Subcomponents & Engineered Wood Products
Subcomponents are parts of the structure framing process, but are not a full roof truss, wall panel, or floor truss. They are products that are traditionally constructed on the jobsite, but rather are mass produced by a component manufacturer to create efficiencies for builders, framers, and general contractors.
- Pre-cut Headers: Structural member located between stud, joist, rafter, or truss openings.
- Window Openings: Rough opening in a wall panel where the window will be installed as the house is constructed. Some component manufacturers install the windows in their plant during manufacturing.
- Door Openings: Rough opening in a wall panel where the door will be installed as the house is constructed. Some component manufacturers install the doors in their plant during manufacturing. Used instead of wall panels – frame around it.
- Trimmers/Jacks: Conventionally framed wall usually consisting of fastened multiple studs in a framed wall opening, used to carry the header reactions
- Shear Blocking: plywood nailed to short wall studs that help prevent a wall from sliding or collapsing.
- Ladder Panel: Prefabricated panel fastened to the roof eave to create a sloped overhang.
Engineered Wood Products
Engineered wood, also called composite wood, man-made wood, or manufactured board, includes a range of derivative wood products which are manufactured by binding or fixing the strands, particles, fibers, or veneers or boards of wood, together with adhesives, or other methods of fixation to form composite materials.
- I-joist: Structural member manufactured using sawn or structural composite lumber flanges and structural panel webs, banded together with exterior exposure adhesives, forming the cross-section shape of the capital letter "I". These members are primarily used as joists in floor and roof construction.
- Structural Composite Lumber (SCL): Composite of wood veneer sheets, elements, or wood strand elements, joined with an adhesive with wood fibers primarily oriented along the length of the member. These materials are intended for structural use. Examples included LVL and PSL.
- Laminated Veneer Lumber (LVL): Composite of wood veneer sheet elements joined with an adhesive with wood fibers primarily oriented along the length of the member. Veneer thickness does not exceed 0.25".
- Parallel Strand Lumber (PSL): Composite of wood strand elements joined using an adhesive with wood fibers primarily that are oriented along the length of the member. The least dimension of the strands shall not exceed 0.25", and the average length shall be a minimum of 150 times the least dimension.
- Laminated Strand Lumber (LSL): Laminated strand lumber is a structural member made by cutting long thin strands directly from de-barked logs. The strands are blended, coated with adhesive and oriented so that they are essentially parallel to the longitudinal axis of the section before being reformed by steam-injection pressing into a solid section. LSL is used in similar applications to LVL.
- Glued Laminated Timber (Glulam): A structural member made by gluing together a number of graded timber laminations with their grain parallel to the longitudinal axis of the section. Members can be straight or curved, horizontally or vertically laminated and can be used to create a variety of structural forms.
- Cross Laminated Timber (CLT): A structural timber product with a minimum of three cross-bonded layers of timber, and glued together in a press which applies pressure over the entire surface area of the panel. CLT panels typically have an odd number of layers (3,5,7,9) which may be of differing thicknesses but which are arranged symmetrically around the middle layer with adjacent layers having their grain direction at right angles to one another.
- Nail Laminated Timber (NLT): A mass timber panel system which can be used for floor, wall, and roof structures and is created from dimensional lumber stacked fastened together with nails. Plywood sheathing is often added to one top side to provide a structural diaphragm.
- Mass Plywood Panel: Veneer-based composite lumber panel designed to be an alternative to CLT.
- Finger-jointed Lumber (FJL): dimensional lumber where fingers are cut into the ends of the pieces before they are glued together.