| Term |
Description |
| Tied
arch |
An
arch tied at the base with a tension member. |
| Tier |
horizontal
course in a unit of lumber. |
| Timber |
A
general term for natural or sawn wood in a form suitable
for building or structural purposes. |
| Timbers |
Lumber
5Ó or more in thickness. |
| Timbers |
Lumber
5" or more in thickness. |
| Tongue
and Groove |
A
joinery method where one board is cut with a protruding
"groove" and a matching piece is cut with a matching
groove along its edge. |
| Tongue
and groove joint |
A
joint where a ridge or tongue in one piece fits a matching
groove in the other. |
| Torque |
The
amount of force that is needed to turn an object such
as a screw or bolt. |
| Toughness |
A
quality of wood which permits the material to absorb
a relatively large amount of energy, to withstand repeated
shocks, and to undergo considerable deformation before
breaking. Specific toughness classification are set out
in AS 1720.2 SAA Timber Structures Code - Part 2 Timber
Properties. |
| Toughness |
A
property of wood that enables it to absorb a relatively
large amount of energy, to withstand repeated shocks,
and to undergo considerable deformation before breaking.
Trim The finish materials in a building, such as moldings,
applied around openings, e.g., window trim, door trim,
etc., or at the floor and ceiling of rooms, e.g., baseboard,
cornice, etc. |
| Trade
names |
the
accepted regional names given to particular species by
industry. Trade names are standardised in AS 2543, Nomenclature
of Australian Timbers and AS 1148, Nomenclature of Commercial
Timbers imported into Australia. |
| Transverse |
Across.
A transverse section is a section across the length of
a building or room. |
| Tread |
The
horizontal platform of a stair. |
| Trimmer |
The
structural member on the side of a framed rough opening
to narrow or stiffen the opening. Also the shortened
stud (jack stud) which supports a header in a door or
window opening. |
| Trimmer |
Square-edged
boards must pass in a transverse or sideways direction
through a battery of saws that precisely end-trim (PET)
the lumber to prescribed lengths. |
| Truss |
A
frame of members in the same plane joined only at their
end and all interconnected to form triangles. Primary
stresses are axial so that if loads are applied at the
joints, the stress in each member is in the direction
of its length. |
| Trussed
beam |
A
timber beam reinforced with a trussed metal tension rod. |
| Twist |
A
spiral distortion along the length of a piece of timber. |
| Twist |
A
defect referring to a deviation, flatwise, in a piece
of lumber, creating the form of a curl or a spiral. |
| Twist |
Warping
in lumber where the ends twist in opposite directions.
(Like twisting a towel) |
| Tyloses |
Extensions
of parenchyma cells, appearing somewhat like froth, into
the pores or vesels of some hardwoods, especially oak
and black locust, before or during heartwood formation.
