Fire crews say an early morning call of nature appears to have saved a man’s life this morning.

When his Coburg bedroom went up in flames, the man was not woken because the Cash St bungalow had no working smoke alarms.

So it was lucky his bladder was full about 5am.

“He actually had to go to the toilet,’ MFB commander David Wood told 3AW.

“That’s really the only thing that’s saved his life.”

The man ran to get water but the fire quickly engulfed his bedroom.

MFB crews were on the scene within six minutes and brought the blaze under control within 10 minutes, stopping it from spreading to the house.

It’s believe a heater caused the fire.