liberally construed” to protect the “uniformity and 

comprehensiveness” of the HUD standards. 42 U.S.C. § 5403(d). 

But § 5422(a)’s express recognition of state authority to regulate 

manufactured home construction and safety in areas not subject to 

federal standards undermines any claim that a state manufactured 

home regulation on a single, limited issue like fire sprinklers could 

be an obstacle to the fulfillment of congressional intent. There is 

no indication of a congressional purpose to preclude a narrowly 

focused state regulation in an area where HUD has been silent (and 

acknowledged its silence). See Wyeth, 555 U.S. at 565 (“[T]he 

purpose of Congress is the ultimate touchstone in every preemption case.”). National uniformity is only one of the purposes 

of the Federal Act; Congress also sought to promote safety and 

prevent personal injuries and property damage in manufactured 
Gen. 74] 85

homes. See 42 U.S.C. § 5401. Indeed, the Federal Act’s 

preemption provisions seem to have been designed to balance 

national uniformity with a continuing regulatory role for the states. 

See id. §§ 5403(d), 5422(a). The presumption against federal 

preemption in areas traditionally subject to state regulation—a 

category that certainly includes building codes—strengthens the 

conclusion that there is no preemption here. See Wyeth, 555 U.S. 

at 565. We thus conclude that the Federal Act leaves state and local 

governments free to mandate fire sprinklers in manufactured 

homes within their jurisdictions.

B. State Law

We next consider whether State law has in fact mandated fire 

sprinklers in manufactured homes in Maryland. In our view, the 

answer is no. Although the Maryland Building Performance 

Standards do require fire sprinklers in those one- and two-family 

homes to which they apply, the General Assembly and the relevant 

regulatory agencies did not intend the Standards to apply to HUDregulated manufactured homes.6

Given the absence of federal preemption, the General 

Assembly could, if it chose, require fire sprinklers in manufactured 

homes. Similarly, the Maryland Department of Labor could likely 

impose such a requirement under the broad authority delegated by 

PS § 12-305(d), which empowers DOL to “adopt regulations that 

relate to issues of construction or safety of manufactured homes for 

which a federal standard has not been established[.]”7 However, 

no current Maryland statute or regulation expressly mandates fire 

sprinklers in manufactured homes specifically. 

6 You did not ask, and so we do not consider, whether State law would 

preempt a local mandate requiring installation of fire sprinklers in 

manufactured homes.

7 We recognize that DOL may not adopt regulations under PS 

§ 12-305(d) in any area “reserved to a local government under [PS] § 12-

303.” PS § 12-305(d). PS § 12-303, in turn, reserves local government 

authority to enact “uniform fire control regulations.” However, we have 

construed the phrase “uniform fire control regulations,” in an opinion 

dealing with modular homes, as preserving exclusive local authority only 

over fire control regulations that do not directly address building design 

and construction, such as subdivision density restrictions and rules for 

placement of fire hydrants. 75 Opinions of the Attorney General 308, 

314 (1990). Section 12-303 thus would not prevent DOL from adopting 

a fire sprinkler mandate for manufactured homes.
86 [107 Op. Att’y

The Maryland Building Performance Standards—the 

statewide building regulations maintained by DOL—do clearly 

require fire sprinklers. Specifically, the MBPS regulations currently 

incorporate the 2018 edition of the International Residential Code. 

COMAR 09.12.51.04. The International Residential Code, in turn, 

requires the installation of fire sprinklers in new one- and twofamily homes. Int’l Residential Code § R313.2 (2018).8

 We thus 

consider whether the MBPS requirements apply to manufactured

homes.

If one were to look just at the language of the MBPS statute 

(and its implementing regulations) in isolation, that language could 

well suggest that their requirements (including the fire sprinkler 

mandate) apply to manufactured homes. Under that statute and 

those regulations, the MBPS requirements apply to “each building 

or structure in the State for which a building permit application is 

received by a local jurisdiction[.]” PS § 12-503(c); accord COMAR 

09.12.51.06A. The definitions of “building” and “structure” are 

taken from the International Building Code, PS § 12-501(b), (i), and 

would seem to include a manufactured home. See Int’l Building 

Code § 202 (2018) (defining a “structure” as “[t]hat which is built 

or constructed” and a “building” as “[a]ny structure utilized or 

intended for supporting or sheltering any occupancy”). Maryland 

law also requires local building permits for manufactured homes, 

and federal law does not exempt manufactured homes from local 

permit requirements. PS § 12-312(b)(6); COMAR 09.12.52.15G(3); 