Tyloses tend to prevent or greatly impede moisture movement
through the pores. |
| Underlayment |
A
layer of plywood or other manufactured board used as
a base material under finished flooring. Underlayment
is often used as a substrate to increase the strength
and/or smoothness of the flooring. |
| Understorey |
That
portion of the trees or other vegetation in a forest
stand below the main canopy level. |
| Unseasoned
timber |
Timber
in which the average moisture content exceeds 25 %. |
| Urban
wood |
Used
pallets, wooden shipping crates and clean construction
wood diverted from the waste stream and chipped for use
in making particleboard and MDF. |
| Veneer |
A
thin layer or sheet of wood. |
| Veneer |
A
thin sheet of wood cut from a log. |
| Veneer |
Thin
sheet of wood sliced, sawed, or rotary-cut from a log
or a flitch; Rotary-cut Veneer-Veneer cut in a lathe
which rotates a log or bolt, chucked in the center, against
a knifel Sawed Veneer-Veneer produced by sawing; Sliced
Veneer-Veneer that is sliced off a log, bolt, or flitch
with a knife. |
| Veneer
Logs |
Although
veneer logs are sold by the board foot, they are never
converted to lumber. Veneer logs are turned and rotary
cut, that is, the wood is peeled off the log by turning
it against a stationary knife. The sheets of wood may
be laminated into plywood or laminated veneer lumber
(LVL) products. |
| Veneer
Sheets |
Thin
sheets of wood of a specified thickness that are peeled,
sliced, or sawn from logs for use in plywood, paneling,
and furniture. |
| Veneer-core
Plywood |
Plywood
made from three or more pieces of veneer glued up in
alternating grain patterns. |
| Veneering |
Facing
a substrate with a thin layer of ornamental wood. |
| Vertical
integration |
In
the forest products industry, a vertically integrated
company grows its own trees, makes products from them,
then makes other products from fiber leftovers from the
initial manufacturing operation, then converts and adds
value to all these products. |
| Vertically
laminated timber |
Laminated
timber designed to resist bending loads applied parallel
to the wide face of the laminations. For vertical loads,
this means that the wide face runs vertically. |
| Vessels |
Relatively
large diameter hardwood cells that have open ends and
are arranged one above the other to form a continuous
tube. The openings of the vessels on the surface of a
piece of wood are usually referred to as pores. |
| Wane |
A
lumber defect referring to the absence of wood or the
presence of bark along an edge or corner. |
| Wane |
The
absence of wood on any face or edge of a piece of timber,
leaving exposed the original underbark surface with or
without bark. |
| Wane |
A
lumber defect referring to the absence of wood or the
presence of bark along an edge or corner. |
| Want |
The
absence of wood, other than wane, from the arris or surface
of a piece of timber. |
| Warp |
A
lumber defect referring to any combination of bow, crook,
cup, or twist. |
| Warp |
Any
variation from a true and plane surface. It includes
bow, cup and twist and is often caused by irregular seasoning. |
| Warp |
A
defect in lumber characterized by a bending in one or
more directions. |
| Warp |
A
lumber defect referring to any combination of bow, crook,
cut, or twist. |
| Water
repellent |
A
liquid that penetrates wood which, after drying, materially
retards changes in moisture content and in dimensions
without adversely altering thedesirable properties of
wood. |
| Water-repellent
preservative |
A
water repellent that contains a preservative which, after
application to wood and drying, accomplishes the dual
purpose of imparting resistance to attack by fungi or
insects and also retards changes in moisture content. |
| Wavy
figure |
Markings
in the form of waves or undulations. Figures with large
undulations are described as 'wavy', while others with
small, irregular undulations are 'curly', and those with
small, regular undulations are 'fiddleback'. |
| Weatherboard |
Boards
that cover external surfaces and overlap to keep out
the rain. |
| Weathering |
The
mechanical or chemical disintegration and discoloration
of the surface of wood caused by exposure to light, the
action of dust and sand carried by winds, and the alternate
shrinking and swelling of the surface fibres with the
variation in moisture content. Weathering does not include
decay. |
| Weathering |
The
cumulative effect of surface deterioration in wood exposed
to the weather and unprotected by paint or other means.
