Grindlay appeared in Masterton District Court before Justice of the Peace David Baker in the afternoon, charged with arson. Duty lawyer Peter Stevens said Grindlay consented to being remanded in custody.
Mr Baker remanded Grindlay in custody to reappear on December 10.
Grindlay is an architectural designer and the sole director of Surtec Group Consultants Ltd, which lists the property as the company's address.
Fire investigators remained at the site yesterday morning to determine the cause of the fire.
Featherston fire chief Colin McKenna said he called in an additional unit from Greytown to help contain the blaze.
Head of CIB, Masterton, Scott Miller, said they were called out and secured the scene on arrival.
Mr Miller said there was no one in the property which was being renovated.
The accused was found a short distance away, arrested and charged, he said.