24 C.F.R. § 3285.901. If we were to read the MBPS statute in 

isolation, then, the MBPS and its fire sprinkler mandate might well 

8

It is not clear whether the IRC, taken by itself, applies to 

manufactured homes. On the one hand, the IRC by its own terms applies 

to the construction of all “detached one- and two-family dwellings and 

townhouses” with limited exceptions not relevant here. Int’l Residential 

Code § R101.2 (2018). The Code, in turn, defines “dwelling” as “[a]ny 

building that contains one or two dwelling units” that are used, intended, 

or designed to be occupied “for living purposes,” id. § R202, and defines 

“dwelling unit” as “[a] single unit providing complete independent living

facilities for one or more persons,” id. These definitions appear broad 

enough to include manufactured homes in the IRC’s scope. On the other 

hand, Appendix E to the IRC specifically addresses “manufactured 

housing used as dwellings,” but does not set any standards for the design 

or construction of the movable portion of the home, deferring instead to 

the HUD standards. See id. App’x E. This could imply that the IRC as 

a whole is not intended to regulate manufactured home design and 

construction. Because we conclude below that the General Assembly 

and DOL did not intend the MBPS regulations to apply to manufactured 

homes, we need not decide whether the IRC standing alone would apply 

to them.
Gen. 74] 87

apply to manufactured homes, as they are “buildings”—structures 

that are intended for occupancy—and local building permits must 

be obtained in order to install them.

We do not interpret statutes in isolation, however. Instead, 

we instead consider the entire statutory scheme, including other 

statutes dealing with the same subject. See, e.g., 100 Opinions of 

the Attorney General 85, 92-93 (2015). Here, that means we must 

consider how a broad reading of PS § 12-503(c) would interact with 

other laws governing manufactured homes. In considering the 

logical result of such a reading, it is important to note that § 12-

503(c) provides for the application of the MBPS as a whole; it does 

not differentiate among particular MBPS provisions. That means 

that, if we were to read PS § 12-503(c) as covering manufactured 

homes, it would follow that the entirety of the MBPS would apply 

to manufactured homes, including the entire International 

Residential Code. Under that reading, manufactured homes would 

be presumptively subject not only to the IRC’s fire sprinkler 

mandate but also to that Code’s provisions governing foundations, 

floors and walls, plumbing, electrical systems, and many other 

areas. See generally Int’l Residential Code (2018). Although the 

Federal Act would preempt any requirement related to an “aspect 

of performance” that the HUD standards also address, the IRC’s 

comprehensive provisions would apply wherever the Federal Act is 

silent. See 42 U.S.C. §§ 5403(d), 5422(a).

We doubt that the General Assembly, in enacting PS § 12-

503(c), intended that result. When the Legislature enacted the 

MBPS statute, including § 12-503(c), in 1993, it was aware that a 

detailed and complex construction and safety code—the HUD 

standards—already existed for manufactured homes. See, e.g., 

Junek v. St. Mary’s County Dep’t of Soc. Servs., 464 Md. 350, 363 

(2019) (explaining that the General Assembly is presumed to act 

with knowledge of existing law). In fact, the General Assembly 

itself had also already enacted separate legislation governing 

manufactured homes years earlier, acknowledging the federal 

requirements and delegating specific authority to the thenDepartment of Economic and Community Development to 

supplement the federal requirements by regulation, to the extent 

necessary and permitted by federal preemption. 1976 Md. Laws, 

ch. 422 (enacting Art. 41, § 266EE-7, now codified as amended at 

PS §§ 12-305(d) and 12-312). A statewide code also already 
88 [107 Op. Att’y

existed for modular homes. See 1971 Md. Laws, ch. 662 (enacting 

Art. 41, § 266EE-3, now codified as amended at PS § 12-305). 

The primary purpose behind the MBPS was instead to 

establish a statewide building code for site-built buildings, which 

were, at the time, governed by a patchwork of inconsistent local 

building codes (and, in some jurisdictions, no building code at all). 

See 1993 Md. Laws, ch. 200 (Preamble) (explaining that the 

purpose of the MBPS was to replace the “nine different codes” for 

site-built buildings enacted by “19 counties and 59 municipalities 

in Maryland”); MBPS Report, supra, at 3 (same). Because 

manufactured homes already had a statewide—indeed, a 

nationwide—code (the HUD standards), we infer that the General 

Assembly did not expect that the MBPS, a different but largely 

overlapping statewide code, would apply to manufactured homes. 

Although perhaps DOL could apply the MBPS to manufactured 

homes under its regulatory authority (except to the extent 

preempted by federal law), see PS § 12-305(d), we do not believe 

that the General Assembly intended PS § 12-503(c), which does 

not expressly address manufactured homes at all, to have that 

effect.

