Help I’m looking to fill a gap between a recently installed cast iron fireplace insert and a wooden surround. The original wooden surround was damaged and could not be used so a new one was purchased. I think I may be able to get the gap a bit smaller by readjusting the surround a bit but there will still be a gap. I’ve done research this morning and I’ve seen several items which may do the job, fire proof expanding foam, high performance wood filler and heat resistant plaster. Not sure what the best way forward is any suggestions would be great.
[here is the gap ](https://imgur.com/gallery/GK9NZDf)