Opinion by
Judge Crumlish, Jr.,For the past nine years, Jared A. Cooper and the City of Greensburg (City) have been engaged in litigation over Cooper’s right to construct a gasoline station on land which he owns in the City. Hopefully, this will be the last chapter in that struggle.
' Presently before us is the City’s' appeal from an order of the Court of Common Pleas of Westmoreland *248County, sitting en banc, which dismissed the exceptions filed by the City and several of its residents (Intervenors) and which affirmed the decree nisi of the court which granted Cooper’s petition for mandamus and ordered the issuance of the permits required for construction of Cooper’s gasoline station. We affirm.
We will first summarize the facts and complicated litigation history of this case. In 1967, Cooper acquired 66.928 acres of land in the City. The land was part of territory which had been annexed by the City from a neighboring township in 1958. When the City annexed the territory, it had a zoning ordinance which provided that territory annexed to the City would automatically become zoned single-family residential (R-l). In June, 1967, Cooper applied for certain building permits for the portion of this newly annexed land which he had acquired from the City. One of the permits, the one with which we are here concerned, was for the construction of a gasoline service station on approximately 0.575 acres of the tract. The permit application was refused. After much litigation, this Court, in an opinion written by Judge Wilkinson, held invalid the City’s automatic zoning ordinance and ordered the necessary certificates of compliance and occupancy to be issued. Cameron v. Greensburg, 3 Pa. Commonwealth Ct. 209, 281 A.2d 271 (1971).1 After this decision, Cooper, although he had lost a prospective tenant during the pendency of the litigation, began excavation work on his land in preparation for new tenants. However, prior to our decision in *249Cameron and prior to Cooper’s starting the new excavation, the City enacted a new ordinance which zoned Cooper’s lands as R-l. With regard to this new ordinance, we stated in Cameron, sufra, that, although it was apparently validly enacted, it was not “pending” at the time of Cooper’s 1967 application for certificates of compliance and occupancy and, therefore, it could not destroy Cooper’s vested right to obtain the certificates. In the meantime, in April, 1969, the City had approved a subdivision plan submitted by Cooper which included the portion intended for the gasoline service station albeit with a slight variation in the metes and bounds description of the tract from that which was contained in Cooper’s 1967 application. On February 16, 1973, Cooper entered into an option agreement with Boron Oil Company (Boron) for the sale of the 0.575 acre tract. Although Boron was not the same tenant contemplated by Cooper in his 1967 application, it also intended to use the land as a gasoline, service station.
On June 14,1973, acting upon directions given bim by the City’s zoning officer, Cooper applied for new compliance permits and certificates of occupancy in accordance with the provisions of the 1971 zoning ordinance. The application was refused for the reason that the use intended by Cooper was not permitted under the 1971 ordinance.
In October, 1973, Cooper filed a complaint in mandamus seeking to compel the City’s zoning officer to issue the permits and certificates requested in the June 14, 1973 application. Approximately one hour after Cooper filed his complaint, the court below, on Cooper’s motion, granted summary judgment in mandamus. The City’s petition to open the judgment was dismissed. Once again, the City appealed to this Court. We vacated the lower court’s order of sum*250mary judgment. and remanded the' matter . for .the making of a record. City of Greensburg v. Cooper, 14 Pa. Commonwealth Ct. 419, 322 A.2d 152 (1974). In an opinion, written by Judge. Kramer, we held that our decision in Cameron v. Greensburg, supra, gave. Cooper a.“vested right” to the permits requested in the 1967 application, not because he had purchased his property prior to the effective' date of the 1971 zoning ordinance, but, rather, because the, permits had been applied'for. before the, 1971. zoning ordinance was “pending.” In City of Greensburg v. Cooper, supra, we also held that there was an issue of fact as to whether Cooper’s original compliance and building permits (the. ones, issued after our decision in Cameron v. Greensburg), had been abandoned because they had not been renewed. Apparently, the lower court did not have Cooper’s 1973 application before it, only his 1971 application and the 1973 subdivision plan. Finding that the court below .not only misinterpreted our decision in Cameron v. Greensburg but also failed to recognize the existence of issues of fact, we-.remanded the matter. ■ ,
In May, 1975, after hearings were held, the court, below again ordered that the requested, permits be issued.' The.- City’s exceptions were dismissed and the dismissal was affirmed by the court belpw sitting. en banc. The City has again appealed to this-Court. , :
It is well settled that mandamus is an extraordinary . writ ■ which lies to compel performance of a ministerial' act or mandatory duty where there is a clear legal right in the plaintiff, a corresponding duty in the defendant, and a want of any other appropriate and adequate remedy. Blystone v. Borough of Forest Hills, 22 Pa. Commonwealth Ct. 395, 349 A.2d 494 (1975). We are asked here to review the propriety of the granting of mandamus, ■ rather than the pro*251priety of granting summary . judgment- therefor. Therefore, we must determine whether the lower, court abused its «discretion or committed an error of lawi. Venneri v. County of Allegheny, 12 Pa. Commonwealth Ct. 517, 316 A.2d 120 (1974). Furthermore, where, as here, a case has been previously remanded so-that a particular-finding can be made, we cannot substitute our findings for those of the lower court, but must determine only whether .sufficient evidence supports' the findings of the lower court.
We have held that one claiming a vested right in a building-permit must establish that the application was made in gobd faith, that a substantial commitment or expenditure was made in justifiable reliance upon the granting of the permit, and- that the permit was issued lawfully under' zoning law then existing. Klavon v. Zoning Hearing Board of Marlborough Twp., 20 Pa. Commonwealth Ct. 22, 340 A.2d 631 (1975).
; The court below found that Cooper had, at the time he filed the 1973 applications,. met all of the requirements placed upon him by the City and therefore had a - vested right to erect a service station on his lot. The City argues that Cooper abandoned the permits which were issued after our decision in Cameron v. Greensburg, supra, by not beginning, construction or renewing them each six months as required by the City’s zoning ordinance. However, the record amply supports the findings of. the court below that Cooper had spent large sums of money for excavation of the land-.and at all times acted «upon the instructions of the City’s. zoning officials as to .the procedure for acquiring and maintaining permits.
Our careful review of the record reveals that the court below was justified in concluding that Cooper satisfied these requirements and, -therefore, had, a *252vested right to building permits for a gasoline service station on his tract.
Next, the City contends that mandamus is not the proper remedy for Cooper. This contention has no merit. In Borough of Monroeville v. Effie’s Ups & Downs, 12 Pa. Commonwealth Ct. 279, 315 A.2d 342 (1974), we held that where a plaintiff has a clear legal right to the issuance of a building permit, mandamus is the appropriate remedy to compel its issuance.
Having concluded that Cooper had a vested right to the issuance of building and compliance permits and that mandamus is the appropriate remedy, we affirm the order of the court below.
The automatic zoning ordinance was held invalid because the effect was to cause lands to be zoned without following the notice and hearing procedure required by Section 4114 of the Third Class City Code, Act of June 23, 1931, P.L. 932, 53 P.S. §39114, which was the zoning enabling statute then in effect. (Repealed by Section 1201 of the Act of July 31, 1968, P.L. 805, 53 P.S. §11201.)