HomeMy WebLinkAboutMiscellaneous - Exception (52)STRENGTH
FRX® wood has been tested in accordance with ASTM D 143 and MIL -L -19140E. Following are the design value adjustments.
Strength Design Factors for FRX° Fire Retardant
Treated Lumber Compared to Untreated Lumber
Applicable at Ambient Temperatures Up to 80' F*
Allowance Total Sheathing Load (psf)
for FRX® Plywood
Plywood
Thickness
(inch)
Tested Species
Southern Douglas
Pine Fir
Compression Parallel
1.00
1.00
Horizontal Shear
0.91
1.00
Tension Parallel
0.78
0.88
Bending: Modulus of Elasticity, E
1.00
0.96
Extreme Fiber Stress, Fb
1.00
1.00
Allowance Total Sheathing Load (psf)
for FRX® Plywood
Plywood
Thickness
(inch)
plywood
Rating
12
16
19.2
Span (inches)
24 30 32 36 40 48
5/16
20/0
185
104
67
47
3/8
24/0
280
161
103
71 28
15/32,1/2
32/16
409
231
145
102 65 57
19/32,5/8
40/20
641
361
231
160 103 88 57 46
23/32,3/4
48/24
805
453
290
202 128 114 71 61 41
*Lonza Wood Protection does not recommend the use of Table based on Structural 1, exterior -grade plywood. Fastener size and spacing must be as
FRX® wood in high temperature interior applications. Dricone required in the code for untreated plywood of the same thickness.
FRT wood should be used in these situations. Contact
Lonza Wood Protection or visit us online at www.dricon.com
for more information.
APPEARANCE
The treatment has little effect on the color of lumber. Deposits
of FRX° fire retardant solution may appear on the surface
of wood or exude from the edges of plywood during drying.
This is a result of injection of adequate chemical to achieve
desired fire protection, and is considered normal. On most
species, discoloration is barely noticeable.
Marks made by stickers, used to separate the layers of
lumber during the kiln drying following treatment, will be
noticeable on lumber. For structural use, this is not usually
objectionable. FRX® exterior FRT wood can be special ordered
with one face free of sticker marks. Slight irregular water
marks may show on such material.
The pressure treatment and subsequent drying may result
in a slight waviness in plywood; for normal applications this
is not a problem as the plywood can be straightened when
nailing.
TIPS ON USE
1. FRX® wood should not be installed where it will be
exposed to high interior temperatures, or in contact
with the ground.
2. When painting or staining, the paint or stain manufacturer's
recommendations should be followed. As with untreated
lumber, the surface should be clean and dry. See
www.frxwood.com for more details.
3. The same common sense precautions should be taken
when handling FRX® wood as with untreated wood or
other building materials. Dust masks and eye protection
devices are recommended to avoid possible irritation
from sawdust and wood chips. Gloves will help avoid
splinters. Hands should be washed after doing construction
work.
0 2012 Arch Wood Protection, Inc., a Lonza company FRX-2031-112