
160 S.E.2d 719 (1968)
273 N.C. 559
Grover P. SNOW
v.
NORTH CAROLINA BOARD OF ARCHITECTURE.
No. 521.
Supreme Court of North Carolina.
May 1, 1968.
*724 William T. McCuiston, Raleigh, for appellant.
Albright, Parker & Sink, Raleigh, for appellee.
LAKE, Justice.
The judgment of Mallard, J., terminated the action instituted by the plaintiff on 31 May 1966, no appeal from that judgment having been perfected. That judgment dealt with the right of the plaintiff to a renewal of his certificate of admission to the practice of architecture for the period ending 30 June 1966. It determined that the plaintiff, having tendered to the board on 26 March 1966 the required fee and penalty for the renewal of his certificate, was entitled, as a matter of *725 law, to such renewal as of that date. The judgment specifically stated that it did not relate to any action taken by the board after 31 May 1966. The validity of the order of the board, dated 29 June 1966, is, therefore, not res judicata by reason of the judgment of Judge Mallard, nor did the pendency on that date of the action before Judge Mallard suspend the statutory authority of the board to consider and pass upon an entirely different matter.
G.S. § 83-11 provides:
"Annual renewal of certificate; fee. Every architect continuing his practice in the State shall, on or before the first day of July in each year, obtain from * * * the North Carolina Board * * * a renewal of his certificate for the ensuing year upon the payment of a fee in such amount as may be fixed by the Board * * * and upon failure to do so shall have his certificate of admission to practice, revoked, but such certificate may be renewed at any time within one year upon the payment of the prescribed renewal fee and an additional five dollars ($5.00) for late renewal."
Judge Mallard correctly concluded that this statute gives to the architect who fails to pay the prescribed renewal fee on its due date the right to pay the fee thereafter, within the next twelve months, and obtain a renewal of his certificate, this being an absolute, unqualified right so far as mere delay in payment of the fee is concerned. As to that the board has no discretion. The complaint in the action heard by Judge Mallard alleged that the plaintiff had tendered the fee and penalty, that the board had nevertheless refused to renew his certificate and that the plaintiff was entitled to an order in the nature of a mandamus requiring the board to issue the renewal. That was the question before Judge Mallard and that was what his judgment, dated 13 July 1966, determined. It determined nothing except that the plaintiff was entitled to a renewal of his certificate authorizing him to engage in the practice of architecture from 26 March 1966 to and including 30 June 1966.
The present action heard by Judge Olive does not relate to the matter determined by Judge Mallard, but relates solely to the authority of the board to refuse to renew the certificate, for a period beginning after 30 June 1966, for a cause other than the nonpayment of the renewal fee. The authority of the board to revoke, for cause, the renewal issued pursuant to Judge Mallard's judgment is a moot question not before us on this appeal since it is conceded, and plainly appears from the record, that the order of the board did not take effect until 8 July 1966, when it was served upon the plaintiff, at which time the renewal issued pursuant to the judgment of Judge Mallard had expired by lapse of time.
The judgment of Judge Mallard, entered after the expiration of the renewal period with which it was concerned, was not a vain thing. It established that the plaintiff was entitled to a certificate as of 26 March 1966, so that any otherwise lawful practice of architecture by him from 26 March 1966 to 30 June 1966, inclusive, was not unauthorized practice and would not, for that reason, justify a refusal by the board to renew his certificate for a subsequent period. The validity of the order of the board, dated 29 June 1966, which was the order before Judge Olive, is to be determined, therefore, as if the board had on 26 March 1966 accepted the tender of the renewal fee by the plaintiff and had then issued to him a renewal of the certificate, such renewal expiring at the end of 30 June 1966. Such action by the board would not preclude it from subsequently considering and acting upon charges of conduct by the certificate holder which, if true, would constitute cause for revocation of the certificate.
Chapter 150 of the General Statutes applies to the revocation of a license or *726 certificate issued by the defendant board. G.S. 150-10 provides that every licensee shall be afforded notice and opportunity to be heard before the board takes any action to withhold the renewal of his license for any cause other than failure to pay a statutory renewal fee. G.S. § 150-11(b) prescribes the contents of such notice. The letter of the board to the plaintiff, dated 3 June 1966, complies with these requirements. G.S. § 150-11(c) provides:
"(c) If the licensee * * * does not mail a request for a hearing within the time and in the manner required by this section, the board may take the action contemplated in the notice and such action shall be final and not subject to judicial review." (Emphasis added.)
G.S. § 150-12 provides that such notice "may be served either personally or by an officer authorized by law to serve process, or by registered mail, return receipt requested * * *." The complaint in the present action does not allege that this notice was not so served. What the complaint alleges is that the plaintiff did not, between 31 March 1966 and 30 June 1966, receive notice that his license had been suspended or revoked. It appears from the record that the notice of 3 June 1966 was sent by "registered mail, receipt requested," and that the plaintiff received it on 4 June 1966. Judge Olive found as a fact that "the plaintiff was given proper notice by the defendant in accordance with G.S. § 150-11 of the contemplated action to withhold the plaintiff's certificate to practice architecture for cause." The record supports this finding. It follows that the board had jurisdiction, both of the subject matter and of the person of the plaintiff, at the time of its order dated 29 June 1966. The plaintiff did not request a hearing by the board. Consequently, by the express terms of G.S. § 150-11(c), the board was empowered to determine the matter and its order became final and not subject to judicial review.
G.S. § 150-21 provides:

