Fire raged through the offices at OFP Timber Homes on the Sandwich Industrial Estate when 40 firefighters battled against "fearful weather" to save the factory.
Company director Neil Brannan said he was devastated when he arrived on site after a phone call just after 3am from the Kent Fire and Rescue Service.
He said: "The office was well ablaze and that part of our building is absolutely gutted. Thankfully most of the factory is okay and it seems our fire doors worked.
"Eleven people work in the office and we back up daily on our computers, but obviously it will take us a couple of days to be sorted.
"The fire is certainly a significant interruption for the business, but we are going to keep going and will work over Christmas to make sure we are up and running in the new year.
"We don’t let our clients down. We will be back on our feet as soon as possible. The irony is that we were in the process of moving the offices elsewhere on the industrial estate."
* For full story see page three, East Kent Mercury, December 15.