A man has been arrested after he "lost it" and set his house on fire on Christmas Eve in rural Waikato.

Northern fire shift communications manager Scott Osmond said it was one of two fires overnight in the Upper North Island.

The man was missing as Tahuna firefighters battled the blaze of the man's small 5m x 5m dwelling on Tramline Rd, Patetonga, in the Hauraki area.

Firefighters were called to the Tramline Rd property about 10.20pm last night. St John Ambulance and police were on scene and initially unable to find the man.

However, he was later reported in police custody and is understood to have "lost it" and the set the small house or sleep out ablaze.

Meanwhile, a rural Tauranga house was significantly damaged in a fire that began at 10.15pm.

A Bay of Plenty fire safety officer was sent to the Peers Rd, Omanawa, property to investigate the cause.

Nobody was injured in the blaze.