A NSW man was killing time in his shed earlier this week when he came across a monster lizard in his backyard.

Eric Holland was quick enough to snap a photo of the estimated 1.5-metre lace monitor on the side of his Thurgoona home.

"I was just doing a repair job in my shed when I opened the door and I saw this huge thing run across the ground and out of sight," Mr Holland said.

"I went inside after I saw it in the backyard and heard a banging noise coming from the side of the house.