Common Terminology
What the heck are we talking about?
Anchor Bolt: A steel bolt, which is embedded in the concrete
foundation of a structure and used to anchor the sill plate.
Angle Brace: Any timber bracing a corner at an angle across that
corner. Also called a knee brace.
Angle Iron: An L shaped length of steel frequently used to
support masonry over a window or door opening.
Base Course: The first or bottom course of masonry blocks, or
logs in a wall (sill logs).
Beam: A main horizontal member used to support vertical loads.
Bearing Wall: A wall supporting a vertical load.
Bird’s Mouth (Cut): A V shaped notch cut into the base of a rafter
that allows the rafter to sit flat on the wall or the plate.
Board and Batten siding: is an exterior treatment of vertical
boards ¾” thick and 5-8” wide with 3” battens covering the
seams.
Buck: A vertical board fastened to the ends of log sections at the
window or door openings to secure them in place and to which
the window or door jamb is fastened. Bucking- A frame around
window openings to allow expansion and contraction of the log
walls around the windows without compromising the windows.
Butt Joint: A joint made by fastening two logs together without
overlap. The two members are square cut and joined at the flat
surface.
Butt and pass overlap: The butt and pass style method of
building cabins is a construction technique which uses tightly-
pinned corners, to remove the need for any notching, to join the
logs together.
Cantilever: A structural member supported on one end but
extending beyond its support on the other end.
Caulking: Material used to seal the joints between logs or
between windows and walls, doors and walls, etc.
Chamfering: This is the process of planning the edges of the log
removing the corner to create a valley to hold the chink.
Checking: A "check" is a crack on the surface of the wood caused
by the outside of a timber shrinking as it seasons. Checks may
extend to the pith and follow the grain. Checks occur more
frequently at the ends of lumber because of the more rapid
drying in these locations.
Chinking: Either the material or the process by which gaps
between logs are filled. a pliable compound used to fill the
chamfered spaces between the logs.
Collar Tie/Collar Beam: A horizontal timber, which ties two
opposite pairs of rafters together near the middle to reduce
sagging or spreading.
Cope: A notch in a log that is cut and rounded to fit over another
log.
Corbel: A short horizontal timber supporting a girder.
Countersink: To cause the head of a bolt or spike to be below the
surface of the wood into which it is embedded.
Course of Logs: One layer of logs around the house perimeter.
Counter Sink: To allow the head of a bolt or screw, when placed
in the hole, to sit flush with or below the surface of the
surrounding material
Cove: A shallow, round shaped groove cut into the underside of a
log.
Crown Post: A central vertical post that connects the collar tie to
the bent plate.
Dead Load: Weight that a structural member is supporting by
the weight of the structure. Does not include snow, wind,
furniture, people, cars etc…
Diagonal: Reaching from corner to opposite corner at an angle.
Dormer: A window or a smaller roofed area protruding from a
sloping roof.
Dowel: Wooden peg used to hold two pieces of wood together.
Eave: The lower or bottom edge of a roof that projects beyond
the face of the walls.
Eave Soffit: The underside of the eave.
Expansion Joint: A joint, which permits expansion without
doing damage to the structure.
Fascia: The trim board that usually covers the exposed ends of
rafters or overhang.
Flashing: Weatherproof stripping used to seal joints between
masonry and wood framing or log work, and masonry and
roofing.
Floor Joists: The heavy beams that support the flooring.
Framing: The network of lumber in a building that will be
covered by finish material.
Gable: The triangular portion at the top of a wall enclosed by the
roof at the ends of the house.
Gable End: The wall in a house that has a gable roof.
Gable Roof: A sloping roof that forms an ‘A’ shape.
Gambrel Roof: A roof with one slope steeper than the other.
Girder: A horizontal structural member that supports joists.
Girt: A major horizontal timber that connects posts. provide
lateral support to the wall panel, primarily, to resist wind loads.
May also be known as a sheeting rail.
Grain: Direction of cellular arrangement in wood.
Half-Lap: A type of joint in which two timbers are lapped or let
into one another.
Header: Horizontal members between vertical posts which add
support.
Heart Wood: The wood in a tree, which extends from the middle
of the trunk outward towards the Sapwood. The older harder
nonliving central wood of trees that is usually darker, denser,
less permeable, and more durable than the surrounding
sapwood.
Hip: The sloping ridge of a roof formed by two intersecting roof
slopes.
Hip-Rafter: The rafter that forms the hip of a roof.
I-Beam: A steel beam with a cross section that makes it resemble
the letter I.
Jack Rafter: A short rafter that extends from the roof ridge to a
valley rafter or from the wall plate to a hip rafter.
Joinery: Connecting timbers by means of woodworking joints.
Joint: Any place where two or more timbers meet.
Joists: Horizontal, parallel timbers used to support the floor,
ceiling, or roof.
Joist Hanger: A metal support for the ends of joists.
Kerf: The groove left in a piece of wood by a saw cut.
King Post: A vertical support that transfers weight from the
ridge beam to the end walls or the joists.
Knee Brace: A small timber that is framed diagonally between a
post and beam.
Knee wall: A knee wall is a short wall, typically under three feet
in height, used to support the rafters in timber roof
construction.
Lag Screw: A heavy screw for wood with a bolt head.
