Date: Jun 8, 2026

Iowa Tax Statutes Construed by Ordinary Meaning; Unattached Commercial Storage Tanks Are Nontaxable “Equipment” Under Iowa Code § 427A.1(1)(d)

1. Introduction

In Chickasaw County Board of Review v. Property Assessment Appeal Board; and Growmark, Inc. (Iowa June 5, 2026), the Iowa Supreme Court addressed whether eleven 90,000-gallon above-ground propane tanks at Growmark, Inc.’s New Hampton fuel terminal were taxable as “real property” or excluded from taxation as “personal property” under Iowa Code chapter 427A.

The Chickasaw County assessor included nearly $2 million in tank value in the real-property assessment. The Chickasaw County Board of Review affirmed, classifying the tanks as taxable “improvements” under Iowa Code § 427A.1(1)(c). Growmark appealed to the Property Assessment Appeal Board (PAAB), which reversed and held the tanks were unattached “equipment” under § 427A.1(1)(d) and therefore not taxable. The district court affirmed PAAB. The Board of Review appealed to the Iowa Supreme Court.

The case raised three recurring issues in Iowa property-tax litigation: (1) the line between “improvements” and “equipment” under § 427A.1(1), especially for industrial items resting on foundations; (2) the role of “removability” in classification; and (3) how much weight courts should give to Department of Revenue (DOR) manuals and guidance. In addition, the court used this case to announce a broader interpretive shift: tax statutes will be construed using ordinary statutory-interpretation principles, not special tax-specific pro-taxpayer or pro-government presumptions.

2. Summary of the Opinion

Holding on classification: Growmark’s propane tanks are “equipment” under Iowa Code § 427A.1(1)(d), not “improvements” under § 427A.1(1)(c). Because the tanks are undisputedly unattached to the concrete saddles (foundations), they are not assessable as real property and are nontaxable personal property under § 427A.2.
StateLine limited: StateLine Cooperative v. Iowa Property Assessment Appeal Board, 958 N.W.2d 807 (Iowa 2021), concerned whether property qualified as manufacturing “machinery” under § 427A.1(1)(e) (and thus exempt via § 427B.17), and does not create a general “storage vs. processing” test for distinguishing improvements from equipment under § 427A.1(1)(c) and (d).
Agency deference: PAAB has no interpretive authority over § 427A.1; its statutory interpretations are reviewed for errors of law. Although DOR has interpretive authority in this area, internal DOR manuals/guides/memos cited here were not owed § 17A.19(11)(c) deference because they did not squarely address the controlling legal issue and were outdated/incomplete.
New interpretive rule: Going forward, Iowa courts will construe tax statutes “according to their ordinary meaning” using the same principles applicable to other statutes, overruling prior cases that required liberal construction for taxpayers (as to imposition) and strict construction against taxpayers (as to exemptions) to the extent they said otherwise.

3. Analysis

3.1. Precedents Cited

A. Standards of review and interpretive authority

StateLine Cooperative v. Iowa Property Assessment Appeal Board, 958 N.W.2d 807 (Iowa 2021): The court relied on StateLine Cooperative for the framework that PAAB lacks express interpretive authority over § 427A.1, so courts review PAAB’s statutory interpretation for “errors of law” under Iowa Code § 17A.19(10)(c). StateLine Cooperative also supplied the distinction between deference to PAAB versus deference to DOR.
Naumann v. Iowa Prop. Assessment Appeal Bd., 791 N.W.2d 258 (Iowa 2010) and Renda v. Iowa C.R. Comm'n, 784 N.W.2d 8 (Iowa 2010): These cases were used to restate chapter 17A judicial-review principles: relief is available only if substantial rights are prejudiced and a statutory ground in § 17A.19(10) is met, and the level of review depends on whether interpretive authority is vested in the agency.
Wendling Quarries, Inc. v. Prop. Assessment Appeal Bd., 865 N.W.2d 635 (Iowa Ct. App. 2015): Cited for the proposition that, although PAAB’s legal interpretations are reviewed for errors at law, PAAB’s factual findings bind if supported by “substantial evidence.” It also becomes a key substantive comparator for distinguishing “equipment” from “improvements.”

