Venue that allows bbq near Hertfordshire

Hi, does anyone know of a venue near Hertfordshire that would allow a BBQ instead of a 3 course meal? Found one where the catering option showed BBQ items, only to be told that due to thatched roofs they won’t allow a BBQ the caterer can only offer BBQ style grilled food.
It was a barn wedding on the Herts/Essex border.
Any help is greatly appreciated.