"Considering the size of the blast, and the flames, everybody at this home is extremely lucky," said Puyallup Police Sgt. Dan Pashone.
Nobody involved was injured.
Investigators say the explosion happened about Tuesday at about 9 p.m. when something went wrong with a hash oil lab that was set up under a small portable canopy.
The oil, which is prized for its high concentration of THC, is made through a simple process of using butane to extract the substance from the leaves and branches of marijuana plants.
Deputies believe a spark from a small appliance ignited butane fumes that built up inside the lab.
Officers say there were as many as 10 people outside the home when they arrived. Some ran away, while four people were taken into custody. The infant is in the care of caseworkers from the state's Child Protective Services.
So far one man has been charged with manufacturing a controlled substance and reckless endangerment. Other suspects will likely face charges, as well.
Pierce County investigators say this is the second hash oil lab explosion in three weeks. They believe this represents the tip of the iceberg of a relatively new drug problem as more people experiment with making their own hash oil.
Many law enforcement agencies and fire departments have little or no experience with these kinds of labs, and an effort is underway to provide training so officers and firefighters can recognize the operations.