Air dried - To dry by exposure to the air.

Active solar - Uses mechanical devices to transfer collected heat from the sun to storage mediums and/or end use.

Bay - Space between two timber bents.

Beam - A horizontal member supporting either a roof, ceiling, or floor joist.

Beetle - A heavy wooden maul or mallet used in cases in which material would be damaged by a sledge hammer.

Bent - A structural section of the timber frame having principal rafters and principal posts connected in such a way to support roof and / or and floor loads.

Bent style - For our purpose, the bent style or design relates to the visual image of the timber components that form the bent.  The bent is the structural element where we can get "artistically creative."  Some common Style examples include: hammer beam, barrel vault, king post, queen post, scissors, etc.

Blueboard - Weather resistant, plaster-based drywall.

Boxed heart - A timber sawn so that the center part of the tree is centered at both ends of the timber cant.

Cant - A log that has two or more sides squared off.

Chamfer - A beveled edge. In timber framing, the decorative edge treatment applied to each timber.

Check - A separation of wood fibers caused by the natural process of wood drying. A check is not a structural defect, it is a natural and common event with timbers.

Circle sawn - Referring to the use of a circle saw mill used to produce lumber and timbers.  Wood products made from this type of mill contain distingtive semi-circular markings.

Collar tie - A horizontal framing member that prevents opposing rafter pairs from spreading appart. It also prevents the rafters from bowing inward when weight is placed upon them.

Come along - A hand operated ratcheting wench.  Uses include tightening joinery during assembly, as a safety tie and for pulling frame components together during erection.

Common rafters - Closely and regularly spaced inclined timbers that support the roof covering, independent of the bent system.

Compound joinery - Timber frame element cut to intersect with multi-faceted plains such as hip and valley intersections.

Corbel - A bracket of stone, wood or metal projecting from the side of a wall. Also a timber placed length wise under a beam or girder.

Dovetail - A tenon that is shaped like a dove's spread tail to fit into a corresponding mortise.

Draw knife - A tool having a blade with a handle at each  end; by drawing it toward you, you can shave surfaces.

Eased edge - See chamfer.

Energy Analysis - The application of computer projections to define a structure's expected energy consumption and costs.  This analysis is best done during the preliminary design phase to search for and correct deficiencies of lighting, appliances, hot water heating and heating & cooling.

Energy star - A voluntary labeling program of the US Environmental Agency (EPA) & the US Department of Energy that identifies energy efficient products.

Floor decking - A material used to span across beams or joists to create a structural floor surface.

FOHC - See free of heart center.

Framing chisel - Large chisel with long, heavy blades,strong enough to be hit with a heavy mallet. 

Free of heart center - A timber sawn so that the center or heart of a log is completely removed from the timber cant.

Girt - Major horizontal timber that connects posts.

Green building - A residence or commercial structure built so that it promotes energy conservation, uses environmentally friendly construction products in a sensible way and creates a healthy place to live or work.

Green wood - Freshly cut wood that is not dried or seasoned.  Wood having a high moisture content.  For literally centuries timber frame systems have utilized unseasoned timbers.

Gunstock post - A post having an increased size at its top, providing extra strength for intersecting joinery.

Half dovetail - This joint is one-half of a dovetail, used for joining collar ties to rafters, braces to posts, and for other similar situations.

Half lap - A joint in which two timbers are let into each other.

Hammer beam - A horizontal timber projecting from the top of the wall or rafter that supports a roof truss.  The design creates a large roof span with relatively short timbers.

Hammer Post - A vertical timber resting on a hammer beam and forming a triangle between it and a principal.

Hardwood - Wood of certain deciduous trees (e.g., oak, hickory, walnut, ash, etc.).

Haunch - The part of the whole timber beyond the shoulder which is let into another timber.

Housing - The shallow mortise or cavity for receiving the major part of a timber end, usually coupled with a smaller deep mortise to receive a tenon tying the joint together.

Hybrid timber frame - A residential building design incorporating timber framing into only part of the structure, while the remainder of the house is completed in a more conventional manor.

Isolated gain passive solar - The transfer of heat energy into the space to be heated from a collector that is thermally isolated from the heated space by physical separation or insulation.  (such as an attached sunspace, or greenhouse with an insulated common wall).

Jetties - A projection of an upper level structure projecting beyond a lower level.

Joist - The horizontal structural members in framing a floor or ceiling system.

Kiln dried - Reduction of the moisture content in wood by means of artificially controlling the heat, air circulation, and humidity.

