It was not until June 13, 1967, that the plaintiffs finally filed suit against Handler and certain of its officers and directors for breach of contract, negligence and willful and wanton conduct in failing to obtain the permit and for fraud. The defendants first successfully moved to have the suit dismissed as barred by the statute of limitations. That determination was reversed by this court in 1968 in Sabath v. Morris Handler Co. (1968), 102 Ill. App.2d 218, 243 N.E.2d 723, which ruled that it was at the very least a question of fact whether the defendants were barred by their actions from relying on that defense, since it was not reasonable to expect the plaintiff to bring suit during the period from 1961-1965 when "the defendants, by their conduct, recognized their duty and obligation to the plaintiffs and were doing the very things which the plaintiffs desired and requested." ( 102 Ill. App.2d 218, 223, 243 N.E.2d 723, 726.)

Although National posits that the limitations period did not commence until 1979 — the date it claims to have first actually discovered the mistake — the Illinois courts have rejected the "know or ought to know" rule as the time a limitations period begins to run. ( Sabath v. Morris Handler Co. (1968), 102 Ill. App.2d 218, 228-29.) Rather, the statute of limitations commences to run when the party to be barred has a right to invoke the aid of the court to enforce his remedy.

A party may assert estoppel as a bar to the statute of limitations as to other matters; a party's conduct may estop him or her from raising the defense of the statute of limitations. ( Sabath v. Morris Handler Co. (1969), 102 Ill. App.2d 218, 223, 243 N.E.2d 723, 726, relied upon in Beynon Building Corp. v. National Guardian Life Insurance Co. (1983), 118 Ill. App.3d 754, 763, 455 N.E.2d 246, 252.) If a party's conduct has reasonably induced another to follow a course of action that otherwise would not have been followed and that would be to the latter's detriment if he or she did not later repudiate such course of action, an estoppel arises to prevent injustice or fraud. Sabeth v. Morris Handler Co. (1969), 102 Ill. App.2d 218, 223, 243 N.E.2d 723, 726. It is not essential that the representation or conduct was fraudulent in the strict legal sense or done with an intent to mislead or deceive. Rather, the test is whether, in all the circumstances of the case, conscience and duty of honest dealing should deny one the right to repudiate the consequences of his representations or conduct. Although no duty ordinarily exists to apprise an adversary of his rights, one cannot justly or equitably lull his adversary into a false sense of security, causin

If those cases correctly apply the law of Illinois, plaintiff's claim in this case is clearly barred. Coumoulas v. Service Gas Incorporated, 10 Ill.App.3d 273, 293 N.E.2d 187 (1973); Board of Education v. Perkins Will Partnership, 119 Ill.App.2d 196, 255 N.E.2d 496 (1970); Wilson v. White Motor Corp., 118 Ill.App.2d 436, 254 N.E.2d 277 (1969); Sabath v. Morris Handler Co., 102 Ill.App.2d 218, 243 N.E.2d 723 (1968); Board of Education v. Joseph J. Duffy Co., 97 Ill. App.2d 158, 240 N.E.2d 5 (1968); and Simoniz Co. v. J. Emil Anderson Sons, Inc., 81 Ill.App.2d 428, 225 N.E.2d 161 (1967). As plaintiff points out, however, the Illinois Supreme Court has applied the discovery rule in three recent cases: first, in Rozny v. Marnul, 43 Ill.2d 54, 250 N.E.2d 656 (1969), a property owner's action against a surveyor who had placed an "absolute guarantee for accuracy" on an incorrect plat of survey; second, in Williams v. Brown Manufacturing Co., 45 Ill.2d 418, 261 N.E.2d 305 (1970), a strict liability action for personal injuries resulting from the operation of a trencher which was allegedly in a defective and dangerous condition when it left defendant's control; and third, in Lipsey v. Michael Reese Hospital, 46 Ill.2d 32, 262 N.E.2d 450 (1970), a patient's action for medical malpractice.

The complaint herein was filed March 16, 1971, approximately seven years after that time. Illinois courts have uniformly held that the statute of limitations for actions for property damage resulting from negligence begins to run when the negligent act is committed, not from the time when the claimant party actually suffered damage as a result thereof; e. g., Board of Education v. Perkins Will Partnership, 119 Ill. App.2d 196, 255 N.E.2d 496 (1970); Wilson v. White Motor Corp., 118 Ill. App.2d 436, 254 N.E.2d 277 (1969); Sabath v. Morris Handler Co., 102 Ill. App.2d 218, 243 N.E.2d 723 (1968); Board of Education v. Joseph J. Duffy Co., 97 Ill. App.2d 158, 240 N.E.2d 5 (1968); Simoniz Company v. J. Emil Anderson Sons, Inc., 81 Ill. App.2d 428, 225 N.E.2d 161 (1967). The two Board of Education cases arose out of alleged negligent design and construction of a school building.

