One appliance and crew from Beaconsfield, two from Hillingdon, one from Ruislip, one from Slough, one from Langley and one from Maidenhead attended with four officers. The barn contained a large quantity of hay, farm machinery and horse boxes.
Firefighters used two main jets, two hose reels, four sets of breathing apparatus and fans. Relief crews from Gerrards Cross, Amersham and High Wycombe attended during the night and morning.
A large smoke plume drifted across the A40 in the direction of Denham, and residents were advised to stay in and keep windows shut. This message was issued again at 11am on Thursday.
A crew from Gerrards Cross and an officer remain at the scene on Thursday morning.