This construction glossary for home and outdoor structures is free to everyone, courtesy of Western Timber Frame™. If you use this glossary or anything else at this site, thank you for giving credit to Please feel free to link to this site! Thank-you. Marilynn

Click here:> Timber Frame Pergola Kits if you would like more information quality Timber Frame Arbor, Pergola, Pavilion or Gazebo kits or have one built for you!

aerator – A round screened apparatus that screws on to cover the spout of a sink, introducing air into water for a smooth flow.
abutting joint – A joint that is between two boards in which the grain of one is angled to the grain of the other, usually at 90°.
abutting tenon – One or two wood elements that meet in the same mortise.
accessory structure – A second structure on the same lot as a dwelling.
acoustical board – A board material that is used to restrict and control the transmission of sound.
aggregate – A mixture of loose particles such as sand, gravel, and pebbles added to an cement agent to make concrete.
allowance – A sum of money granted or set aside for a particular purpose.
aluminum – A nonmagnetic, lightweight metal used in construction. Aluminum is used extensively in electrical cables and cooking pots because of its excellent electrical conductivity and heat transferring properties.
arbor – A kind of lattice work formed of; or covered with vines, branches, wood or man-made materials for shade, a shady retreat or covered walkway.
anchor bolts – Bolts that secure a sill plate into concrete, or masonry.
arch – A curved or a flat structural element spanning over an opening.
arch beam– A beam that is arched
architect– A person who is a learned professional who plans, designs, organizes, makes or creates a structure or object.
architecture – Art of science of frame, structure or workmanship in building; esp. the art of building houses, bridges and construction for the purpose of civil life.
architectural – Product of a work of architecture, a class of construction.
area wells – Barrier walls constructed from corrugated metal or concrete formed around a basement window to hold back the surrounding dirt.
backfill – Earth or material used in the replacement of excavated earth around or against a basement, space or foundation wall.
backing – The lumber installed between wall studs giving it additional support rather than into drywall.
ballast – 1. A transformer that provides starting voltage through the gas in a florescent lamp. 2. A layer of coarse gravel/slag for which concrete is placed over or ties are set.
baluster – One of many short columns or supporting, vertical (often vase shaped) elements used for a handrail or stair treads.
balustrade – A complete railing system with rail, posts (balusters) along a stairway or walkway.
barge – A beam rafter that that lies horizontal to support shorter rafters.
barge board – (bargeboard) A board that hangs from or covers the projecting fly rafter end of a gabled end.
barge spike – Square long spike with a chisel point.
barite – A barium sulfate mineral used as an aggregate in concrete for radiation shielding.
base – The lowest portion of anything upon which the whole bears upon.
Western Timber Frame™ uses a massive mortised dovetail joint connection system design called the “The Dovetail Difference™” throughout our timber construction process creating very strong rigid joints. On the test pictured here it didn’t give until it hit 11,000 lbs!

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…beneath an Outdoor Timber Frame Shade Creation

