Coating Six Timber-Lagging Walls, 7,150 Square Feet, in South Sequoia National Park

Six walls, 7,150 square feet, one fire-scarred stretch of road. Partnering with MCM Construction, NanoTech coated six timber-lagging walls near Porterville with Wildfire Shield, holding the same Class A protection across every surface.

In August 2024, NanoTech Materials worked with MCM Construction to coat six wood timber-lagging walls in South Sequoia National Park near Porterville, California. Together they covered 7,150 square feet. The walls varied in size and shape, so the job came down to coordination: keep the application uniform across very different surfaces and reinforce the park's roadside infrastructure with one durable, fire-resistant barrier.

It was a large, high-profile job in a sensitive place, and it showed that Wildfire Shield holds up at scale.

Project at a glance

A large, multi-wall corridor in fire-scarred sequoia country

The job ran across six separate walls, from 350 square feet up to 3,000, along roads serving South Sequoia National Park near Porterville. The southern Sierra Nevada has lost giant sequoias to recent megafires, and the roadside wooden infrastructure that carries access to the groves is right in the path of that risk.

Consistency at scale

Coating 7,150 square feet across six different walls meant holding uniform dry-film thickness and reliable adhesion on every surface. At that scale, and in a setting that sensitive, repeatable quality control was the whole game.

How the coating protects wooden infrastructure

Wood ignites and chars under radiant heat and flame, then spreads fire and loses strength. Intumescent products only react once the wood starts to heat, which lets ignition beat activation and produces char that can smoke and off-gas.

A passive barrier that needs no activation energy

Wildfire Shield works passively from the moment it cures. Its patented ICP technology pairs high emissivity, high reflectivity and low thermal conductivity into a high-temperature thermal barrier with no flame spread and no smoke (ASTM E84 Class A, 0/0). In testing witnessed by Department of Transportation personnel, coated timber lagging was held under a direct propane-torch flame for 20 minutes while the thermocouples behind the coating stayed near ambient.

Wildfire Shield applied across six walls

Working with MCM Construction, NanoTech-guided crews sequenced and coated all six walls. They cleaned and moisture-checked each substrate and built Wildfire Shield up in passes to a uniform specified thickness. Careful coordination kept the finish consistent from the smallest wall to the largest.

What the coating system delivered

•     7,150 sq ft of Class A coated timber lagging across six walls (ASTM E84, 0/0)

•     Uniform dry-film thickness and adhesion across diverse surfaces

•     Passive, non-sacrificial protection with no activation energy

•     Existing timber preserved, with no large-scale concrete replacement

•     A water-based coating suited to a national-park setting

•     Backed by NanoTech's 10-year material warranty

Up to 3,637 giant sequoias were lost in recent fires, an estimated 3 to 5% of the world's population.

Multiple major fires in the last five years have directly hit infrastructure near Porterville, according to Axios, CAL FIRE and the NPS. The roads that serve the sequoia groves face that same wildfire exposure.

Proof that Wildfire Shield scales

Six walls and 7,150 square feet of roadside timber lagging now carry the same Class A passive fire protection, finished efficiently in a high-profile, sensitive location.

Porterville is the proof point for scale: many walls, many surface types, one consistent result, and a workable model for protecting large stretches of roadside infrastructure in fire-scarred country.

What this means for your team

The same outcome reads differently depending on your role. Here is what this project means for the people who own, specify and apply fire-protection coatings.

For DOT structural & fire-protection engineers

Wildfire Shield gives specifiers a documented, independently tested alternative to defaulting to concrete for fire-exposed wooden infrastructure. It is verified to ASTM E84 (Class A, 0/0), plus E119, E162 and E662, and it came through a 20-minute direct flame-impingement test on timber lagging witnessed by Department of Transportation personnel. That is the kind of evidence it takes to qualify a non-traditional material with confidence.

For DOT district managers & budget authorities

Coating in place, or shop-applying off-site, preserves existing timber lagging instead of replacing it with costlier concrete or steel. Wildfire Shield is non-sacrificial and is built to protect the structure across repeated fire events when the system is maintained, so it stretches mitigation budgets across more lane-miles while keeping crews and traffic moving.

For bridge & highway contractors / applicators

Wildfire Shield is sprayed or rolled with common equipment and conforms to the geometry of timber lagging, abutments and fences, with no jacketing or fabrication required. On-site or off-site shop application removes seasonal and just-in-time bottlenecks, and NanoTech's certified-applicator training and supervision keep DOT-specified work on schedule.

Wildfire Shield technical specifications

Wildfire Shield is a water-based, non-sacrificial fire-mitigation coating built on NanoTech's patented Insulative Ceramic Particle (ICP) technology. Key published properties are summarized below; confirm project specifics against the current Technical Data Sheet and SDS.

Frequently asked questions

Can Wildfire Shield handle large, multi-wall projects?

Yes. Porterville covered 7,150 square feet across six walls. For large or time-sensitive scopes, timber lagging can also be shop-applied off-site and delivered ready to install.

How is Wildfire Shield different from intumescent fireproofing?

Intumescent coatings have to be triggered by fire. They char and swell only after the substrate begins to heat, so the wood can ignite before the coating activates, and the char can give off smoke and toxicity. Wildfire Shield is non-sacrificial and works the moment it is applied. Its mix of high emissivity, high reflectivity and low thermal conductivity reflects and re-radiates heat and slows the heat that reaches the wood, with no flame spread and no smoke development (ASTM E84 Class A, 0/0).

Can the coating survive more than one fire?

Yes. Because it is non-sacrificial, Wildfire Shield is designed to protect the underlying structure through repeated wildfire events when the coating system is inspected and maintained. NanoTech recommends yearly inspections for wear, cracking or damage, and worn areas can be touched up by overcoating rather than fully replaced.

How hot can Wildfire Shield withstand?

It withstands direct flame exposure up to 3,272°F (1,800°C). In testing witnessed by Department of Transportation personnel, coated timber lagging was held under a direct propane-torch flame for 20 minutes while the thermocouples behind the coating stayed near ambient.

Is it safe and environmentally responsible?

Wildfire Shield is water-based and non-toxic, with no reportable VOCs and no toxic runoff or leaching, and it is not classified as hazardous for supply or use. It cleans up with water and suits sensitive settings such as national parks and the wildland-urban interface.

Related resources

From NanoTech Materials

•     Wildfire Shield product page

•     Fire Protective Coating System overview

•     Wildfire mitigation applications

•     Industries we serve

•     Resource library and case studies

•     Request a quote or join the certified-applicator network

External references

•     National Park Service: Sequoia & Kings Canyon

•     CAL FIRE (California Department of Forestry and Fire Protection)

•     ASTM International fire-test standards

Talk to NanoTech about wildfire protection

Protecting timber lagging, bridges, utility poles, fences or homes in a wildfire-prone area? Talk to NanoTech about Wildfire Shield, or join our certified-applicator network. Call (888) 296-6266, email [email protected], or visit nanotechmaterials.com.

About NanoTech Materials. NanoTech Materials is a Houston-based materials-science company developing advanced coatings for energy efficiency and fire protection. Its Fire Protective Coating System, including Wildfire Shield, is built on patented Insulative Ceramic Particle (ICP) technology to protect critical wooden infrastructure and high-value assets from wildfire, buying time and saving lives.

_{© 2026 NanoTech Materials. All rights reserved. Performance data summarized from NanoTech technical documentation (TDS, SDS, Application & Technical Manual) and the Wildfire Shield Project Portfolio; confirm project-specific details and current published values with a NanoTech representative.}