It is also the mechanical and chemical disintegration
and discoloration of wood surface caused by exposure
to light, dust and sand carried by winds. It does not
include decay. |
| Web |
Any
transverse lateral stiffener. |
| Weekly
pricing guides |
Reports
published weekly by independent companies charting the
prices of many common lumber items. |
| Wetwood |
Green
wood with an abnormally high moisture content that generally
results from infections in living trees by anaerobic
bacteria, but may also result from water logging during
log ponding. The condition can occur in both softwoods
and hardwoods; the green lumber is usually difficult
to dry without defects. Although difficult to recognize,
wetwood is often characterized by a translucent, watersoaked
appearance and a sour or rancid odor. |
| White
lumber |
Lumber
that has not been treated. |
| Whole
tree chips (WTC) |
Some
mechanized loggers reduce trees that are not otherwise
marketable as logs to whole tree chips to be sold to
wood energy plants. Whole tree chips differ from mill
chips in that they include the bark, sapwood, and heartwood
of the tree, as well as branches and leaves (from deciduous
or hardwood trees) or needles (from evergreen or softwood
trees). |
| Wholesaler |
One
who purchases material from a producer or remanufacturer,
for resale to retailers, industrial users, etc., While
also providing for transportation, credit, and other
services. |
| Wild
figure |
Irregular
markings. |
| Wind
bracing |
Bracing
members required to resist the forces on a structure
resulting from wind pressure. |
| Wind
post |
A
column that stiffens a framed wall against wind loads. |
| Wood |
The
hard compact fibrous substance of which trees and shrubs
are largely composed. |
| Wood
Biodeterioration |
The
destruction and eventual reduction of wood to its component
sugars and lignin elements through attack by organisms
such as, fungi, and certain insects, for instance, termites.
Blue Stain
A bluish or DimGrayish discoloration of the sapwood caused
by the growth of certain dark-colored fungi on the surface
and in the interior of the wood, made possible by the
same conditions that favor the growth of other fungi.
Also known as sap stain or sapwood stain.
Brown Rot
Any decay in wood in which the attack is confined to
the cellulose and associated carbohydrates rather than
the lignin, producing a light to dark brown friable residue
- hence the term "dry rot". An advanced stage of brown
rot where the wood splits along rectangular planes, in
shrinking, is referred to as "cubical rot."
Dry Rot
A term loosely applied to any dry, crumbly rot but especially
to that which, when in advanced stage, permits the wood
to be crushed easily to dry powder.
Marine Borers
Mullosks and crustaceans which attack submerged wood
in salt and brackish water.
Powder-Post Damage
Small holes (1/16" to 1/12" in diameter) filled with
dry, crumbled wood, resulting from the work of beetles
(mostly Lyctus) in seasoned and unseasoned wood.
Soft Rot
A special type of decay that develops in the outer wood
layers under very wet conditions, such as in cooling
towers and boat timbers. It is caused by microfungi that
attack the secondary cell walls (and not the intercellular
layer) and destroy its cellulose content.
White Rot
A type of wood-destroying fungus that attacks both cellulose
and lignin, producing a spongy and stringy mass that
is usually whitish but which may assume various shades
of yellow, tan, and light brown. |
| Wood
energy plants |
Electric
generating plants that burn wood chips as fuel to produce
steam and electricity. A number of these plants were
built in the 1970's subsidized by the federal government
and electric utilities when the price of foreign oil
rose dramatically. |
| Wood
Preservation |
The
introduction of preservatives into wood to protect it
from agents of destruction and bio-deterioration, such
as fire, insects, and fungi. |
| Work
to Maximum Load |
In
bending, it represents the ability of wood (or other
materials) to absorb shock with some permanent deformation
and more or less injury to the piece. It is a measure
of the combined strength and toughness of wood under
bending stresses. |
| Workability |
The
degree of ease and smoothness of cut obtainable with
hand or machine tools. |
| Working
Life (Pot Life) |
The
amount of time after mixing that a glue or paint remains
usable. Often used when referring to two-part epoxy and
polyester glues. |
| Wormholes |
Holes
and channels cut in wood by insects. |
| X |
The
drafting symbol for a cross section of an object. |
| Xylem |
The
cellular tissue inside a tree's bark often called wood.Ê |
| Yield |
The
proportion of the log converted
into lumber is the product
that produces the greatest
value. The percentage of
the log that winds up in
as lumber (54-55%), sawdust
(4-19%), or chips (27-41%)
depends upon: 1) Thickness
of lumber being cut; 2) Skill
of the sawyer; 3) Type of
headsaw; 4) Saw kerf; 5)
Losses in edging, trimming,
drying, and surfacing |