B. Deference to DOR guidance versus rules/contested cases

Story Cnty. Wind, LLC v. Story Cnty. Bd. of Rev., 990 N.W.2d 282 (Iowa 2023): Confirmed DOR has “some interpretive authority” with respect to § 427A.1, reinforcing that deference questions are nuanced and context dependent.
Iowa Med. Soc'y v. Iowa Bd. of Nursing, 831 N.W.2d 826 (Iowa 2013); Iowa Ag Constr. Co. v. Iowa State Bd. of Tax Rev., 723 N.W.2d 167 (Iowa 2006); Auen v. Alcoholic Beverages Div. of the Iowa Dep't of Com., 679 N.W.2d 586 (Iowa 2004): These decisions illustrate when Iowa courts defer to agency interpretations embedded in duly promulgated administrative rules.
AFSCME Iowa Council 61 v. Iowa Pub. Emp. Rels. Bd., 846 N.W.2d 873 (Iowa 2014); Sherwin-Williams Co. v. Iowa Dep't of Revenue, 789 N.W.2d 417 (Iowa 2010): Cited for the proposition that deference can also apply to agency interpretations rendered in contested cases where the agency is the decisionmaker. The court distinguished that scenario from this case, where PAAB—not DOR—made the taxable/non-taxable determination.
Anderson v. Iowa Dep't of Hum. Servs., 368 N.W.2d 104 (Iowa 1985): The court used Anderson to caution against reliance on agency manuals not adopted as rules or properly indexed written policy statements, supporting the refusal to give strong deference to informal guidance.
Nance v. Iowa Dep't of Revenue, 908 N.W.2d 261 (Iowa 2018) (Mansfield, J., dissenting) and City of Marion v. Iowa Dep't of Rev. & Fin., 643 N.W.2d 205 (Iowa 2002): Invoked to underscore that even where deference is sometimes appropriate, outdated or incomplete interpretations that fail to grapple with intervening legal changes may not merit weight.

C. Tax-statute construction (the opinion’s most sweeping doctrinal move)

Iowa Auto Dealers Ass'n v. Iowa Dep't of Revenue, 301 N.W.2d 760 (Iowa 1981); Lowe's Home Ctrs., LLC v. Iowa Dep't of Revenue, 921 N.W.2d 38 (Iowa 2018): Representative of Iowa’s older tax-specific canons: tax imposition construed in favor of taxpayers; exemptions construed against taxpayers. The court rejected continuing reliance on these canons as extra-textual and potentially conflicting.
StateLine Cooperative, 958 N.W.2d 807; The court echoed StateLine Cooperative’s skepticism of judicially created canons not grounded in enacted text (citing Scalia & Garner).
S. Iowa Methodist Homes, Inc. v. Bd. of Rev. of Cass Cnty., 136 N.W.2d 488 (Iowa 1965): Used to highlight tension between tax canons and Iowa Code § 4.2 (liberal construction of the Code).
Van Buren Cnty. Hosp. & Clinics v. Bd. of Rev., 650 N.W.2d 580 (Iowa 2002) and Stingray Pressure Pumping, L.L.C. v. Harris, 222 N.E.3d 597 (Ohio 2023): Cited to show prior justifications for strict exemption construction were policy-based, and that other courts have recognized similar conflicts with plain-meaning commitments.
Cianzio v. Iowa State Univ., 14 N.W.3d 716 (Iowa 2024) (quoting Doe v. State, 943 N.W.2d 608 (Iowa 2020)) and Christensen v. Iowa Dep't of Revenue, 944 N.W.2d 895 (Iowa 2020): Served as authority for the court’s “ordinary and fair meaning” approach and as examples of now-overruled tax-canon language (to the extent inconsistent).

