Treated to help inhibit mold on the lumber surface, and to resist fungal decay and wood-destroying insects, including Formosan termites. Adds ASTM E84 surface-burning performance on listed lumber where fire-retardant-treated wood is not required.
A practical step up when surface-burning performance matters.
3300 occupies a very specific place in the RezWood™ family: it adds tested surface-burning performance to RezWood-treated lumber when a project wants a stronger fire story, but the applicable code does not require fire-retardant-treated wood.
Explore 3300
The details that matter.
Applications, protection, certifications and warranty options for 3300. Each section opens on this page.
Added fire performance—without confusing it with FRTW.
Blue-identifiable dimensional framing that combines mold, decay, and subterranean-termite protection with ASTM E84-tested surface-burning performance for projects that do not require code-defined FRT lumber.
01
Read the rating by substrate
In the current third-party evaluation, treated dimensional SPF, Douglas fir, and Southern pine achieve Class A surface-burning classifications. Several evaluated engineered substrates are Class B, so the classification must follow the exact substrate specified. Request the Report through TechWood’s controlled technical-document process.
02
Use 3300 for the right reason
3300 is intended for conditions where FRT lumber is not required by code but Class A or Class B ASTM E84 surface-burning performance is desired. Where FRTW is required, specify 4400 instead.
03
Protect it from direct wetting
3300 is suitable for above-ground applications not exposed to liquid water. Protected exterior applications require the coating, flashing, and finish details described in the current report.
Common applications
Residential dimensional framing packagesInterior wall framingJoists and raftersStuds, plates, and sill platesOther qualifying framing where FRTW is not requiredProjects requesting added E84 surface-burning performance
What we protect againstProduct-specific protection
Protection built into 3300.
The protection below applies to the treated lumber—not every material in the building—and only within the selected product's documented scope.
01
Mold-growth inhibition
Helps inhibit mold growth on the treated lumber. Moisture management, drying, and jobsite housekeeping still matter. The public technical evaluation documents mold-growth-inhibition testing using ASTM D3273 and ASTM D5590 methods.
Resists decay fungi within the documented exposure conditions. It does not replace flashing, drainage, ventilation, or maintenance. The public technical evaluation documents fungal-decay resistance for the approved lumber, application, and above-ground exposure scope.
Subterranean-termite resistance, including Formosan termites
Resists subterranean termites, including Formosan termites, within the current product scope. Untreated wood and cellulose remain outside the protection package. The public technical evaluation documents subterranean-termite resistance for eligible treated lumber within the approved application and exposure scope.
ASTM E84 classification is substrate-specific; dimensional SPF, DF, and SYP achieve Class A values in the current report The documented surface-burning classification follows the exact treated substrate and is not a substitute for fire-retardant-treated wood where FRTW is required.
Ordinary preservative-treated lumber is not automatically fire-retardant-treated wood. RezWood 3300 combines its preservative package with documented ASTM E84 surface-burning performance for projects that want that added performance but do not require code-defined FRTW.
TestingCertifications + fit
Public technical record
Testing behind the treatment.
Review the standards, certifications and application limits for the selected lumber and project.
01
GREENGUARD Certified for low emissions
The supplied certification covers the finished 3300 system tested with wood under UL 2818 for low chemical emissions.
02
ASTM E84 surface-burning performance
Documented dimensional SPF, Douglas fir, and Southern pine achieve a Class A surface-burning classification. The classification must follow the exact substrate.
03
Third-party evaluated applications
Independent technical evaluation supports approved preservative and surface-burning applications under the documented building-code conditions.
04
Not a substitute for required FRTW
3300 adds documented surface-burning performance, but it is not represented as fire-retardant-treated wood. Where the code requires FRTW, specify an approved FRT system such as 4400.
Important context
Technical fit: UC1, UC2, and protected UC3A conditions. Texas Wood Tech currently offers RezWood™ 3300 in common dimensional lumber sizes. Engineered panels, large beams, and truss programs shown within the broader TechWood evaluation are not part of the current RezWood™ offering.
Codes and evaluation reportsTechnical clarity
Know exactly what you are specifying.
Current RezWood™ availability
Texas Wood Tech currently offers RezWood™ 3300 in common dimensional lumber sizes. Engineered panels, large beams, and truss programs shown within the broader TechWood evaluation are not part of the current RezWood™ offering.
Fire role: ASTM E84 classification is substrate-specific; dimensional SPF, DF, and SYP achieve Class A values in the current report. Exposure: UC1, UC2, and protected UC3A conditions.
Water-based, mineral-centered protection
Choose fasteners for the treatment, exposure, building code and connector manufacturer’s guidance. RezWood™ 3300 has supplied certification for a system tested with wood under UL 2818 for low chemical emissions.
Cutting any lumber creates wood dust. Use dust control, eye protection and job-specific PPE. Never burn treated wood; confirm local reuse and disposal requirements.
DocumentsReports and warranty text
The written record for TW3300.
Warranty terms, evaluation support, and protection topics stay on their existing pages. Figures in those documents are unchanged.
CTH will warrant the treatment of wood components delivered and stored at construction sites for (4) four months, subject to the treated wood being stored off the ground, covered in its protective cover and safeguarded from accumulation of snow or standing water or water runoff.
02
Vertical framing · Up to 6 months · Unprotected framed state
CTH warrants the treatment of wood components of a covered structure for up to six (6) months in an unprotected vertical framed state, subject to proper documentation indicating completion of structure exterior wrapping or dry-in process.
03
Cured film surface · 5 years · Mold
The CTH Wood Treated Component is warranted to inhibit mold fungus growth/mycotoxin production on the cured surface of the film for 5 years.
04
Covered interior structures · 10 years · Decay and wood-ingesting insects
The CTH Wood Treated Component is warranted against wood-rot fungi decay and wood ingesting insects (including subterranean or Formosan termites) or carpenter ants, due to the failure of CTH WoodSurfaceFilm™ treatment while owned for 10 years. Such failure must render the CTH Wood Treated Component incapable of performing its intended purpose.
Important context
The Warranty Period begins on the date of purchase. This warranty is extended to the first owner after the original builder/general contractor purchases the material and is non-transferrable. Written notice is required within thirty (30) days. Conditions and exclusions apply.
