Arnold Mouat was found dead in his home in Bo’ness on Saturday.
The 64-year-old was reported missing on July 7 having been last seen by his family the previous day in his house in Panbrae Road
A large-scale search was held in a bid to find him, involving divers, mountain rescue and police dogs.
In a statement issued through PIRC, the family of Arnold Mouat said: “As a family we are devastated by the loss of a loving husband and father and we are now trying to come to terms with what has happened.
“We would like to thank everyone for the support we have received over these last few difficult weeks but would now ask for our privacy to be respected so that we have the time and space to grieve in peace.”
A watchdog investigation will examine how police officers searched the property of Mr Mouat who was found dead in his garage four weeks after his disappearance.
The body of Arnold Mouat was discovered by a family member at the weekend after a four-week search including Police Scotland divers and the force helicopter.
The Police Investigations & Review Commissioner (Pirc) yesterday said its investigation into Police Scotland’s handling of the case would focus on the force’s initial response, including its search of the 64-year-old’s home.
The case has once again heaped pressure on the leadership of Police Scotland, with the Scottish Conservatives claiming the public is “losing faith” in the national force.
A Pirc spokeswoman said: “The Police Investigations & Review Commissioner is conducting an investigation into the response from Police Scotland to the missing person investigation for Arnold Mouat following a referral from Police Scotland. Mr Mouat, 64, was last seen at his home in Panbrae Road, Bo’ness on the evening of Thursday 6 July. His body was found on Saturday 5 August at his home.
“The investigation will focus on the initial response from Police Scotland including the search of his home address.”
Liam Kerr, the Scottish Conservatives’ justice spokesman, said “There is an increasing mood that a centralised unit is losing its touch locally.”
A Scottish Government spokeswoman said: “Our thoughts are with the family of Arnold Mouat.
“It would not be appropriate to comment on a specific investigation at this time.”