King post - A central, vertical post extending from the bent plate or girt to the junction of the rafters at roof peak.

Knee brace - A short diagonal timber placed between the horizontal and vertical members of the frame to make them ridge.

Knockdown - A type of interior wall or ceiling textured finish that resembles Spanish- style stucco.  It can provide an aged appearance to the structure.  It is installed by spraying dollops of drywall compound over the surface then using a trowel to "knock down" the peaks, creating a rough, earthy and uneven surface.

Mallet - A two-headed hammer, often made of wood, rubber, or plastic. The handle is wood.

Mortise and tenon - Any joint consisting of a projection (tenon) on the end of one timber and a corresponding slot (mortise) on the other.

Natural curved timber - Naturally occurring crooked timbers usually with two sides sawn and two sides with the bark removed, used as knee braces, posts and beams.

Passive solar - Uses the sun to directly heat water, phase change material or the interior space of a building.  Energy is transferred by natural mechanisms such as conduction and air convection currents.

Peg - A hardwood dowel usually ranging from 5/8 of an inch to 2 inches in diameter.

Pendant - An ornamental termination to the low end of a hammer post, king post, queen post, etc.

Pike - A long pole with a pointed steel head used in raising bents; also called a barn pole.

Plate - A horizontal framing member used to tie together interior and exterior wall framing. The width of the plate corresponds to the thickness of the wall. Each wall has three plates: a bottom plate and two top plates.

Plinth - A defined block at the base of a column.

Post - A wood or steel vertical member that provides intermediate support for a girder.

Prinipal rafters - A pair of inclined timbers that are framed into a bent and used with purlins, or secondary rafters, or alone.

Purlin - A horizontal structural member that supports roof loads and transfers them to roof beams.

Queen post - A pair of vertical posts of a roof truss standing on the bent or girt and supporting the rafters or collar tie.

Rafter - Structural roof members placed to follow the roof slope.

Ridge pole - Horizontal timber which connects rafter pairs at the peak.

Ridge purlin - The beams connecting rafter to rafter at the apex.

Roof decking - One inch nominal or thicker lumber installed on a roof system.  Typically this decking is lift exposed to the interior.

Rough sawn - Lumber and timber that has not been planed.

Scarf joint - A joint formed by cutting an angle on the ends of boards so  they overlap.

Scribe - Shaping one member to the surface which it touches, for example, to fit a board snugly to a surface which is not straight.

Secondary rafters - Smaller sized timber rafters placed between principal rafters.

Sholder - The area of the void created when the waste around a tenon has been cut away.

SIPs - (Structural insulated panel) A building product that replaces exterior wall, roof and floor framing.  Sips are a sandwich of two outside layers, or skins, and an interior core of rigid insulation.

Slick - A wide-bladed and long-handled chisel pushed by hand to create flat surfaces.

Softwood - Any wood that is relatively soft or easily cut, from coniferous trees such as the pine and fir families.

Span - The distance between walls or columns.

Stop chamfer - Decorative end of a chamfer.

Structural Insulated Panel or SIP - A rigid panel of 3 1/2" thick expanded polystyrene (EPS) foam insulation between sheets of exterior plywood or oriented-strand board (OSB), also called a foam-core panel.

Strut - A short timber placed in a structure either diagonally or vertically, designed to act in compression along the direction of its lengths.

Summer beam - A major and usually massive horizontal timber which spans the girts or plate.

Tail - The portion of the rafter that extends beyond the wall of the building to form the eave.

Tennon - The projecting end of a timber that is inserted into a mortise.

Timber frame - A load-carrying structure of timbers ranging in size from 4x4 and up.

Timberscaping - Timberscape is the use of heavy timber systems and/or timber framing designed specifically for outdoor use.  Uses include functional structures such as pergolas and gazebos, architectural details such as signs and entryways, and timber systems that create art such as sculptures and focal points.

Trunnel - Also known as a tree-nail, a turned and tapered hardwood dowel used for securing timber joints.  See "Peg".

Tusk tenon - A tenon strengthened by one or more smaller tenons underneath forming a steplike outline.

Valley rafter - A sloping beam that forms a depression in the roof instead of a hip. Like the hip rafter, it extends diagonally from plate to ridge board. A valley rafter is needed on both hip and gable roofs whenever roof planes intersect.

Wall decking - One inch nominal or thicker lumber installed on a wall system.

Wane - Bark or lack of wood from any cause on edge or corner of a piece of timber or lumber except for eased edges.