basement – The bottom story that is partially or completely below grade the first floor of a building.
bat – A half-brick.
batten– A narrow strip or strips of wood used to cover joints perpendicular to parallel pieces of wood holding them together.
bay window – A window and space that projects outward from a wall or building.
beam – A horizontal structural element that supports a load such as a rafter, girder or purlin transferring the load to vertical elements, such as columns and walls.
beam test – The method used to measure the strength of a beam.
bearing – A structural element such as a column, beam or truss used to support or to steady.
bearing partition – A partition that supports any vertical load in addition to its own weight.
bearing plate – A steel plate placed beneath a beam, column, truss or girder to distribute the load to support a member.
bearing point – The point of a bearing or structural weight load is concentrated, transferred onto the foundation.
bearing pressure – The present load that bears down on a surface, divided by the area of the bearing surface.
bearing wall – Any wall that is supporting a vertical load in addition to its own weight.
bearing header – A beam or horizontal structural element placed perpendicular to joists or over an opening such as a door or window or framed over a chimney or stairway.
bedrock – The layer of earth used as a subsurface that is strong enough to support a structure.
bid – A signed proposal for a work to perform, a formal offer in accordance to specification of a project at a particular price.
Bifold or bifolding door – A door with two leaves, each having two panels that are hinged together in the middle, supported by a track. The door opens in a smaller area than a standard door.
bill of materials or BOM – A description and list of materials and all the needed supplies with the quantities required to be able to complete an assembly or subassembly.
binding post – An electric wire or cable attached to a post that holds a connection to it.
biodegradable – Is able to break down, decompose and naturally decay, returning to the earth.
bipass doors – Doors that slide by each other and commonly used as closet doors.
bit extension – A rod held on one end by the chuck and equipped on the other end to hold a bit to extend the required depth of the shorter bit.
bit gauge – A metal piece that projects outward from a bit to limit the depth it is able to penetrate.
blanket – 1. Soil or rock pieces used to contain or direct flying fragments. 2. Insulation used to protect fresh concrete as it cures.
blind dovetail – A joint that has the appearance outwardly of a simple miter joint with a dovetail concealed within it.
blind joint – A joint that is entirely concealed.
blind mortise – A mortise that goes in but not clear through.
blind mortise and tenon joint – A joint that is between a blind mortise and the stub tenon.
blind tenon – A tenon that fits into a blind mortise
block – A solid piece of wood or hollow concrete masonry or other unit like a glass block used to fill in space between a formwork. Usually they are rectangle or square.
block beam – A flexural element in a structural design composed of single blocks joined to each other by prestressing.
blocked or door blocking – A shim used between a door frame and a vertical wall frame.
blocked rafters – Short 2×4’s that are used in weak frame lumber to keep a rafter from twisting in the middle and at the ends.
blue print – A copy method used architectural drawings used to describe the design of a structure, prepared by an architect for the purpose of planning, estimating and securing permits for the actual construction.
blue stake – A utility company locates and spray the ground with paint and/or marks with flags to show where their particular service is located underneath the ground.
board foot – A unit of measurement used for lumber. One board foot is equal to 1 inch thick by 12 inches wide and 12 inches long. Nominal sizes are assumed when calculating the board feet.
board measure – A measuring system using one board foot to measure the quantity of lumber.
boom – A truck that is used to hoist up heavy material into place, to set trusses or a heavy beam into place.
bottom chord – The lower or bottom horizontal member of a truss.
bottom plate – A post that lays on the subfloor in which a vertical stud is installed, also referred to as the sole plate.
brace – A piece of framing lumber that is applied to a wall or a floor in order to strengthen a structure or temporarily support a framing until it is completed.
brazed joint – A term in plumbing when a fitting is brazed to be watertight and gas-tight.
breaker panel – The electrical box composed of circuit breakers where electric power is distributed to the home into each circuit plug or switch.
brick lintel – An angled metal iron that the brick sits on, particularly above a window, door, or opening.
bridging – Small elements of wood or metal that are inserted diagonally between floor joists or rafters to brace and spread the load.
buck – To connect or operate often used in reference to a door or window frame or rough frame openings.
building codes – Ordinances that govern the way in which a structure can be constructed or modified.
building insurance – Insurance that covers the structure of the building.
building paper – A term used for materials used in building that such as paper, felt and similar materials used in building.
bull nose – Usually is referring to the rounded corners on drywall.
bundle – Refers to a package of shingles which commonly is made of three bundles per square and twenty-seven shingles per bundle.
butt edge – The lower edge of the shingle tabs.
butt hinge – A conventional type is where one leaf attaches to the edge of the door and the other to the jamb.
butt joint – The place were two ends of timber meet end to end or edge to edge without overlapping.
by fold door – A door with two leaves, each having two panels that are hinged together in the middle, supported by a track. The door opens in a smaller area than a standard door.
by pass doors – Doors that slide past each other.
cabinet – A case, set of drawers or cupboard intended valuables often closed with doors or fitted with drawers.
caisson – A cylindrical hole drilled into the earth for a structural support of a wall, porch , patio or other structure. The shaft if filled with reinforcing bars and concrete.
cantilever – A structural overhang that is supported only on one end such as a floor that extends farther than the foundation wall or a bay window.
cantilever footing – A tie beam on a footing to counterbalance and resist overturning an asymmetrical load.
cap – The top element of a column, pillar or fireplace.
cap flashing – The part of the flashing that is attached to a vertical surface which prevents water from flowing behind the base flashing.
capital – The original loan amount borrowed or the principal part of a loan.
capped rate The mortgage interest rate that will not go over a specified value throughout a specific period of time, but it can fluctuate up and down below a certain level.
casement – Wood frames or metal enclosures such as in a window sash that may be opened with hinges that are attached to the vertical edges.

