. Because we reverse the trial court, we need not address the fraternity’s additional arguments raised in the petition for certiorari.

. The 1924 original zoning ordinance does not appear in the record. However, in a memorandum from the City’s planning division to the Cily Manager, the City describes the zoning history prior to 1954 and it provides in pertinent part:

"... Norman had an adopted zoning ordinance in 1924, which was much simpler than today's version. Ordinance #401 listed five use districts, the lowest being the U-l Residence district. That district governed this tract. Section III of that code allowed, by right, 'religious and fraternal dormitories, college fraternities and sororities, and private clubs, except a club the chief activity of which is service customarily carried on as a business.' When this structure was first built, the fraternity/sorority use was legal and conforming. ...” (Emphasis in original.)

The fraternity does not dispute the City’s description of the original ordinance.

. The 1954 City of Norman Zoning Ordinance No. 884, Article II, § 1 provides in pertinent part:

"R-l Single-Family Dwelling District:

1.1 Uses Permitted:

Property and building in a R-l, single-family dwelling district, shall be used only for the following purposes:

(a) Detached one-family dwelling.

(b) Church.

(c) School offering general educational courses the same as ordinarily given in public schools and having no rooms regularly used for housing and sleeping.

(d) Library....”

. Title 11 O.S.2001 § 44-107.1(A) provides:

"The lawful nonconforming use of a building, structure or premises as such existed at the time of the adoption and recording of any ordinance affecting it, may be continued, although such use does not conform with the provisions of such ordinance. The municipality may provide for the termination of lawful nonconforming uses either by specifying the period or periods within which such use shall be required to cease, or by designating conditions or circumstances which shall cause such use to cease, or by providing a formula or formulas whereby the compulsory termination of a nonconforming use shall be so fixed as to allow a reasonable period for the amortization . of the investment in the nonconformance.”

The 1954 City of Norman Zoning Ordinance No. 884, Article V, § 30 defined non-conforming use as:

"Any lawful use of land, building or structure, existing at the time of adoption of the Zoning Map, which does not conform with the regulations of the district in which it is situated.”

Article I, § 9 provides in pertinent part:

"Non-Conforming Uses:

Any use or structure existing at the time of enactment or subsequent amendment of this Ordinance, but not in conformity with its provisions, may be continued with the following limitations. Any use or building which does not conform to the provisions of this Ordinance may not be:

(a)Changed to another non-conforming use;

. The 1954 City of Norman Zoning Ordinance No. 884, Article II, § 2 provides in pertinent part:

"R-2, Two-family Dwelling District:

2.1 Property and buildings in a R-2, two-family dwelling district, shall be used only for the following purposes:

(a) Any uses permitted in R-l, single-family dwelling district.

(b) Two-family dwelling, or a single-family dwelling and a garage apartment.

(c) Boarding house, rooming house....”

. The 1954 City of Norman Zoning Ordinance No. 884, Article V, § 7 defined boarding house as:

"A building other than a hotel where, for compensation and by prearrangement for definite periods, meals, or lodging, and meals, are provided for (5) or more persons.”

. The minutes of the October 8, 1958 City Planning Commission meeting provide in pertinent part:

*4"... Mi'. Luttrell explained that he and the City Manager had studied the situation very carefully and had given an administrative opinion that the proposed new use would not be the same as the present use. This was the reason that the petition sought to have the property rezoned. ”

.The 1954 City of Norman Zoning Ordinance No. 884, Article II, § 1 provides in pertinent part:

“R-l Single-Family Dwelling District:

1.2 Uses Permissible on Review:

The following uses may be permissible on review by the City Planning Commission in accordance with provisions contained in Article III, section 6, provided that structures incidental to these uses are located twenty-five (25) feet from any property line:

(a) Municipal use, public building and public utility.

(b) Private club not conducted for profit."

