When wildfire threatens communities, Structure Protection Units (SPU) and Structure Protection Crews (SPC) are the last line of defence between fire and the built environment. Baumanis Timber Contracting deploys trained contract crews and specialized equipment to protect homes, businesses, and critical infrastructure across the Wildland-Urban Interface (WUI) in British Columbia and throughout Canada.
What Are SPU and SPC?
A Structure Protection Unit is a self-contained equipment package designed to create a humidity bubble around structures threatened by wildfire. By maintaining sustained water application on and around buildings, SPUs raise the ambient humidity and wet combustible surfaces, dramatically reducing the likelihood of ignition from radiant heat and airborne embers.
A Structure Protection Crew is the trained personnel who deploy, operate, and manage SPU equipment in the field. Baumanis SPC members hold certifications including WSPP-115 (Wildfire Structure Protection), SPP-WFF1 (Structure Protection for Wildland Firefighters), and S-215 (Fire Operations in the WUI), ensuring every deployment meets provincial and national standards.
Type 1 and Type 2 SPUs
Structure protection units are classified by capacity. A Type 2 SPU is designed to protect approximately 35 structures, making it well suited for smaller subdivisions, rural clusters, and isolated critical infrastructure. A Type 1 SPU scales significantly, capable of defending approximately 125 structures in larger community protection scenarios. Baumanis maintains both types, selecting and configuring the right package based on the threat assessment and community layout.
The Humidity Bubble Concept
The core principle behind structure protection is the creation of a humidity bubble — a localized zone of elevated moisture surrounding a structure. Sprinkler systems, misting arrays, and hose lay networks saturate roofs, walls, decking, and surrounding vegetation. This sustained wetting suppresses ignition potential even as the fire front passes through, buying critical time for structures to survive the peak heat exposure.
Five-Phase Deployment Framework
Baumanis follows a disciplined five-phase approach to every structure protection deployment:
- Threat Identification — Assessing fire behaviour, weather forecasts, fuel types, and approach vectors to determine which structures are at risk and the timeline for potential impact.
- Triage — Prioritizing structures based on defensibility, construction materials, surrounding fuel loads, and available water supply. Not every structure can be defended — triage ensures resources go where they will be most effective.
- Deploy — Setting up SPU equipment including sprinklers, hose lays, portable pumps, and water supply infrastructure. Crews create defensible space by clearing combustible materials within the immediate zone around each structure.
- Operate — Activating and monitoring systems through the fire front passage. SPC personnel manage water flow, adjust coverage, troubleshoot equipment, and make real-time decisions as conditions change.
- Post-Front — After the fire front passes, crews patrol for spot fires, smouldering debris, and structural ignitions. Equipment is demobilized and structures are assessed for damage.
Defensible Space and WUI Expertise
Effective structure protection starts well before the fire arrives. Baumanis crews create defensible space around threatened structures by removing ladder fuels, clearing gutters and decking of debris, relocating combustible materials, and establishing fuel-free zones. Our experience operating in the Wildland-Urban Interface means we understand the unique challenges where forest fuels meet residential construction — from cedar shake roofs to wooden fences that act as fire wicks.
High-Volume Water Delivery
Structure protection operations demand sustained, high-volume water delivery. Baumanis provides water tenders, portable pump systems, and hose lay infrastructure capable of supplying SPU operations for extended periods. Our logistics team coordinates water sourcing, shuttle operations, and supply line maintenance to ensure uninterrupted flow throughout the deployment.
Certifications & Standards
All Baumanis structure protection personnel hold current WSPP-115, SPP-WFF1, and S-215 certifications. Our contract crews operate under provincial coordination frameworks and integrate seamlessly with BC Wildfire Service incident command structures. Baumanis has been SAFE certified through the BC Forest Safety Council since 2012.