casement window – A window that has hinges allowing it to swing open like a door.
casing The wood trim molding that is installed around a window or door.
caulking – A thick fluid material that is used to seal up gaps in between two surfaces or pieces of siding or in places such as the corner of a tub wall. Fills in joints or asphalt to prevent leaks.
CCA or chromated copper arsenate – A high pressure pesticide that is forced into wood for protecting it from wood boring insects and fungus.
ceiling joist – A parallel framing element used to support a ceiling and is also supported by larger beams, bearing walls or girders. They are also referred to as roof joists.
cement – A substance which is mixed with water and used in a soft or pasty state to join stones or bricks in building, to cover floors etc.
ceramic tile – Ceramic is any product made from the earth and a tile is flat baked ceramic piece used to finish a floor or wall most often found in a bathtub or shower enclosure, backsplashes and countertops.
chair rail – A wooden molding on a wall around a room to protect the wall from being damaged by the back of the chairs.
chalk line – A line that is made with chalk used for guidelines and alignment purposes by snapping a cord or string that has been dusted with chalk.
chip board – A manufactured wood panel made from wood chips and glue. It is also sometimes called wafer board.

circuit – The electrical path that flows from a power source to an outlet and back to a ground.
circuit breaker – A switch that is located inside of an electrical breaker panel or box to shut off portions of power to areas of the house.
class “A” – The optimum fire rating that is issued by Underwriters’ Laboratories on roofing. This fire safety is required in some areas for roofing.
class “C”: This is a minimum fire rating that is issued by Underwriters’ Laboratories for roofing safety in materials.
clean out: The opening that is providing an access into a drain line and then closed off with a threaded plug.
clip ties: Metal protruding wires that from a concrete foundation wall that held panels in place for the foundation at one time.
cold air return: The ductwork and grills that carry the air from the room back into the furnace.
collar: Also referred to as a vent sleeve, a collar is a flange that is formed over a vent pipe that seals the roofing above the opening of the vent pipe.
collar beam: A one or two inch thick member that connects roof rafters opposite to each other to stiffening the roof structure.
column: A vertical structural element that supports a load.
combustion air: The duct work that is used to bring fresh from the outside air to the furnace or hot water heater.
combustion chamber: The section of a boiler, wood stove or a furnace where burning takes place which is molded or lined with bricks or insulation that has been sprayed.
compression web – An element of a truss system connecting the top and bottom chords providing downward support.
compressor – 1. A mechanical device that compresses the air or gas. 2. A machine that generates compressed air to supply pressure for construction sites and run tools.
concrete: – A composite of cement, sand, stone, gravel, gravel, slag, and water mixed together to harden onto stone like material for patios, basements, foundation walls, etc.
concrete block – A concrete brick used for masonry building cast into a standard shape and size.
concrete board – A fiberglass or concrete panel that is used primarily as a tile backing material.
condensation – The conversion of moisture from the air to water in the forming of water drops.
condensing unit – A mechanism that pumps in a refrigeration system that vaporizes refrigerant by compressing and liquefying it and then returning it to the refrigerant control.
conditioned air – The air inside of a building that is controlled in temperature.
conduction – The direct transferring of heat energy through a material.
conductivity – The rate at which heat is transmitted through a material.
conduit – A pipe or tube used to channel the flow of liquid or used to enclose and protect electrical wires.
construction drywall – A way of construction where the interior wall applied dry generally in the form of sheets of material or paneling.
consulting engineer – A person who is licensed as an engineer hired to perform an engineering task.
continuity tester – A device that gives information as to whether a circuit is capable of carrying electricity.

