WA Arson Squad detectives have charged a 40-year-old man in relation to bushfires near Perth earlier this year that were declared an insurance catastrophe.

Police allege the man used a mechanical device to remove a padlock on a sea container on his property, igniting the Wooroloo bushfire.

The blaze was first reported to the fire services on February 1 and continued burning over the following week amid adverse conditions, destroying 10,750 hectares of bushland, 86 homes and numerous sheds, vehicles and livestock.

The Perth Hills bushfires caused insurance losses of $91 million, with some 1000 claims received, according to the Insurance Council of Australia. The fires marked the first catastrophe declared this year.