"Service of written decision.Within five days after the decision is rendered the board shall serve upon the person whose license is involved a written copy of the decision, either personally or by registered mail. If the decision is sent by registered mail it shall be deemed to have been served on the date borne on the return receipt."
Judge Olive found that the plaintiff was given proper notice of its decision in accordance with G.S. § 150-21. The brief of the defendant in this Court contains a statement to the effect that the decision of the board, dated 29 June 1966, was first circulated to the members of the board in order to obtain their approval as to its form and, thereafter, was dispatched by registered mail to the plaintiff on 6 July 1966, and he signed a receipt for it on 8 July 1966. In the absence of a stipulation to this effect by the plaintiff, we cannot base our decision upon this statement of fact in the defendant's brief, the record being silent on that point. Furthermore, the defendant's own "Statement of the Case on Appeal," included in the record, by stipulation, as part of "the case and record on appeal," says, "On June 29, 1966, the Board entered its order." There is nothing in the record to indicate any contrary evidence or contention before Judge Olive. We, therefore, must determine whether an order, within the authority of the board when entered by it, and not subject to judicial review as of that time, becomes a nullity by reason of service upon the certificate holder nine days after its entry.
G.S. § 150-20 provides:

"Manner and time of rendering decision.After a hearing has been completed the members of the board who conducted the hearing shall proceed to consider the case and as soon as practicable shall render their decision. * * * In any case the decision must be rendered within ninety days after the hearing." (Emphasis added.)
*727 We think the clear intent of G.S. § 150-20 is that the board loses its authority to render a decision at the expiration of ninety days from the date of the hearing and an order entered thereafter is a nullity, but it was not the intent of G.S. § 150-21 that an order entered within the authority of the board becomes a nullity through a delay in serving it.
G.S. § 150-24 governs the right to and procedure for obtaining judicial review of a decision of the board, where the decision is subject to judicial review. It provides:

"Availability of judicial review; notice of appeal; waiver of right to appeal.Any person entitled to a hearing pursuant to this chapter, who is aggrieved by an adverse decision of a board issued after hearing, may obtain a review of the decision in the Superior Court of Wake County * * * In order to obtain such review such person must, within twenty days after the date of service of the decision as required by § 150-21, file with the board secretary a written notice of appeal, stating all exceptions taken to the decision * * * Failure to file such notice of appeal in the manner and within the time stated shall operate as a waiver of the right to appeal and shall result in the decision of the board becoming final; except that for good cause shown, the judge of the superior court may issue an order permitting a review of the board decision notwithstanding such waiver." (Emphasis added.)
G.S. § 150-33 provides:

"Judicial review procedure exclusive. The provisions of this chapter providing a uniform method of judicial review of board actions of the kind specified in § 150-10 [including revocation of and refusal to renew a license] shall constitute an exclusive method of court review in such cases and shall be in lieu of any other review procedure available under statute or otherwise. * * *"
The plaintiff did not give notice of appeal from the decision of the board. On the contrary, he did nothing until he instituted this action for a mandamus to compel the renewal of his certificate, approximately fourteen months after the decision of the board was received by him. An action for mandamus may not be used as a substitute for an appeal. Young v. Roberts, 252 N.C. 9, 112 S.E.2d 758; Winston Realty Co. v. City and County Planning Board, 243 N.C. 648, 92 S.E.2d 82; Baker v. Varser, 239 N.C. 180, 79 S.E.2d 757; Pue v. Hood, Comr. of Banks, 222 N.C. 310, 22 S.E.2d 896. This extraordinary remedy "is not a proper instrument to review or reverse an administrative board which has taken final action on a matter within its jurisdiction." Warren v. Maxwell, 223 N.C. 604, 27 S.E.2d 721. An action for a writ of mandamus lies only where the plaintiff shows a clear legal right to the action demanded and has no other adequate remedy. Thomas v. State Board of Elections, 256 N.C. 401, 124 S.E.2d 164; Young v. Roberts, supra; Board of Managers of James Walker Memorial Hospital, etc. v. City of Wilmington, 235 N.C. 597, 70 S.E.2d 833; Jarrell v. Snow, 225 N.C. 430, 35 S.E.2d 273; Harris v. Board of Education, 216 N.C. 147, 4 S.E.2d 328. When the statute under which an administrative board has acted provides an orderly procedure for an appeal to the superior court for review of the board's action, this procedure is the exclusive means for obtaining such judicial review. In re Assessment of Sales Tax, 259 N.C. 589, 131 S.E.2d 441; City of Sanford v. Southern Oil Co., 244 N.C. 388, 93 S.E.2d 560; In re State ex rel. Employment Security Comm., 234 N.C. 651, 68 S.E.2d 311; Strong, N.C. Index, 2d Ed., Mandamus, §§ 1 and 4.
The plaintiff having failed, as found by Judge Olive, to perfect his appeal from the order of the board, dated 29 June 1966, the judgment dismissing his action for mandamus was proper.
Affirmed.