contractor – A person who is contracted to perform a construction in accordance to a contractual document.
control joint – Grooves that are tooled into concrete flooring to control the place concrete should crack.
controlled fill Regulating and inspecting the moisture content, lift depth and equipment for compaction in the backfill or embankment.
convection – The currents that are created by heating the air that will then rise and pull the cooler air in behind it.
conventional loan – A mortgage loan that is not insured by any government agency.
coped – The removal of the flanges from the top and bottom a metal I-beam to permit it to fit into the web of another I-beam creating a T.
coped joint – Where two pieces of molding intersect, one fitting into the contour of the other.
corbel – A triangular decorative construction element supports a load such as a mantel, ledge or horizontal shelf.
corded door – A door or divider that is suspended, sliding from a track and folds into accordion pleats.
corner bead – A strip of sheet metal formed to place around the outside of the corners of a wall before applying drywall mud.
corner board – Corner trim the exterior of a frame structure against which the end of the siding is finished.
corner braces – Braces placed diagonally to strengthen a framed structure.
counter flashing – A metal flashing that is primarily used on a chimney to prevent moisture from entering.
countersunk bolt – A bolt with a flat head that tapers down to the shank diameter so it can be driven in deep enough to be flush with the top of a hole that is countersunk.
countertop – The surface material that covers cabinetry, such as is used in kitchens and bathrooms.
culvert – A drain pipe that is installed underneath a driveway that runs parallel to or near the street.
cup joint – A joint used in copper tubing that is straight. A swaging tool it then driven into the end that is to be joined to enlarge it for another end to fit over it for a solder connection.
cupping -The warping of a board that causes it to curl up along the edges.
cross tee – A short “T” beam made of metal that is used to suspend a ceiling system, bridging the spaces between the main beams.
D-grade wood – Wood that has been graded for interior use only, as in backs and inner plies.
dabber – A soft brush with a rounded tip to apply varnishes or polish and finish gilding.
dabbing – Using a sharp tool on a stone to give it a rough pitted appearance.
dado – 1. The section of a column between the base and the top or cornice.
2. The ornamental paneling that is above the baseboard of a wall.
3. The flat-bottomed groove that is cut in one board to receive the end of another board. If the cut is grooved along the edge of the board, it is referred to as a rabbet.
dado cap – A chair rail or cornice along the top of the framed dado.dado joint – A joint that is created by fitting a piece of wood into a groove at a right angle to half its depth in thickness across the other.
daily report log – The day to day recorded happenings on a construction site, such as subcontractors, accidents, visitors, progress and weather. This record is considered a legal record in many states.
dalle-de-ver stained glass – Another way of saying faceted stained glass. Stained glass that is held together by cement of epoxy instead of lead or zinc cames.
dam – A barrier in the trap way of a toilet controlling the level of water in a toilet bowl.
damper – 1. A blade or louver inside of an inlet, outlet or air duct that is adjustable, regulating the air flow.
2. A pivotal plate that is cast iron positioned below the smoke chamber of a stove or fireplace to regulate the drafts.
dao – 1. A heavy, moderately had wood from the Philippines and New Guinea, variegating in color. It is mostly used in cabinetry and interior finishing.
dap – A notch cut into one timber to fit into the end of another.
daub – 1. To rough up a stone surface by using a special hammer to strike it.
2. Rough coat something with plaster.
dash-bond coat – A thicker slurry consisting of cement, sand and water that is applied the outside of a concrete wall using a whiskbroom or brush as a bonding for another coat of plaster.
datum – The elevation base by which other elevation are referred.
datum line – The reference line of elevation.
daylight compensation – An lighting system that saves energy and is controlled by a photocell decreasing the lamp’s intensity as daylight increases.
daylight factor – Calculation of the natural light that enters a building.
db – Stands for decibel.
dead bolt – A type of a lock on a door that turns both directions with a key or turning.
dead end – 1. In a tendon, it is the opposite end to one end that stress is applied to.
2. In plumbing, it is a vent or drain line that is closed off by a cap or plug.
dead-end anchorage – The anchored end in a steel tenon opposite to the jacking end.