The minutes of the October 8, 1958 City Planning Commission meeting provide in pertinent part:

"... In a general discussion it was determined that the proposed boarding home for elderly women would have these characteristics:

1. It is a nonprofit organization

2. No sick or infirm person would be allowed membership or residence in the club or building.

3. The property is not to be used as a rest home

4. Meals will be furnished

5. The nature of the club would be of such high character that there would be no adverse effect upon neighboring property.”

. The Code of the City of Norman, Zoning Ordinance § 22-419 NON-CONFORMING USES provides:

"1. Continuation. Any use or structure existing at the time of enactment or subsequent amendment of this Ordinance, but not in conformity with its provisions, may be continued with the following limitations. Any use or building which does not conform to the provisions of this Ordinance may not be:

(a) Changed to another non-conforming use.

(b) Re-established after discontinuance for two years.

(c) Extended except in conformity to this Ordinance.

Provided, however, that all buildings and uses existing at the time of passage of this Ordinance which do not comply with the required off-street parking requirements, as specified in Article XII, Sec. 431.5-431.9, shall not be defined as non-conforming uses because of lack of said off-street parking facilities under the terms of this Ordinance. (Ord.884, Art. 1, Sect.9).”

. Title 11 O.S.2001 § 44-110(D) provides in pertinent part:

"A. An appeal from any action, decision, ruling, judgment or order of the board of adjustment may be taken ... to the district court in the county in which the municipality is located. D. The appeal shall be heard and tried de novo in the district court....”

. The Code of the City of Norman, Zoning Ordinance § 22-419, see note 9, supra; City of Sugar Creek v. Reese, 969 S.W.2d 888, 891 (Mo.App. 1998)[Nonconforming use means use of land that lawfully existed prior to the enactment of a zoning ordinance and which is maintained after the effective date of the ordinance even though not in compliance with use restrictions.]; State ex rel. Brooks v. Hartland Sportsman’s Club, Inc., 192 Wis.2d 606, 531 N.W.2d 445, 448 (1995)[A legal nonconforming use is a use of land for purposes not permitted under the zoning ordinance, but which was an active and actual use existing prior to the commencement of the zoning ordinance.].

. The Code of the City of Norman, Zoning Ordinance § 22-419, see note 9, supra.

. Bankoff v. Board of Adjustment of Wagoner County, 1994 OK 58, ¶17, 875 P.2d 1138 [Review of denial of conditional use permit for landfill.]; Vinson v. Medley, 1987 OK 41, ¶ 10, 737 P.2d 932 [Denial of zoning variance.]; Walkingstick v. Board of Adjustment of City of Tulsa, 1985 OK 70, ¶ 29, 706 P.2d 899 [Zoning ordinance variance to permit drilling.]; Banks v. City of Bethany, 1975 .OK 128, ¶ 6, 541 P.2d 178 [Denial of variance from zoning ordinance.]; Bailey v. Uhls, 1972 OK 147, ¶ 13, 503 P.2d 877 [Denial of variance to erect sign.]; Brown v. Fraser, 1970 OK 50, ¶ 19, 467 P.2d 464 [Denial of variance to construct residence.]; Board of Adjustment of Oklahoma City v. Shanbour, 1967 OK 189, ¶ 15, 435 P.2d 569 [Denial of special permit.]; Thompson v. Phillips Petroleum Co., 1944 OK 168, ¶ 6, 147 P.2d 451 [Denial of permit to drill well.]; Application of Shadid, 1951 OK 359, ¶ 16, 238 P.2d 794 [Denial of application for permit to enlarge grocery store in residential area.].

. Bankoff v. Board of Adjustment of Wagoner County, see note 13, supra; Banks v. City of Bethany, see note 13, supra; Application of Sha-did, see note 13, supra.

. Banlcs v. City of Bethany, see note 13, supra; Bailey v. Uhls, see note 13, supra.