D. Substance: defining “equipment” vs. “improvement,” and the role of removability

Rose Acre Farms, Inc. v. Bd. of Rev., 479 N.W.2d 260 (Iowa 1991): A foundational case for distinguishing “equipment” from “improvements” under § 427A.1(1), and for using removability/economic reality to assess whether items are the kind ordinarily removed under § 427A.1(3).
Western Outdoor Advertising Co. v. Board of Review, 364 N.W.2d 256 (Iowa 1985): Explained that the “ordinarily removed” clause in § 427A.1(3) does not matter for § 427A.1(1)(c) items because attachment is not required there. The court used it to evaluate and ultimately discount the relevance of a 1985 DOR memo and 1986 technical bulletin.
Cowles Commc'ns Inc. v. Bd. of Rev., 266 N.W.2d 626 (Iowa 1978), superseded by statute, 1977 Iowa Acts ch. 43, § 14, as recognized in W. Outdoor Advert. Co., 364 N.W.2d at 257-58: Provided the earlier “ordinarily removed” analysis that later became statutory in § 427A.1(3) and informed the factors discussed in Rose Acre Farms.
McDermott Propane, LLC v. Board of Review, No. 20-1619, 2022 WL 468702 (Iowa Ct. App. Feb. 16, 2022) (unpublished): While not binding precedent, the court treated it as persuasive and aligned its reasoning with it: propane storage tanks supported by piers were “equipment,” not “improvements.”
Griffin Pipe Prods. Co. v. Bd. of Rev., 789 N.W.2d 769 (Iowa 2010): Used to situate § 427A.1(1)(d) as a broad category including non-manufacturing equipment, while § 427A.1(1)(e) is narrower and manufacturing-specific (with exemption via § 427B.17).
Young v. Iowa Dep't of Transp., 490 N.W.2d 554 (Iowa 1992): Referenced for the common-law “fixture” approach in other contexts, reinforcing that permanence/annexation and intent matter when characterizing property as part of the realty.
Beverage v. Alcoa, Inc., 975 N.W.2d 670 (Iowa 2022) (quoting Com. Bank v. McGowen, 956 N.W.2d 128 (Iowa 2021)) and State v. Wade, 7 N.W.3d 511 (Iowa 2024): Provided general interpretive principles: ordinary meaning, context, and harmonization with related provisions.
R.C. Maxwell Co. v. Galloway Township, 679 A.2d 141 (N.J. 1996): Cited as persuasive authority for construing “improvement” as something “obviously…inherently permanent,” supporting the court’s ordinary-meaning approach.

3.2. Legal Reasoning

A. The statutory architecture: why the label (“improvement” vs. “equipment”) controls taxability

Iowa Code chapter 427A creates a high-stakes binary: items are taxable only if they fall within § 427A.1’s definition of “[p]roperty taxed as real property.” Everything else is nontaxable “personal property” under § 427A.2. Because Iowa repealed taxes on personal property effective July 1, 1987, classification disputes under § 427A.1 determine whether property value is taxed at all.

The core interpretive problem is that § 427A.1(1) uses overlapping categories:

§ 427A.1(1)(c): “Buildings, structures, or improvements” taxed as real property if constructed on/in land, attached to land, or “placed upon a foundation whether or not attached to the foundation.”
§ 427A.1(1)(d): “Buildings, structures, equipment, machinery, or improvements” taxed as real property only if “attached” to paragraph (c) items.

This structure makes the classification question dispositive. If the propane tanks are “improvements” under (c), they are taxable even if not attached to the foundation. If they are “equipment” under (d), they are taxable only if “attached”—and here, attachment was undisputedly absent.

B. Rejecting a “storage vs. processing” test for (c) vs. (d)

The Board of Review argued that storage tanks should be treated like warehouses (and therefore like improvements/buildings), and relied on StateLine Cooperative to claim a functional test: storage items are taxable; processing items are not. The court rejected that as a category error.