deck – 1. A structural system over which a roof covering, pergola or arbor is applied.2. Sheeting or wood installed over floor joists, trusses or rafters.3. Flooring, raised walkways or designated outdoor flooring.
deck clip – 1. An accessory that is shaped like an H placed between the plywood sheets that are used as roof decking to prevent deflection and unevenness. This allows for thinner plywood sheets to be used without blocking underneath the joints.
2. A metal fastener that is used to attach the roof deck units onto the structural frame.
3. An accessory that is made for attaching stiff insulation material onto a roof deck.
decking – 1. Heavy duty slabs or form that are used to save stripping costs.
2. Planking that is used on roofs or floors.
3. Sheets of corrugated metal used for constructing roofs.
deflection angle – In surveying, a horizontal angle as measured from the spreading out of a preceding travel line to the next line.
deformed metal plate – A corrugated metal plate used at a vertical joint giving to interlock between sections.
degradation – The deterioration or breaking down of a surface due to the elements.
degree – 1/360th of a circle’s circumference or a round angle.
degree of compaction – Using a standard formula of measure to see how dense a sample of soil is.
degree of density – The measure of how compact something is.
dehydrochlorination – The reaction that happens chemically when sunlight and vinyl’s binder, polyvinyl chloride cause the surface of the vinyl to yellow and break down.
delamination – The separating of materials usually due to adhesive failure, such as laminated wood beams and veneers.
delivery – The transferring of a product from one place and person to another.
demarcation – A fixed line in masonry that marks a boundary limit.
dense concrete – Concrete that contains a minimum number of empty voids.
dentils – Square blocks place under a cornice separated from each other, used ornamentally.
depth gauge – A tool to measure or test the depth of drilled holes, grooves, dados and other recessed sections of a structure.
derated concrete – Concrete having had chemicals added in gas form to create air holes making it lightweight.
design – A preliminary graphic or architectural concept of a building or structure.
design load – An analysis of a load upon structure under the worst possible conditions.
developed area – An area where improvements have been implemented.
dial saw – An attachment that is used in conjunction with a power drill to cut a hole.
diamond blade – A circular blade used in a saw to cut concrete, brick and other hard materials.
die – A tool that is used to cut thread on a pipe or bolt.
diffused light – Light that is reflected from off of a surface instead of radiating from a direct light source.
dimension lumber – Lumber cut between 2″ to 5″ thick and is 2″ or more.
dimensionally stable – Any building or structure that does not change shape or become altered noticeably with load, moisture and weather conditions.
dipper – The digging bucket or shovel of a backhoe.
direct solar gain – The solar heat that is gained when sunlight shines in and heats a room or the walls and floors store the heat.
displacement ventilation – The ventilation that naturally through convection processes moves warm air upward and out of a room or building.
distributed load – The load that is evenly distributed across the full length of a surface, floor or structural member measured in length or weight per the area.
divided tenon – Two side by side tenons that are both in the end of another member.
D-line crack – One of many randomly and closely spaced cracks with a pattern in a concrete surface.
dock – A platform that is raised for loading and unloading trucks.
dolly – A device used to wheel heavy loads or a block of wood used to cushion the blows of a hammer.
dome light – A dome shaped light covering made of glass or plastic.
door – A movable element that is used to close over an open area used to enter or exit a room or enclosure.
door butt – A hinge for a door.
door clearance – The space and the distance from the top and bottom of a finished door.
dormant beam – A larger beam that supports a smaller beam.
double floor – A finished floor that is constructed with a sub-flooring beneath it.
double rafter – Two rafter installed in a pair alongside each other.
doughnut – A washer that is used to increase and hold forms, to reinforce steel during the pouring of concrete, also sometimes referred as a watertight seal used in installing a toilet.
Douglas Fir – A Pseudotsuga taxifolia Douglas Fir is a softwood found throughout the Western United States. Douglas fir has a strength to weight ratio that has an unparalleled for its modulus of elasticity, shear, compression, tension laterally to grain and other characteristics that give it greater strength. Douglas fir is a the builders premium choice for sound architectural commercial and residential building in the U.S.A..

All of Western Timber Frame’s arbor, gazebo, pavilion and pergola kits are constructed from #1 Grade rough sawn SFI Certified* timbers. Douglas Fir (DF) is the number one choice by architects and engineers for structural timbers. It is dimensionally stable and universally recognized for its superior strength and its high density provides excellent nail- and plate-holding ability.

