Code of Massachusetts Regulations › 780 CMR - STATE BOARD OF BUILDING REGULATIONS AND STANDARDS › Chapter 23 - Wood › Section 2302 - DEFINITIONS › Subsection 2302.1 - Definitions

Current through Register 1525, July 5, 2024
The following words and terms shall, for the purposes of
				  this chapter, have the meanings shown herein.
ACCREDITATION BODY.
An
approved
, third-party organization that is independent of the
				  grading and inspection agencies, and the lumber mills, and that initially
				  accredits and subsequently monitors, on a continuing basis, the competency and
				  performance of a grading or inspection agency related to carrying out specific
				  tasks.
BRACED WALL LINE.
A series of braced wall panels
				  in a single
story
that meets the requirements of Section
				  2308.3 or 2308.12.4.
BRACED WALL PANEL.
A section of wall braced in
				  accordance with Section 2308.9.3 or 2308.12.4.
COLLECTOR.
A horizontal diaphragm element
				  parallel and in line with the applied force that collects and transfers
				  diaphragm shear forces to the vertical elements of the lateral-force-resisting
				  system and/or distributes forces within the diaphragm.
CONVENTIONAL LIGHT-FRAME CONSTRUCTION.
A type of
				  construction whose primary structural elements are formed by a system of
				  repetitive wood-framing members. See Section 2308 for
conventional
				  light-frame construction
provisions.
CRIPPLE WALL.
A framed stud wall extending from
				  the top of the foundation to the underside of floor framing for the lowest
				  occupied floor level.
DIAPHRAGM, UNBLOCKED.
A diaphragm that has edge
				  nailing at supporting members only. Blocking between supporting structural
				  members at panel edges is not included. Diaphragm panels are field nailed to
				  supporting members.
DRAG STRUT.
See "Collector."
FIBERBOARD.
A fibrous, homogeneous panel made
				  from lignocellulosic fibers (usually wood or cane) and having a density of less
				  than 31 pounds per cubic foot (pcf) (497 kg/m3) but
				  more than 10 pcf (160 kg/m3).
GLUED BUILT-UP MEMBER.
A structural element, the
				  section of which is composed of built-up lumber, wood structural panels or wood
				  structural panels in combination with lumber, all parts bonded together with
				  structural adhesives.
GRADE (LUMBER).
The classification of lumber in
				  regard to strength and utility in accordance with American Softwood Lumber
				  Standard DOC PS 20 and the grading rules of an
approved
lumber
				  rules-writing agency.
HARDBOARD.
A fibrous-felted, homogeneous panel
				  made from lignocellulosic fibers consolidated under heat and pressure in a hot
				  press to a density not less than 31 pcf (497
				  kg/m3).
NAILING, BOUNDARY.
A special nailing pattern
				  required by design at the boundaries of diaphragms.
NAILING, EDGE.
A special nailing pattern
				  required by design at the edges of each panel within the assembly of a
				  diaphragm or shear wall.
NAILING, FIELD.
Nailing required between the
				  sheathing panels and framing members at locations other than boundary nailing
				  and edge nailing.
NATURALLY DURABLE WOOD.
The heartwood of the
				  following species with the exception that an occasional piece with corner
				  sapwood is permitted if 90 percent or more of the width of each side on which
				  it occurs is heartwood.
Decay resistant.
Redwood, cedar, black locust
				  and black walnut.
Termite resistant.
Redwood, Alaska yellow-cedar,
				  Eastern red cedar and both heartwood and all sapwood of Western red
				  cedar.
NOMINAL SIZE (LUMBER).
The commercial size
				  designation of width and depth, in standard sawn lumber and glued-laminated
				  lumber grades; somewhat larger than the standard net size of dressed lumber, in
				  accordance with DOC PS 20 for sawn lumber and with the AF & PA NDS for
				  glued-laminated lumber.
PARTICLEBOARD.
A generic term for a panel
				  primarily composed of cellulosic materials (usually wood), generally in the
				  form of discrete pieces or particles, as distinguished from fibers. The
				  cellulosic material is combined with synthetic resin or other suitable bonding
				  system by a process in which the interparticle bond is created by the bonding
				  system under heat and pressure.
PREFABRICATED WOOD I-JOIST.
Structural member
				  manufactured using sawn or structural composite lumber flanges and wood
				  structural panel webs bonded together with exterior exposure adhesives, which
				  forms an "I" cross-sectional shape.
SHEAR WALL.
A wall designed to resist lateral
				  forces parallel to the plane of a wall.
Shear wall, perforated.
A wood structural panel
				  sheathed wall with openings, that has not been specifically designed and
				  detailed for force transfer around openings.
Shear wall segment, perforated.
A section of
				  shear wall with full-height sheathing that meets the height-to-width ratio
				  limits of Section 4.3.4 of AF & PA SDPWS.
STRUCTURAL COMPOSITE LUMBER.
Structural member
				  manufactured using wood elements bonded together with exterior adhesives.
				  Examples of structural composite lumber are:
Laminated veneer lumber (LVL).
A composite of
				  wood veneer sheet elements with wood fibers primarily oriented along the length
				  of the member.
Parallel strand lumber (PSL).
A composite of
				  wood strand elements with wood fibers primarily oriented along the length of
				  the member.
STRUCTURAL GLUED-LAMINATED TIMBER.
An
				  engineered, stress-rated product of a timber laminating plant, comprised of
				  assemblies of specially selected and prepared wood laminations in which the
				  grain of all laminations is approximately parallel longitudinally and the
				  laminations are bonded with adhesives.
SUBDIAPHRAGM.
A portion of a larger wood
				  diaphragm designed to anchor and transfer local forces to primary diaphragm
				  struts and the main diaphragm.
TIE-DOWN (HOLD-DOWN).
A device used to resist
				  uplift of the chords of shear walls.
TREATED WOOD.
Wood and wood-based materials that
				  use vacuum-pressure impregnation processes to enhance fire retardant or
				  preservative properties.
Fire-retardant-treated wood.
Pressure-treated
				  lumber and plywood that exhibit reduced surface-burning characteristics and
				  resist propagation of fire.
Preservative-treated wood.
Pressure-treated wood
				  products that exhibit reduced susceptibility to damage by fungi, insects or
				  marine borers.
WOOD SHEAR PANEL.
A wood floor, roof or wall
				  component sheathed to act as a shear wall or diaphragm.
WOOD STRUCTURAL PANEL.
A panel manufactured from
				  veneers, wood strands or wafers or a combination of veneer and wood strands or
				  wafers bonded together with waterproof synthetic resins or other suitable
				  bonding systems. Examples of wood structural panels are:
Composite panels.
A wood structural panel that
				  is comprised of wood veneer and reconstituted wood-based material and bonded
				  together with waterproof adhesive;
Oriented strand board (OSB).
A mat-formed wood
				  structural panel comprised of thin rectangular wood strands arranged in
				  cross-aligned layers with surface layers normally arranged in the long panel
				  direction and bonded with waterproof adhesive; or
Plywood.
A wood structural panel comprised of
				  plies of wood veneer arranged in cross-aligned layers. The plies are bonded
				  with waterproof adhesive that cures on application of heat and
				  pressure.