Fire Resistant Prefinished Wood Siding | Class A

Beautiful Class A Wood Siding

Montana Timber Products offers industry-leading flame retardant solutions ensuring compliance with stringent fire codes while preserving the beauty of prefinished natural wood. Whether you’re building in a wildfire-prone zone with strict requirements or seeking enhanced peace-of-mind fire protection, we have the solution for you.

Flame Retardant Treatment Options

	SaferWood Thermex-FR™ (Fireline)	FX LumberGuard XT
Fire Rating	Class-A (ASTM-E84 extended 30-minute test) – IBC 2303.2 Compliant	Class A (ASTM E84)
Classification	FRTW (Fire Retardant Treated Wood)	Fire Retardant Coating
Penetration	Pressure-impregnated entire substrate	Surface
WUI Compliance	Yes	No
Standards Met	Meets or exceeds IBC 2303.2, IWUIC, Cal-Fire BML #2520-1450:0502	Intertek CCRR-1044

Both treatments available across all of our prefinished products. Fire treatments are first applied to our lumber followed by our factory finish.

SaferWood Thermex-FR™ (Fireline): World-class FRTW

SaferWood Thermex-FR™ stands out as the superior choice for fire protection:

Advanced Fire Resistance: Exceeds WUI standards with a 30-minute ASTM E84 test, compared to the standard 10-minute test.
Permanent Protection: Pressure-impregnated treatment penetrates the entire substrate, ensuring lifetime durability.
Compliance Excellence: Fully meets IBC 2303.2 and IWUIC standards, making it ideal for high-risk wildfire zones.
Cal-Fire Approved: Listed under Cal-Fire Building Materials Listing #2520-1450:0502.

THERMEX-FR (FIRELINE) – 3rd Party Evaluation Report

FX LumberGuard XT: A Cost-Effective Option

FX LumberGuard XT is a spray-applied fire-resistant coating that provides Class A fire protection for projects where WUI compliance is not required. It is a great option for:

Faster turnaround times
Lower-cost
Great for interior applications

FX LumberGuard XT – 3rd Party Evaluation Report

FREE: Home Hardening Guide

We have put together a free home hardening checklist full of tips and best practices to help guide you through the process of hardening your home from the threat of wildfires.

Download Now

Interested in Learning More?

With over a decade of experience, we are experts in fire-retardant wood solutions that balance safety and aesthetics. Our knowledgeable sales team will help you navigate the changing landscape of wildfire safety and property insurance, providing personalized guidance on product compatibility, color selection and code compliance to ensure your project’s success.

Why Montana Timber Products?

natural wood

Embrace Authentic Beauty: We take pride in offering a stunning selection of sustainably farmed species, including Douglas Fir, Cedar, Southern Yellow Pine, and Hemlock ideal for architectural cladding and timbers. Elevate your space with the warmth and elegance of natural wood.

Custom milled

Tailored to Perfection: We can meet your exact design needs our product offerings range from custom siding and trim to large post and beam applications. MTP is the industry leader in specialty lumber.

prefinished

Ready for Immediate Use: Save on time and quality. Our durable, professional-grade Seal-Once finish, applied in our controlled facility, offers superior UV and water protection. Enjoy our premium finish options without the hassle of on-site finishing.

direct to customer

Simplified Purchasing Experience:  We streamline the buying process and eliminate unnecessary middlemen. This direct relationship ensures that your specific needs are met with efficiency and care. Delivered directly to your jobsite.

Fire Treatment Options FAQ

What fire treatment options does Montana Timber Products offer?

Montana Timber Products offers two fire treatment options: Thermex-FR (Fireline) pressure-impregnated and FX LumberGuard XT, a spray-applied fire-resistant penetrant.

How are these fire treatments applied?

The topically applied treatment is sprayed onto the wood in-house by Montana Timber Products. Thermex-FR (Fireline) is pressure-impregnated by their partner company.

What applications can these flame retardant options be used for?

Both flame retardant options can be applied to all prefinished materials provided by Montana Timber Products, including siding, soffit, fascia, trim, timbers, posts, beams, and decking.

How do these fire treatments affect the appearance of the wood?

Expect greater color variation with the both treatments. The tint color in our stains and its interaction with treated lumber are variable, often resulting in a more solid appearance compared to non-treated lumber. Customer approval of samples is strongly recommended.

Are these treatments environmentally friendly?

Yes, both treatments use safe, environmentally friendly additives and are non-toxic to the environment.

How long do the treatments last?

Both provide fire protection that lasts for the useful life of the wood product and never needs to be re-treated.

What's the difference between thermal modification and fire treatment?

Thermal modification is a process that alters the wood's properties to improve durability and stability, while fire treatment refers to a material's ability to resist ignition and slow the spread of fire. These are separate processes with different purposes.

Can thermally modified wood be fire treated?

While thermal modification alone doesn't inherently provide fire prevention, thermally modified wood can be fire treated. Montana Timber Products offers fire treatment options for both thermally modified and non-modified wood.

What tests has the Thermex-FR (Fireline) treatment passed?

Thermex-FR (Fireline) treatment has passed numerous rigorous tests, including:

ASTM E84 – 30-min test (modified by IBC Section 2303.2) for flame spread and smoke development
CAN/ULC-S102-10 for surface burning characteristics
ASTM D5516 for evaluating flexural properties of fire-retardant treated softwood plywood exposed to elevated temperatures
ASTM D5664 for evaluating effects of fire-retardant treatments on strength properties of wood
ASTM D6305 for effect of fire-retardant treatments on strength of structural-grade lumber
ASTM D6841 for calculating allowable properties for fire-retardant-treated lumber
Wildland Urban Interface (WUI) and International Wildland Urban Interface (I-WUI) standards
Extended surface burning tests
Weathering tests

What tests has FX LumberGuard XT fire treatment passed?

FX LumberGuard XT has passed numerous rigorous tests, including:

ASTM E84 Extended/ASTM E2768 standards, meeting 2024 IBC 2303.2.1 requirements.
ASTM E2768 for surface burning characteristics.
ASTM D3201 for hygroscopic properties.
ASTM D5516 for evaluating flexural properties of fire-retardant treated softwood plywood exposed to elevated temperatures.
ASTM D5664 for evaluating effects of fire-retardant treatments on strength properties.
NFPA 703/255, UBC42.1, ASTM E119, NFPA 259, ASTM D2369, CAN/ULC S102, and AWPA E121.
UL Greenguard Gold Certified for low VOCs (emissions and content).

Fire Resistant Options for Class A Wood Siding