DF has documented better performance against strong forces such as winds, storms and earthquakes. DF timbers are perfect for a wide range of projects. With the ability to be used both indoors and out, it is the most versatile material for nearly any building project.
dovetail or dovetail joint – The dovetail has a trapezoidal angled shape that interlocks with another angled board creating a snug fit that gives the timbers an even greater power to perform with woods inherent ability to dampen resonate frequencies while maintaining its beautiful aesthetic appearance. This innovative design makes installation faster and more convenient, and creates very strong rigid corners.

The Dovetail Differece ™ – Termed by Western Timber Frame™ for their award winning Post-to-Beam Dovetail Connection System combining heritage architectural principles with state of the art technology in all of their timber frame DIY pergolas, pavilions, gazebos, arbors and outdoor structures.
dovetail half-lap joint – A dovetailed joint with a mortise cut only halfway through to adjoin a piece giving it the appearance of having a butted or mitered joint on the other end.
dovetail saw – A back tenon saw with a strip to stiffen on the bak and teeth to saw for dovetails.
downpayment – A partial payment for construction of a project of the contracted price made between a owner and the contractor at the beginning to a contractual agreement.
drag strut – A structural element that transfers the lateral force of one vertical element to another.
drainage – A process where waste water is carried away from.
drawings – The graphic designs of the dimensions and location of a project.
dressed lumber – Processed lumber with a smooth surface and standard uniformity of size.
drip irrigation – A watering system for a landscape that uses a low water pressure and tubing that is placed on top of the ground and are meant to conserve water by dripping on targeted plants.
dry-powder fire extinguisher – A fire extinguisher that is hand held discharging dry powder using a compressed gas.
dummy joint – Grooves in the surface of concrete to appear like crack control.
duraluminum – An aluminum alloy used mostly in rolled sheets.
durometer – A mechanism used to determine how hard a material is.
dyne – The unit of force that is required to accelerate using one gram of mass at the rate of 1 cm per second.
ear – A ornamental or structural projecting part or piece, also a metal piece that projects to nail a pipe to a wall.
earthquake load – The amount of force an earthquake exerts against a structure.
eastern red cedar – An aromatic red colored wood with a fine texture used mostly for closet linings and shingles.
eastern S-P-F – Eastern pine, spruce or fir type softwoods used primarily as structural lumber for framing, posts, sheathing and beams.
eastern spruce – Fir type softwood used primarily in structural lumber for framing, posts, sheathing and beams.
eaves – The bottom edge section of a roof that extends beyond the outer walls of a structure.
ebony – A very dark tropical hardwood used mainly for carving and ornamental work.
eccentric load – The load or force upon a section of column that is not symmetric with the central axis which causes it to bend.
ecology – The study of living things and their relationship to the environment.
economy brick – A modular brick with a cored middle. The standard nominal dimension is 4x4x8 inches and the intrinsic dimension is approximately 3 1/2x 3 1/2 x 7 1/2 inches.
edge grain – Lumber or timber that is cut at an angle that reveals the annual rings that intersect the wide face.
edge guide – An attachment bit placed on a router to ensure a straight cut from the work surface’s edge.
edge joint – A joint that is created by two pieces of boards joining to form an angle or a corner.
elastic – Any material that can be deformed by a force from outside and return to the initial state it was.
elastomer – A polymer that is temporarily deformed from stress and returns to its initial shape and size when the stress is released.
elbow – An angled or bent pipe, conduit or fitting.
electric drill – A hand, portable motorized tool that is sued to bore holes in a material.
electric generator – A mechanical powered mechanism that transforms power into electrical power.
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elevation – The vertical distance that is relative to a particular reference point.
elm – A type of strong hardwood with high density and twisting interlocking grains used mainly for veneers, planks and ornamental landscaping.
encased beam – A enclosed metal beam inside of concrete or similar material.
erection stress – The stress of a load that is applied during the erection of a structure.
espalier – The framework or trellis that is used to direct the branches of fruit trees or any other decorative plants that grow in a determined design to improve the air circulation and sun exposure for ornamental purposes.
eurythmy – The term used in reference to architectural purposes is an order and harmony in proportion.
exterior plywood – Layers of veneer that are bonded together with waterproof glue to form a plywood.
FHA strap – The metal straps used to repair bearing walls, hang stairs and tie together wall corners and splices.
f rating – The letter f is used to symbolize the measure of stress that is in a piece of lumber. The higher f rating the stronger the lumber.
face block – A masonry concrete unit that has a ceramic or a plastic faced surface that is often either glazed or polished.
Fahrenheit – A scale for temperature respectively from 32°freezing to 212° boiling points.
false joint – The groove in stone or a masonry block that gives the appearance of being a joint.
fan (mechanical) – A machine that consists of rotating blades or vanes which act upon the air to increase air flow.
fatigue – A material becoming weaker resulting in cracking or complete failure due to load or repeated loads.
fiberboard – Any of a variety of panel products formed by heat and pressure applied to bonded wood fillers, such as chipboard, hardboard or particleboard.
fixed beam – A structural beam that is fixed rather than hinged.
fixture joint – A connection for electricity formed by taking two conductors and twisting them together and bending it over.
flagstone – A flat and irregular shaped stone that is usually about one to four inches thick used as flooring or paving.
flange angle – A shape that is angled as one part of a flange in a built up girder.
flange brace – The brace that laterally supports the flange of a girder, beam, joist or column.
flat arch – An arch that has only a slight curvature.
flat varnish – A varnish that when it dries has no or low gloss.
fleck – A small marking or spot in wood usually caused from irregular growth or different characteristics.
floodlight – A light that projects luminaire that is designed to light up an area at a higher level.
floor load – The amount of live load upon a flooring for which it was designed that is estimated by the building code for weight and activity.
flue – The passage used to let combustible products pass in a chimney that is heat resistant and noncombustible.
fluorescence – Light that is visibly emitted from such as phosphor and absorbs radiation at shorter wavelengths.
flush joint – Any joint that has a surface flush with an adjacent surface.
foam concrete – A cellular concrete that is made lightweight by infusing a concrete mixture that is not hard with foam that is prepared by generating gases into the mixture.
footing – The foundational portion of a structure that spreads the load directly to the earth.
forked tenon – A tenon cut in a rail that is inserted into a mortise.
forklift truck – A powered vehicle that is equipped with strong forked prongs that can raise or lower used to move object from one place to another.
foxtail saw – A small saw that is used to prepare a dovetail.