In StateLine Cooperative, the “storage vs. processing” distinction mattered only to determine whether property was “Machinery used in manufacturing establishments” under § 427A.1(1)(e)—a status that triggers exemption through § 427B.17. That framework does not control the separate question whether non-manufacturing items are “improvements” under (c) or “equipment” under (d). The court emphasized that § 427A.1(1)(d) can include equipment used in commercial (non-manufacturing) operations, consistent with Griffin Pipe Prods. Co..

C. Ordinary meaning of “equipment” and “improvement,” informed by Iowa cases

Because chapter 427A does not define “equipment” or “improvement,” the court started with ordinary meaning (including Black’s Law Dictionary), then checked that meaning against Iowa precedent:

Improvements are additions that increase land’s utility and are relatively permanent—akin to fixtures.
Equipment is an implement used for a specific business purpose; typically removable without damaging the land or the supporting structure.

Rose Acre Farms, Inc. v. Bd. of Rev. provided the court’s most direct prior guidance: items integral to a business operation (cages, systems, bins) were “more clearly ‘equipment.’” Wendling Quarries, Inc. v. Prop. Assessment Appeal Bd. then sharpened the taxonomy by splitting a system into taxable foundational components (concrete base and approaches) and nontaxable removable components (the scale), focusing on permanence and removability.

D. Removability matters even when “attachment” is conceded absent

The Board of Review sought to minimize removability, arguing § 427A.1(3) only matters when something is attached. The court clarified removability plays two roles:

Under § 427A.1(3), even something that is “attached” under § 427A.1(2) is treated as “not attached” if it is the kind ordinarily removed when the owner moves.
More broadly (under § 427A.1(1)’s classification inquiry), removability is a factor that “sheds light” on whether an item is equipment rather than an improvement.

Thus, even with no dispute the tanks were unattached, their movability and the economic logic of moving them (versus replacing them) helped demonstrate they function as equipment, not a permanent accession to the land.

E. Application to Growmark’s tanks

The controlling facts were simple: the tanks sit on concrete saddles but are held by gravity alone, not fastened; they can be moved; removal would not damage the saddles or land; moving each tank (~$28,124) is far cheaper than replacement (≥$180,000); and the PAAB credited testimony that Growmark would take the tanks if it relocated.

On those facts, the court concluded the tanks are “implements used for a specific purpose within Growmark’s fuel distribution operations”—i.e., “equipment” under § 427A.1(1)(d). Because they are not “attached,” they cannot be assessed as real property and are nontaxable under § 427A.2.

F. DOR materials: considered but not deferred to

The Board of Review offered DOR materials (the Iowa Real Property Appraisal Manual; 1977 and 1984 valuation guides; a 1985 memo; a 1986 technical bulletin) treating tanks as real property. The court acknowledged DOR’s interpretive authority in this statutory neighborhood (per StateLine Cooperative), but refused to give these materials § 17A.19(11)(c)-type deference here because:

they were not promulgated administrative rules;
they did not address the key threshold question—classification under § 427A.1(1)(c) vs. § 427A.1(1)(d);
some content was outdated or misaligned with later legislative changes (including the post-2002 manufacturing-machinery exemption landscape); and
the 1985 memo/1986 bulletin were keyed to Western Outdoor Advertising Co. v. Board of Review’s attachment/removability issues in the (c) context, not the (c) vs. (d) classification problem.

3.3. Impact

A. Immediate property-tax consequences for industrial and commercial sites

The decision strengthens taxpayers’ ability to exclude large, valuable industrial items from assessments when the items are functionally business implements (equipment) and are not permanently affixed, even if they rest on purpose-built foundations. For fuel terminals and similar operations, the court’s analysis aligns with McDermott Propane, LLC v. Board of Review and likely accelerates statewide reassessment practices beyond 30,000-gallon tanks.