Indeed, in line with that understanding, the General Assembly 

has consistently maintained separate statutory and regulatory 

schemes for site-built buildings, modular homes, and manufactured 

homes. In 1971, when the General Assembly enacted the first State 

statute governing manufactured homes and industrialized buildings 

(before there was any federal law on the subject), the Legislature 

mandated that the then-Department of Economic and Community 

Development (“DECD”) adapt one of the national model building 

codes for industrialized buildings but that it develop a separate set 

of standards for manufactured homes. See 1971 Md. Laws, ch. 662 

(enacting Art. 41, § 266EE-3). That distinction suggests a 

legislative intent that manufactured homes should be subject to 

separate rules developed specifically for them, as opposed to rules 

primarily developed for other types of homes. The agency 

complied and developed a separate set of regulations for 

manufactured homes based on a different model code. See

Memorandum from Dep’t of Econ. & Cmty. Dev. to House Econ. 

Matters Comm. on H.B. 724 (1976); 1971 Md. Laws, ch. 662 

(enacting Art. 41, § 266EE-3). Another statute passed at the same 

session in 1971 directed the agency to develop yet a third code: a 

voluntary Model Performance Code for site-built buildings. 1971 

Md. Laws, ch. 663 (enacting Art. 41, § 257-J, now codified as 

amended at PS § 12-201). This code was to be consistent with the 

rules for industrialized buildings but only “to the extent practicable.” 
Gen. 74] 89

Id. Thus, the Legislature contemplated, and the appropriate agency 

created, distinct regulatory codes for each of the three building 

categories.

In 1976, following enactment of the federal manufactured 

home statute, Pub. L. No. 93-383, tit. VI, 88 Stat. 633, 700 (1974), 

the General Assembly deleted the State statute’s substantive 

provisions for manufactured homes, and substituted provisions 

authorizing the State to administer the Federal Act as HUD’s 

delegate. 1976 Md. Laws, ch. 422. This was a further marker of 

legislative intent that manufactured homes be subject to a separate 

regulatory scheme—now primarily federal, with the possibility of 

limited State-law supplementation. See PS §§ 12-305(d), 12-312. 

When the General Assembly enacted the MBPS statute in 1993, 

nothing in its text or legislative history suggested an intent to 

change this established system and subject site-built homes and 

manufactured homes to the same code for the first time, especially 

given that manufactured homes were already subject to the HUD 

standards. Modular homes, too, remained subject to their own 

regulatory scheme, based on but distinct from the MBPS. See PS 

§ 12-305; COMAR 09.12.52.07. To be sure, in 2012, the General 

Assembly enacted a statute prohibiting local governments from 

weakening the MBPS fire sprinkler requirements for those one- and 

two-family homes that were subject to the MBPS. 2012 Md. Laws, 

chs. 265, 266 (enacting PS § 12-504(a)(1)(iii)). But that enactment 

did not purport to extend the MBPS—i.e., to apply the fire sprinkler 

mandate to manufactured homes for the first time—only to protect 

the MBPS provisions’ existing application from local interference. 

The State Fire Marshal, testifying in support of the 2012 

legislation, did state that he believed, as a matter of policy, that a 

fire-sprinkler mandate should apply to all types of homes including 

manufactured homes. See Hearing on S.B. 602 Before the Senate 

Educ., Health & Env’tl Affairs Comm., 2012 Leg., Reg. Sess. (Mar. 

6, 2012) (statement of the State Fire Marshal); Hearing on H.B. 

366 Before the House Env’tl Matters Comm., 2012 Leg., Reg. Sess. 

(Feb. 16, 2012) (statement of the State Fire Marshal). But there is 

no indication that he thought § 12-504(a)(1)(iii) would have that 

effect or, even if he did, that the General Assembly agreed. 

Our prior opinion on a similar issue also supports the 

conclusion that the General Assembly did not intend to apply the 

MBPS to manufactured homes by implication in PS § 12-503(c). 

Shortly after the General Assembly first enacted legislation 

governing “industrialized buildings” (a category that includes 

modular homes but not manufactured homes), we opined that the 

State Plumbing Regulations issued by the then-Department of 
90 [107 Op. Att’y

Licensing and Regulation did not apply to industrialized buildings, 

and that only the construction code adopted by DECD specifically 

for industrialized buildings governed plumbing requirements for 

those buildings. 58 Opinions of the Attorney General 240, 245 

(1973). We reasoned there that the General Assembly did not 

intend industrialized buildings to be subject to two sets of partially 

overlapping State-enacted plumbing regulations. See id. at 242-44. 

The same rationale should apply here: because the General 

Assembly in 1993 understood that manufactured homes were 

already subject to their own pre-existing statutory and regulatory 

building code, mostly flowing from the HUD standards, it is 

unlikely that there was an intent to also subject them to a second, 

overlapping building code, the MBPS.