gable – The peak end or ridge of a building that extends past the eaves.
gallon – A standard measure for liquid. An American gallon holds 8.34 pounds of water wherein the British gallon holds 10 pounds or approximately 4.54 kg of water.
galvanize – The process of immersion or electroplating that puts a protective coating of zinc on iron or steel.
gang nail – A multi-toothed connector made from steel used to fasten a heavy duty timbers that is used most often in roof trusses and floor construction.
gang nail plate – A steel plate also referred to as a gusset or fishplate, that attaches on both sides of each truss joint.
garbage disposal unit – An motorized electrical device that grinds up food waste that mixes with water as it is disposed down through plumbing drainage.
gas – Fluid in the form of air that is neither independent of shape nor of volume able to expand indefinitely.
gas concrete – Concrete that is light weight and with insulating qualities from a mixture of cement alkalies with aluminum powder reacting from hydrogen gas that produces voids in an unhardened mix.
gate valve – A valve that will let you completely stop but not change the flow inside of a pipe.

gazebo – A freestanding or attached roofed structure open on all sides to provide shade and shelter. Gazebos are ornamental used in a landscape for a place to rest and take in a view.

General Contractor – A person who a contractor who enters into a contract with the owner of a project for the purpose of the construction of the project and takes full responsibility for its completion.
gas lateral – The trenched area on a property where the gas line service is located.
gauged arch – An arch that is constructed from bricks having a wedge shape with joints from a common center.
G-clamp – A large clamp shaped like a G that screws down to clamp two pieces of wood with glue together.
geotechnical engineering – A specialist in the field of civil engineering, the mechanics of soil and geology in the design of structural foundations.
gib-and-cotter joint – A joint that a gib with cotters is pulled tight securing the members together.
girder – A large beam of wood or steel that is used to support great concentrated loads.
ground joint – In masonry it is the close-fitted joint most often without the use of mortar. A close fitted joint in between metal surfaces that are machined.