B. A clearer doctrinal boundary: “foundation taxed; removable implement not taxed”

The opinion implicitly endorses the analytical move seen in Wendling Quarries, Inc. v. Prop. Assessment Appeal Bd.: treat the foundation (concrete saddles/piers) as taxable structures/improvements, while treating the business implement placed upon it as equipment—unless attached. This encourages assessors and reviewing bodies to disaggregate integrated systems into taxable realty components and nontaxable personal-property components.

C. Constraining “warehouse analogy” arguments

Counties often argue that containers or storage mechanisms “are really warehouses.” The court’s reasoning signals that such functional analogies are not enough: unless the item is properly a “building, structure, or improvement” in ordinary meaning (permanence, accession to land), it will not be taxed under § 427A.1(1)(c) merely because it stores something.

D. Agency guidance: less leverage for informal manuals in litigation

Although assessors must use the state appraisal manual for valuation, this case differentiates valuation tools from legal-classification authority. Counties relying on informal guidance may face more skepticism unless DOR addresses the issue through rulemaking or formal, current interpretations that track modern statutory structure.

E. The most far-reaching effect: Iowa abandons special tax canons

The court’s prospective instruction—construe tax statutes like any other statute—may reshape Iowa tax litigation beyond property tax: litigants can expect less reliance on generalized pro-taxpayer/pro-government presumptions and more emphasis on enacted text, context, and ordinary meaning. The opinion expressly overrules prior cases “to the extent they say otherwise,” including Christensen v. Iowa Dep't of Revenue, Lowe's Home Ctrs., LLC v. Iowa Dep't of Revenue, Sherwin-Williams Co. v. Iowa Dep't of Revenue, and Iowa Auto Dealers Ass'n v. Iowa Dep't of Revenue.

4. Complex Concepts Simplified

A. “Improvement” vs. “equipment” (why the label matters)

Under § 427A.1(1)(c), an “improvement” placed on a foundation is taxable even if it is not attached. Under § 427A.1(1)(d), “equipment” is taxable only if attached to a (c) item. So calling the same object an “improvement” can make it taxable, while calling it “equipment” can make it nontaxable if unattached.

B. “Attached” and “ordinarily removed”

Section 427A.1(2) defines “attached” (adhesive, fasteners, or removal requiring substantial alteration). Section 427A.1(3) adds an exception: even if something is “attached,” it is treated as “not attached” if it is the kind of property ordinarily removed when the owner moves. In this case, the tanks were already unattached, but their movability still supported the broader classification as “equipment.”

C. “Deference” to agencies

Courts sometimes defer to agencies when the legislature gives the agency authority to interpret a statute. Here, PAAB lacked that authority for § 427A.1, so the court independently interpreted the statute. DOR has interpretive authority in this area, but the court declined to defer to informal, outdated, or non-targeted guidance.

D. “Substantial evidence” vs. “errors of law”

“Substantial evidence” review applies to an agency’s fact findings (e.g., whether a tank is fastened or movable). “Errors of law” review applies to legal questions (e.g., what “equipment” means in § 427A.1(1)(d)). The court accepted PAAB’s supported facts but decided the legal meaning itself.

5. Conclusion

The Iowa Supreme Court affirmed that Growmark’s unattached propane tanks are nontaxable “equipment” under Iowa Code § 427A.1(1)(d), not taxable “improvements” under § 427A.1(1)(c), reinforcing a permanence-and-removability-centered distinction between land improvements and business implements. The decision limits attempts to treat storage containers as taxable realty based on warehouse analogies or a generalized “storage vs. processing” test derived from StateLine Cooperative.

Beyond property classification, the opinion’s largest doctrinal move is interpretive: Iowa tax statutes will now be construed by ordinary meaning using standard tools of statutory construction, not special tax-specific presumptions. That shift, coupled with the court’s skepticism toward informal agency guidance, is likely to influence future tax disputes well beyond propane tanks.