RMS estimated $4 billion to $8 billion of insured losses from wildfires in Northern California, Oregon and Washington as of Sept. 20.

The estimated losses include property damage, evacuation and smoke damage, additional living expenses and business interruption across residential, commercial and industrial lines. Smoke and evacuation losses contributed about 20% of losses in Northern California and about 35% of losses in Oregon and Washington.

Wildfires in the Western U.S. have burned through more than 4 million acres and damaged or destroyed more than 13,500 structures as of Sept. 20, with additional losses likely as many wildfires are still ongoing in Northern California, Oregon and Washington.

Michael Young, vice president of product management at RMS, said 30% to 60% of structures had survived the wildfires due to wildfire-resistant vents and other factors in building science that increased the survivability of these structures.

Young also emphasized the need to duplicate similar measures at scale as an effective step toward mitigation if the ongoing wildfires represent the "new" normal.