An interpretation that would purport to impose the entire 

MBPS on manufactured homes could also raise obstacle 

preemption concerns under the Federal Act, even if its application 

were limited to areas where the Federal Act is silent. While 

Congress clearly contemplated that a state or local government 

could impose individual, specific requirements on manufactured 

homes, see 42 U.S.C. § 5422(a), there would at least be a question 

as to whether Congress expected a state to be able to impose a 

complete, largely overlapping building code, designed for site-built 

homes, onto HUD-regulated manufactured homes as well. See

Scurlock v. City of Lynn Haven, 858 F.2d 1521, 1525 (11th Cir. 

1988) (holding that city could not use zoning ordinance to require 

manufactured homes to comply with a standardized building code 

other than the HUD standards); Colorado Mfr’d Hous. Ass’n v. 

Board of County Comm’rs, 946 F. Supp. 1539, 1552-53 (D. Colo. 

1996) (same). That approach by a state would work a much greater 

interference with the administration and national uniformity of the 

HUD standards than would a standalone fire sprinkler requirement. 

See 42 U.S.C. §§ 5401, 5403(d). Although we do not resolve that 

preemption question here, these potential preemption concerns lead 

us to favor a reading of PS § 12-503(c) that does not purport to 

apply the full set of MBPS provisions to manufactured homes, 

especially in the absence of any clear legislative intent to do so. 

See, e.g., Bank of Am. v. Stine, 379 Md. 76, 90 (2003) (State statutes 

should be construed to avoid federal preemption concerns where 

possible).

DOL’s regulations for manufactured and modular buildings 

also align with this conclusion. Those regulations are found in a 

separate chapter from the MBPS regulations, see COMAR 

09.12.52, a further indication that non-site-built homes are not 

subject to the MBPS. The scope provision in these regulations 
Gen. 74] 91

explains that the HUD standards generally supersede the State’s 

regulation of manufactured homes and notes only one express 

exception where the agency’s regulations do in fact cover 

manufactured homes, namely, COMAR 09.12.52.15. See COMAR 

09.12.52.01B. COMAR 09.12.52.15, in turn, imposes only limited 

requirements on manufactured homes, relating to auxiliary issues 

such as manufactured home installation and local code enforcement, 

declaring that the Federal Act otherwise gives HUD “complete 

jurisdiction over the design and construction of manufactured 

homes” and “supersedes all state laws on this subject.” And 

nowhere in these regulations governing manufactured homes is 

there any suggestion that the provisions in the separate MBPS 

regulations apply. These regulations thus signify a regulatory 

intent that manufactured home construction and safety be governed 

by federal law.

Finally, the relevant State agencies’ interpretation of the 

governing statutes and regulations as not requiring fire sprinklers 

in manufactured homes should resolve any remaining doubts. An 

agency’s interpretation of the statute it administers is ordinarily 

entitled to deference, as is an agency’s interpretation of its own 

regulations. See, e.g., Kor-Ko Ltd. v. Maryland Dep’t of Env’t, 451 

Md. 401, 412 (2017). DHCD had, until recently, authority to 

regulate manufactured home construction and safety, see PS § 12-

305(d), and the State Fire Marshal has authority to enforce the 

State’s fire sprinkler mandate, see PS § 6-305(a)(3). Both of these 

agencies have opined that State law does not require fire sprinklers in 

manufactured homes. See Wang Memorandum, supra; Fire Marshal 

Memorandum, supra. Specifically, both have taken the view that the 

only State regulation applicable to manufactured home construction 

and safety is COMAR 09.12.52.15, which does not contain a 

sprinkler mandate. See Wang Memorandum, supra, at 1; Fire 

Marshal Memorandum, supra, at 1. Nor has DOL adopted a 

different position since inheriting DHCD’s former authority over 

manufactured homes. Deference to the agencies’ expertise further 

bolsters the conclusion that manufactured homes are not subject to 

the sprinkler mandate.

III

Conclusion

In sum, federal law would not preempt a State requirement 

that manufactured homes be equipped with fire sprinklers. But 

although the Maryland Building Performance Standards, 

incorporating the International Residential Code, do require fire 

sprinklers in “site-built” one- and two-family homes (and separate 
92 [107 Op. Att’y

regulations require fire sprinklers in one- and two-family modular 

homes), the General Assembly did not intend the Maryland 

Building Performance Standards to apply to manufactured homes, 

which have been subject to their own regulatory regime—the HUD 

standards—since long before the General Assembly established the 

MBPS. Thus, State law does not currently require fire sprinklers 

in manufactured homes.

Brian E. Frosh

Attorney General of Maryland

Thomas S. Chapman

Assistant Attorney General

Patrick B. Hughes

Chief Counsel, Opinions and Advice