. Racine County v. Cape, 2002 WI App 19, ¶ 5, 250 Wis.2d 44, 639 N.W.2d 782, 784 [Whether a particular use is an identifiable change of a legal *6nonconforming use is a question of law reviewed de novo.]; Hugoe v. Woods Cross City, 1999 UT App 281, ¶ 6, 988 P.2d 456, 457 [Question of use of property as a legal nonconforming use presents a question of law.]; State ex rel. Broolcs v. Hartland Sportsman’s Club, Inc, see note 11, supra [Determination of legal nonconforming use involves application of facts to legal standard presenting question of law reviewable de novo.]. See also, Hannigan v. City of Concord, 144 N.H. 68, 738 A.2d 1262, 1265 (1999) [Interpretation of zoning ordinance and the determination of whether a use is accessory use are questions of law for reviewing court to decide.]; Christy's Realty Limited Partnership v. Town of Kittery, 663 A.2d 59, 61 (Me. 1995)[Whether a proposed use falls within a given category contained in a zoning ordinance is a question of law.]; McMahon v. Kingston Township Board of Supervisors, 771 A.2d 96, 98 (Pa.Cmwlth. 2001)[Whether a proposed use falls within a given category specified in a zoning ordinance is a question of law.]; Davis v. Town of Stallings Board of Adjustment, 141 N.C.App. 489, 541 S.E.2d 183, 186 (2000) [Whether owner's video store was an adult establishment presented a question of law, warranting de novo review.]; Graham v. Itasca County Planning Commission, 601 N.W.2d 461, 467 (Minn.App. 1999) [The application of an ordinance to established facts is a question of law.]. But see, Bonaventure International, Inc. v. Borough of Spring Lake, 350 N.J.Super. 420, 795 A.2d 895, 904 (2002) [Issue of expansion from a nonconforming use is a question of mixed law and fact.]; Heilker v. Zoning Board of Appeals, 346 S.C. 401, 552 S.E.2d 42, 47 (2001)[A zoning board determination regarding whether a particular activity or purpose constitutes use of property is a finding of fact.]; Bauer v. City of San Diego, 75 Cal.App.4th 1281, 89 CaI.Rptr.2d 795, 802 (1999) [Generally, the determination of whether an existing legal nonconforming use should continue to be allowed under grandfathered provisions involves mixed questions of law and fact.].

. See, Town of Salem v. Wickson, 146 N.H. 328, 770 A.2d 1120,1122 (2001)[AIthough stockpiling earthen materials was not substantially similar to prevailing nonconforming use, to determine substantial change, court considers the extent the use in question reflects the nature and purpose of the prevailing use; whether use is different in character, nature and kind; and whether use will have substantially different effect on neighborhood.]; Turbat Creek Preservation v. Town of Kennebunkport, 2000 ME 109, 753 A.2d 489, 492 (2000) [Determining that use of boathouse was not grandfathered use, but recognizing that grandfathering nonconforming use requires that proposed use reflect the nature and purpose of use prevailing when ordinance was enacted and may not differ in quality or character, as well as in degree from original use or different in kind in its effect on neighborhood.]; DiBlasi v. Zoning Board of Appeals of the Town of Litchfield, 224 Conn. 823, 624 A.2d 372, 376 (1993) [Finding that change in use from business office to medical office was not sufficiently different in character to constitute a change in use.]; Derby Refining Co. v. City of Chelsea, 407 Mass. 703, 555 *7N.E.2d 534, 539 (1990) [Whether change or expansion occurs the court inquires into the nature and purpose of prior use; the difference in quality or character; and whether use is different in kind in its effect on the neighborhood.]; Jones v. Rommell, 521 A.2d 543, 545 (R.I. 1987) [In dispute over change in use based on inadequate number of parking spaces, the court recognized that a change of use results when the proposed us is substantially different from the nonconforming use to which the premises were previously put.]; Bonaventure International, Inc. v. Borough of Spring Lake, see note 16, supra [Although restaurant improperly expanded use, the court recognized that present use must be substantially similar to use at time it became nonconforming and focus is on the quality, character and intensity of expansion.]; Zoning Board of Adjustment of City of Philadelphia v. Libros, 85 Pa.Cmwlth. 485, 482 A.2d 1181, 1183 (1984) [Use did not involve significantly greater capital equipment or greatly expanded operations to constitute a new use.]. See generally, Eichelberger, E., Annot., "Change in Type of Activity of Nonconforming Use as Violation of Zoning Ordinance," 61 A.L.R. 4th 903 (1988).

