Suspicious fire damages Sydney house

Police suspect someone deliberately lit a fire that caused significant damage to a house in Sydney's west.

Emergency services were called to Guildford Road in Guildford just before 9.30pm on Saturday to find the home well alight.

Firefighters extinguished the blaze but the home sustained significant damage.

No one was home at the time.

Police believe the fire was deliberately lit and have urged anyone who witnessed suspicious activity in the area to come forward.