Work has begun to make the fire-damaged Locarno building in Swindon safe for investigators to continue their search of the site.
The fire took several hours to bring under control
An examination of the scene had to be abandoned because of fears the blaze may have weakened the structure.
Scaffolding was being erected around the abandoned building's bell tower on Thursday.
A Wiltshire fire brigade spokesman said the cause of fire would not be known until the probe was completed.
"Scaffolding is going up around the bell tower," he said.
Tower 'at risk'
"And when it is safe, we can go on and complete a full search and a full investigation.
"That is not likely to be until the weekend"
Around 50 firefighters tackled a fire at the Grade II listed building on Wednesday morning.
The fire was reported at 0250 BST and it took several hours for crews to bring it under control.
At one stage it was thought the bell tower was at risk of falling down, but structural engineers later said they believed it would not collapse.
The High Street was closed both ways on Wednesday morning as a result of the fire.
The building was seriously damaged by fire in May 2003.