Dricon® Fire Retardant Treated (FRT) wood is frequently used for roofing, framing, and flooring applications, impeding flame spread and smoke generation.
Dricon® FRT wood is ideal for use:
•Where other materials would permit a fire to spread without restriction
•In areas of construction where there is inadequate water supply or fire protection
•In indoor construction staging, scaffolds, workmen’s shanties, etc., during construction or repairs of equipment or multi-story buildings
•In health care facilities
•In homes located in areas prone to wildfires or anywhere fire safety is a concern
•As sill plate
•Mass transit vehicles
Dricon® FRT wood is frequently used in multi-family dwellings, schools, hospitals, office buildings, theaters, shopping centers, and wherever building codes require an extra measure of protection for occupants.
Homeowners and architects may select Dricon® FRT wood for all framing members or just for critical components. In what is known as a ‘complete application,’ architects use Dricon® FRT wood for trusses, roof sheathing, interior framing, sub-flooring, sill plates, nailers, etc. In a ‘partial application’ Dricon® FRT wood is used for stairway systems, chimney wraps, door and window casings, etc.
In some areas, the use of fire resistant materials in residential construction is now required by ICC’s International Urban-Wildland Interface Code. More and more homeowners are using Dricon® wood for increased safety. According to Home & Fire magazine, upwards of 12,000 communities in the U.S. are officially at risk from severe wildfire.
When steel studs are selected, Dricon® FRT underlayment and sheathing makes the entire framing package resistant to termites, decay, and flame spread.
Dricon® FRT wood is for use in above-ground locations, protected from precipitation, regular condensation, or other wetting. Dricon® can be used in contact with concrete that contacts the ground.
Tips On Use
•Dricon® FRT wood should be handled like any other wood product. Wear gloves to avoid splinters, use a dust mask and eye protection when using power tools, and wash your hands after working. Ingestion tests have demonstrated that extreme amounts of wood must be ingested before the chemical exposure would become significant. Tests have shown smoke from Dricon® FRT wood to be no more toxic than untreated wood.
•Dricon® FRT wood should not be installed where it will be exposed to precipitation, direct wetting, regular condensation, or come into direct contact with the ground.
•When storing Dricon® FRT wood, the material should be kept off the ground and covered to shield it from precipitation.
•Dricon® FRT plywood should be spaced and fastened as recommended in “APA Engineered Wood Construction Guide,” (Form 30) published by APA-The Engineered Wood Association.
•End cutting, drilling, joining, and light surface sanding will not significantly reduce the benefits of the Dricon® treatment. It is not necessary to field-treat cut ends to maintain flame spread rating.
•Ripping and milling are not permitted except on red oak and yellow poplar lumber. Surfacing to a depth of 1/16″ is permitted on western red cedar lumber.
•Dricon® FRT plywood can be cut in either direction without loss of fire protection.
•When painting or staining, the paint or stain manufacturer’s recommendations should be followed.
•Carbide-tipped saw blades are recommended if extensive cutting operations are to be performed, but Dricon® FRT wood is not as dulling as many conventional fire retardants.
•Do not burn any fire retardant treated wood.
Disposal
This product is typically not considered a hazardous waste under federal requirements, but state-run waste programs may be more stringent. Check with your local or state regulators prior to disposal.
Finishing
Stain, sealers, varnishes, and paints can be used with Dricon® FRT wood. Paint systems may be water or oil-based. Stains, especially dark-colored semi-transparent types, should be solvent-based to avoid possible surface crystallization of the fire retardant chemical. Flammability of finish should be considered prior to application. Follow manufacturer’s recommendations for finish application.
Gluing
The Dricon® treatment does not adversely affect the performance of nonstructural construction adhesives, mastics, or contact cements. Be sure the Dricon® wood surface is clean and dry to obtain best performance.
Fire Performance
Dricon® FRT wood has been tested for fire performance by several independent laboratories and meets model code requirements for a Class A/Class 1 fire retardant. As a result of tunnel testing (UL 723, ASTM E 84, ASTM E 2768 and NFPA 255 are essentially identical) an FR-S surface burning characteristic classification has been assigned to all softwood species of Dricon® FRT wood. For most wood species, Dricon® FRT wood has a flame spread and smoke developed index of 25 or less when tested in the E 84 tunnel test and shows no evidence of progressive combustion in 30 minutes. Dricon® treatment reduces the flame spread to less than 15 which is essentially the same as gypsum wallboard.
Factory Mutual Research has also evaluated Dricon® FRT wood and found that it meets their requirements for a Class 1 treated wood roof deck per the FMRC calorimeter.
The Hardwood Plywood Manufacturers Association conducted the ASTM E 162 radiant panel test and NFPA 258 smoke density test and have demonstrated the acceptability of Dricon® FRT wood under Department of Transportation regulations for use in mass transit vehicles.
Dricon® FRT wood has been tested in accordance with the following procedures:
•ASTM D 1413
•ASTM E 72
•NFPA 255
•ASTM D 3201
•ASTM E 84
ASTM E 2768
•NFPA 258
•ASTM D 3345
•ASTM E 162
•NFPA 259
•ASTM D 5516
•Boeing BSS 7239
•UL 723
•ASTM D 5664
•MIL-L-19140
Hourly Ratings
Dricon® fire retardant treated wood has a surface burning classification and, by itself, does not have a resistance rating in hours any greater than untreated wood. Fire ratings in hours are assigned to door, wall, or deck assemblies following testing in accordance with ASTM E 119 and E 136. Dricon® FRT wood can be used as a component of such assemblies in structures where the code does not permit the use of untreated wood.
One-Hour Wood Truss Assemblies
Dricon® FRT wood can be used in place of untreated wood in many wood truss designs and will enable the use of these assemblies in many building construction types that do not permit untreated wood. These construction assemblies provide significant savings when Dricon® wood construction is substituted for hourly rated steel or concrete construction.
Hygroscopicity
A material which gains moisture from the atmosphere as the relative humidity increases is said to be hygroscopic. Wood is naturally hygroscopic, and fire retardants can increase this property. Dricon® fire retardant was developed specifically to minimize the impact of hygroscopicity and corrosion.
The AWPA standards differentiate between “low-hygroscopic” Type A products and other more hygroscopic Type B products. Type A products are also differentiated by their intended application (i.e., Type A high temperature (HT) and Type A low temperature (LT). Dricon® FRT wood is listed as an interior Type A (HT) product by AWPA. In tests conducted in accordance with ASTM D 3201, there was very little difference between the moisture content of Dricon® FRT wood and untreated wood.