A fire at Northern's Plumbing Supplies, Tanunda is not suspicious.
The damage bill, including stock that was in the building, is well into the hundreds of thousands.
Fire has engulfed the back of the Northern's Plumbing Supplies building on Murray Street, Tanunda.
Fortunately there were no customers in the building and all staff have been accounted for.
Black smoke curled high into the sky as flames licked above the top of the building and several minor explosions were heard as fire crews battled to control the blaze.
Tanunda CFS were at the scene shortly after the fire had started early Tuesday afternoon and contained the blaze to the plumbing shop.
At one stage embers from the fire threatened nearby businesses but quick action by emergency services contained the fire.
Many nearby residents swarmed to the scene but were ushered away as police warned that toxic fumes caused by burning plastic fittings were emanating from the blaze.
At one stage it was feared oxy-acetelyne bottles on the premises could explode to cause a major incident but fortunately the danger was averted.
Police cornered off the area between the intersection of Murray Street and Magnolia Street and Murray Street and Bridge and Hobbs Street for safety reasons and traffic was diverted for several hours after the fire was brought under control.
The back of the building collapsed after the fire was contained.
It is not yet know what caused the fire or how much the damage bill will be.