There’s a long standing fear that using a timber frame for your home or extension makes it more likely to burn down but like a lot of ideas, this is one that isn’t based in fact. For starters, structural timber is not quick to burn. Firefighters have shown in research that they would prefer to enter a timber frame building that is on fire than other styles for a number of reasons including that the burn and char rate is predictable and that the wood is not explosive.
Added to that, all timber frames that are commercially available have to be manufactured and erected in compliance with certain regulations and warranties. These are designed to protect against things like fire as much as possible. A good way to see it is that lenders and insurance companies make no difference between masonry and timber frame constructions in terms of fire risk or general rating.