Plaintiff correctly asserts that if his charge was untimely filed because of defendant's misleading conduct, defendant will be estopped from raising the limitations period as a defense. (See Sabath v. Morris Handler Co. (1968), 102 Ill. App.2d 218, 223, 243 N.E.2d 723.) But defendant will only be estopped if it was conduct initiated by defendant which induced plaintiff not to act.

• 7 Plaintiff further contends that the defendant is estopped from raising the defense of the statute of limitations because of its conduct. We agree that estoppel may be a bar of the defense of the statute of limitation as well as to other defenses. ( Sabath v. Morris Handler Co. (1968), 102 Ill. App.2d 218, 223, 243 N.E.2d 723.) "If a party's conduct has reasonably induced another to follow a course of action that otherwise would not have been followed, and which would be to the latter's detriment if he could not later repudiate such course of action, an estoppel will arise to prevent injustice * * *." ( Sabath v. Morris Handler Co. (1968), 102 Ill. App.2d 218, 223, 243 N.E.2d 723.)

• 2-4 A cause of action based on negligence may be said to accrue when all the elements of the action are present, including a legal duty, the breach of that duty, and injury resulting from such failure. ( McClure v. Hoopeston Gas Co. (1922), 303 Ill. 89, 96.) An action in tort has been held to "accrue" as that term is used in limitation statutes, at the time of wrongful invasion of personal or property rights, even though the nature and full extent of the injury or damages is not then determined. ( Sabath v. Morris Handler Co. (1969), 102 Ill. App.2d 218, 229; Austin v. House of Vision, Inc. (1968), 101 Ill. App.2d 251, 256-257.) Here, an injury occurred at the time of the negligent installation, and plaintiff at that time would have been entitled to sue to recover damages to remedy the defective installation.

The weight of authority in the United States is similarly disposed. Thompson v. Phenix Ins. Co. (1890), 136 U.S. 287; Bergeron v. Mansour (1st Cir. 1945), 152 F.2d 27; Munger v. Boardman (Ariz. 1939), 88 P.2d 536; Baker-Matthews Mfg. Co. v. Grayling Lumber Co. (1918), 134 Ark. 351, 203 S.W. 1021; Sumrall v. City of Cypress (1968), 258 Cal.App.2d 565, 65 Cal.Rptr. 755; Industrial Indemnity Co. v. Industrial Accident Com'n. (Cal.App. 1953), 252 P.2d 649; Miles v. Bank of America Nat. Trust Savings Ass'n (Cal.App. 1936), 62 P.2d 177; Sabath v. Morris Handler Co. (1968), 102 Ill. App.2d 218 243 N.E.2d 723; Safeway Stores Inc. v. Wilson (1962), 190 Kan. 7, 372 P.2d 551; Clover Splint Coal Co. v. Lorenz (1937), 270 Ky. 676, 110 S.W.2d 457; Chandlee v. Shockley (1959), 219 Md. 493, 150 A.2d 438; LaBonte v. New York, New Haven Hartford R.R. (1960), 341 Mass. 127, 167 N.E.2d 629; MacKeen v. Kasinskas (1956), 333 Mass. 695, 132 N.E.2d 732; Hayes v. Gessner (1944), 315 Mass. 366, 52 N.E.2d 968; Voorheis v. Peoples Mut. Ben. Soc. (1892), 91 Mich. 469, 51 N.W. 1109; Croop v. Odette (1960), 219 N.Y.S.2d 805; Douglass v. Douglass (Okla. 1947), 188 P.2d 221; McMeekin v. Prudential Ins. Co. of America (1944), 348 Pa. 568, 36 A.2d 430; Armstrong v. Levan (1885), 109 Pa. 177, 1 A. 204; Wolf v. S.H. Wintman Co. (1961), 92 R.I. 470, 169 A.2d 903; Kraus v. Morris (Tex. 1922), 245 S.W. 450; McLaughlin v. Blake (1957), 120 Vt. 174, 136 A.2d 492; Kreielsheimer v. Berryman (1915), 85 Wn. 175, 147 P. 871. We now respond to the prophecy and promise held out in the Donnella and Schuldt cases,

Under Illinois law, a defendant may be estopped by his conduct from asserting the statute of limitations as a defense. See, e.g., Arthur L. Larsen Company, Inc. v. Shefner, 27 Ill. App.3d 562, 327 N.E.2d 257, 258 (2nd Dist. 1975); Sabath v. Morris Handler Company, 102 Ill. App.2d 218, 243 N.E.2d 723, 726 (1st Dist. 1968). The estoppel issue usually arises in situations where the parties, or their insurers, engage in negotiations regarding a claim prior to the expiration of the statute of limitations.