The High Court's ruling on the Minister for Justice, Equality and Law Reform's Roscommon holiday home has completely vindicated his actions, Mr McDowell has said.
He also said he would sue Roscommon County Council for compensation to pay for water damage to his property since the case began.
"The building has been very seriously damaged as the result of the unlawful refusal of the council to allow me to complete it," he said. "We were accused of breaking the law by a local authority which has been itself found to have broken the law."
Mr McDowell said nobody should "ever be treated in the way that myself and my wife were treated".
The county council had mislaid vital planning documents and ignored correspondence from his lawyers and seriously misled the public about his conduct.
Mr McDowell told journalists: "Naturally, both myself and my wife feel vindicated by the High Court. We have always contended that we have scrupulously adhered to the law. There is some degree of satisfaction arising out of that."
He and his wife, Prof Niamh Brennan, had been scrupulous in their instructions to the builders to make sure that they obeyed planning law, "and they did so".
The couple would have breached the planning laws if they had built the house in the way that the county council had ordered them to do.
Regretting the need to take the local authority to court, Mr McDowell said it was wrong that he had had to do so to vindicate his right to have a fair decision made in a proper way.
"I am very confident that nobody will be treated in that way again where they are suddenly being told by the media that it is being contended that you have broken the law when you haven't," he added.
"The shock of having your private affairs catapulted into the public domain is obviously something that would only happen to a Minister. But the economic consequences of a decision of that kind for a couple in similar circumstances to ours who are not in the public eye could be huge.
"I hope that nobody has ever been treated like that in private life and I hope that nobody has ever had to slink away having received such an unjust treatment at the hands of a local authority."
Roscommon County Council had given no warning that it was about to refuse him permission to finish construction of the house.
"We were never consulted. No explanation was ever given prior to the decision of the way in which the county council was thinking of exercising its power. I certainly think that there are lessons to be learned," he said.
The public was "seriously misled" about the reasons the council had made its decision. It had invented one of its grounds for action against him.
He was still waiting for an explanation from the council as to how that had happened.
"High standards are necessary in the administration of the planning law. When people instruct their builders and their building company to comply with those high standards, they are entitled that those high standards will be reciprocated by those with whom they deal in the public system," Mr McDowell said.
Building work would begin as soon as the relevant orders had been made by the High Court. "Serious damage, I have to tell you, has already been done to the house."
The Minister said that there was a question about how much of the cost of the repair of the house could be put down to water leaks caused "directly from the unlawful acts of the county council".