.The Code of the City of Norman, Zoning Ordinance § 22-450 provides in pertinent part:

"(10) BOARDING HOUSE. A residential building, other than a hotel, where, for compensation and by prearrangement for definite periods, on a monthly or longer basis, rooms and meals are provided to more than two (2) persons who are not members of the resident manager’s family.”

. The City of Norman relies on City of Long Beach v. California Lambda Chapter, 255 Cal. App.2d 789, 63 Cal.Rptr. 419 (1967); Phi Kappa Iota Fraternity v. Salt Lake City, 116 Utah 536, 212 P.2d 177 (1949); and Coleman v. City of Walla Walla, 44 Wash.2d 296, 266 P.2d 1034 (954) in support of its argument that fraternity houses differ from boarding houses. However, we find these cases unpersuasive as applied to the facts of the present case. The City also argues that throughout the Code, fraternity houses and boarding houses are subject to a multitude of different requirements. We recognize that different requirements relate to fraternity houses and boarding houses under the Code, nevertheless, the fact that different requirements apply, is not determinative of whether the both uses are substantially similar in character.

. DiBlasi v. Zoning Board of Appeals of the Town of Litchfield, see note 17, supra [Change in intensity of use is not an acceptable criterion for determining whether proposed use is a change is use.]; City of Jewell Junction v. Cunningham, 439 N.W.2d 183, 186 (Iowa 1989)[Recognizing that increase in business alone does not constitute an illegal extension of nonconforming use, the court held that facility change from care of elderly persons with mental problems to care of younger residents with records of mental illness did not change legal nonconforming use.]; Keller v. City of Bellingham, 92 Wash.2d 726, 600 P.2d 1276, 1279 (1979)[Intensification of a nonconforming *8use is permissible if nature and character is unchanged and substantially the same facilities are used.]; Institute for Evaluation and Planning, Inc. v. Board of Adjustment, 270 N.J.Super. 396, 637 A.2d 235, 237 (1993) [Mere increase in intensity of use is not fatal to continuation of nonconforming use.]; Waukesha County v. Seitz, 140 Wis.2d 111, 409 N.W.2d 403, 406 (1987) [Although increase in volume, intensity, or frequency of use, coupled with some element of identifiable change or extension will invalidate legal nonconforming use, mere increase in volume, intensity, or frequency of nonconforming use is not sufficient to invalidate it.]; See also, Phillips v. Zoning Commissioner of Howard County, 225 Md. 102, 169 A.2d 410 413 (1961) [Recognizing that mere intensification of non conforming use is permissible as long as the nature of the use has not substantially changed.].

See generally, Eichelberger, E., Annot., "Change in Volume, Intensity, or Means of Performing Nonconforming Use as Violation of Zoning Ordinance,” 61 A.L.R.4th 806 (1988). But see, Huff v. Board of Adjustment of City of Independence, 695 S.W.2d 166, 168 (Mo.App. 1985) [Whether change in use is substantially similar is neither relevant nor decisive because the ordinance clearly prohibits a change from one nonconforming use to another.].

. The Code of the City of Norman, Zoning Ordinance § 22-419, see note 9, supra; City of Sugar Creek v. Reese, see note 11, supra; State ex rel. Broolcs v. Hartland Sportsman’s Club, Inc, see note 11, supra.

. The Code of the City of Norman, Zoning Ordinance § 22-419, see note 9, supra.