Saskatoon fire investigators say a fire on Friday afternoon caused $30,000 in damage to a Weldon Avenue home.Multiple 911 calls reporting heavy smoke on the 700 block started coming in at 3:23 p.m.Arriving crews said heavy black smoke was coming from the basement and a significant amount of heat.An in-depth investigation determined the fire was intentionally set and Saskatoon police are now involved.Investigators also discovered deficiencies with smoke alarms in the home.Firefighters found no people or pets inside the home at the time of the blaze.