Lateral Groove: A longitudinal groove cut into the underside of a
log enabling that log to fit over the top of another log.
Load Bearing: Carrying the weight of a structure.
Loft: The second floor in a home where the roof forms both its
ceiling and walls usually associated with houses possessing a
cathedral ceiling.
Mortise: A square or rectangular slot cut into a log, timber, or
board into which another member, usually called a tenon, will
fit.
Mortise and Tenon Joint: A joint in which a projection (tenon) of
one timber is inserted into a slot (mortise) of another timber.
Moisture Content: Percentage by weight of water in wood.
Newel: The bottom post to which a stair railing is attached. Also
post supporting sections of railings.
Notch: A recess cut into a log to accept another log intersecting it
at an angle.
• Blind Notch: A notch that does not extend completely through a
log.
• Boxed Lapped Notch: A notch cut squarely into part of each
timber
• Dovetail Notch: Log ends cut into a fan appearance resembling
a dove’s spread tail.
• Half Dovetail Notch: Log end where one side only is sloped.
• Mitered Lapped Notch: Notch that has a 45-degree slope on the
sides of the square notch.
• Round Notch: A notch in which the profile of the log exhibits
the shape of a partial circle on the underside.
• Round Sheep’s Head Notch: Same as a Sheep’s Head Notch
except that the outer cuts retain a round shape.
• Saddle Notch: Notch that is triangular in profile.
• Sheep’s Head Notch: A notch with sloped sides partially cut out
of each log.
• Square Notch: Has the appearance of a round notch on the
exterior but inside has a square interlocking lap.
Notching: The art of cutting a notch into logs.
Outrigger Beam: A log which sites atop a cantilevered logs on the
eave walls and is parallel to and extends out beyond the plate
logs. It is to this beam that the roof framing is attached.
Overhang: That part of the roof that extends beyond the outside
wall.
Peg: A wooden dowel of oak, locust or other woods.
Purloins: span between the rafters. They create a horizontal
“diaphragm” that supports the weight of your building’s roof
deck- whatever material you use for the roofing itself. They also
help make the entire roof structure more rigid. Because they add
mid-span support, purloins allow longer spans enabling you to
create wider buildings.
Piece-en-Piece: A style of building in which vertical support
posts form the main structure of a home with short lengths of
logs forming the wall panels in sections between the posts.
Pitch: The slope or angle of a roof.
Plate-Log: The log at the top of the wall that supports the roof.
Post and Beam: A style of building that uses vertical posts
supporting horizontal members and beams.
Rafter: A structural member, usually dimensional lumber that
supports a roof.
Rafter Truss: A triangle of two rafters and a horizontal brace.
Several of these make up a roof sub-structure.
Ridge Beam: A horizontal timber at the peak of the roof to which
rafters are attached. Also called a ridge board, ridge piece, or
ridgepole.
Roof Pitch: Inches of rise per 12” of roof run.
Roof Truss: A network of structural members that form a rigid
support for the roof.
Round of Logs: One layer of logs around the entire perimeter of
the house.
Saddle: The lower cut in a notch and saddle joint. The log is cut
on an angle on each side so that the surface almost comes to a
point at the top of the log.
Sapwood: The outer layer of wood in a tree that is nearest to the
bark.
Scarfed: A cut at a long angle in the direction of the timber.
Scribe: The process of cutting one log to match the contours of
another for a tight log-to-log fit.
Scribe-Fit: A building featuring tight log-to-log joinery.
Screw Jack: A device that may be adjusted to allow for the
settlement in log walls.
Settling: Loss of wall height by shrinkage and compression.
Shed Roof: A sloping roof of a single plane.
Ship lap: is a type of wooden board used commonly as exterior
siding in the construction of residences, barns, sheds,and
outbuildings. It is either rough-sawn 1" or
milled ¾” thickness and between 3" and 10" wide with a 3/8" -
1/2" rabbet on opposite sides of each end. The rabbet allows the
boards to overlap in this area. The profile of each board partially
overlaps that of the board next to it creating a channel that gives
shadow line effects, provides excellent weather protection and
allows for dimensional movement
Sill Log: The base log that sits upon the foundation.
Sills: Horizontal members that form the base of window and
door openings.
Soffit: the underside of the roof overhang.
Splice: A joint of two logs end to end.
Spline: A narrow wooden strip placed into grooves cut into two
adjoining surfaces of a log wall.
Taper: The amount of change in the diameter of a log from the
butt end to the top end.
Timber framing: is a style of construction which uses heavier
framing elements than modern stick framing, which uses
dimensional lumber. The timbers were originally joined
together with joinery without nails. Modern timber framing has
been growing in popularity in the United States since the 1970s.
Modern timber framing includes brackets and hangers.
Timber-Loc Screws: A heavy duty wood screw for applications
such as attaching rafter or trusses to the top plate, landscape
timbers, fences, decks, headers, stair stringers and more.
Replaces 3/8" lag screws. There is no need to pre-drill with
Timber-Loc. Its sharp point and aggressive threads zip right in to
the densest woods.
Truss: Structural members assembled into a rigid frame.
Through-Bolting: Threaded rod of various length used as a
tensioning device in log walls, post and beam joinery and some
timber frames.