groundwater – Water that comes from an aquifer or a subsurface water source.
grout – A mixture of wet cement, water and sand that is placed into the crevices of masonry or ceramic to seal in between the different pieces, also mortar added into cavities of the masonry work to fill them solid.
gudgeon – A metal pin or a dowel that is used to join stones or blocks. Also part of a gate hook that is used to fasten to a gate post.
gun – 1. Equipment designed for shooting shotcrete. 2. A pressure cylinder for pneumatic spraying of freshly mixed concrete. 3. A spray gun. 4. The tool that shoots nails and embeds them into wood.
gypsum backerboard – A type of gypsum board which is not as smooth as a wall board with a gray paper surface that is used specifically as a base for tile or gypsum wallboard.
gyp board – A panel drywall wall board or gypsum. with a core of Gypsum from a chalk like rock, which covers the interior walls and ceilings.
H clip – A small metal clip with an “H” form that fits at the joints of two wafer boards or plywood sheets to stiffen up the joint.
half mortise hinge – A door hinge that has one plate mounted on the jamb while the other mortised plate in mounted into the door stile.
half timbered – A building with foundation, supports and knees all constructed with timber filled with brick and masonry between the timbers.
half truss – A jack truss on one side that spans from the top rood truss to the wall at an angle.
hand brace – A hand tool to bore wood with a stationary bar bent at one end and a chuck at the other.
hand punch – A stationary tool that is designed to press into to mark a surface for the alignment of holes.
hardware – Metal fittings such as door knobs, hinges, bolts, brackets etc.
hanger – Any class of hardware used to as a support such as supporting a beam or joist.
haunch – An extension that protrudes from the foundation wall that a concrete porch or patio sits on for support.
header – A beam placed perpendicular to a joist which other joists are framed to for a chimney, stairway, etc. The horizontal structure over an opening, such as a door or window.
heading joint – Two timbers that are connected in a straight line, end-to-end forming a joint.
hearth – A brick or stone covered fireplace used to heat. In a fireplace the hearth is the place where the fire burns.
heavy timber – 1. Construction that requires exterior wall to be noncombustible with a minimum two hour fire resistance rating. 2. Rough timbers with a minimum dimension of 5 inches.
hip roof – A roof that rises on all sides of a building by inclined planes.
home run – electrical – The electrical power cable that running from an electrical box, plug, or switch to the main circuit breaker panel.
honeycomb – 1. Pitted surface from the incomplete filling of concrete often caused from not enough vibrating after a pour. 2. In sandwich panel construction or doors that are hollow, paper that is impregnated with resin in between face panels.
hook bolt – A bolt bent in an “L” shape on the unthreaded end.
hook-and-butt joint – The scarf joint of timbers ends locking positively together to resist tension.
hot tub – A large tub, spa or small pool with heated water that is used for hydrotherapy and relaxation usually located outdoors.
housed joint – Most often refers to a perpendicular joint that is formed wherein the entire thickness of one timber’s end is placed into a corresponding groove, dado or housing of another timber.
Howe truss – A truss having vertical and diagonal webs that absorbs tension vertically and compression diagonally.
hudee rim – A metal frame that is used to secure in a sink within a countertop.
I-beam – An steel beam having with a cross section that resembles the letter I used for long spans over wide openings.
I-joist – An I-joist is composed of two main parts, a web and a flange. The web is lain between the top and bottom flange in an the “I” shape, typically made from plywood or veneer lumber.
impeller – 1. A device that is used to force gas that us pressurized in a set direction. 2. A ventilation device used to move air through rotation. 3. Part of a rotary pump that uses centrifugal force to push fluid in and out.
incandescent lamp – An electric light that produces light through a wire filament that is heated at a high temperature until it glows.
inspection – An examination or visual inspection by an public official to ensure that a construction work complies with contractual documents.
intermediate rafter – Also referred to as a common rafter, it is a wood member for framing that extends form an eaves rafter plate to a ridge board.
International Building Code or IBC – A building code when adopted by a jurisdiction that covers building not more than three stories high for family dwellings.
interstate commerce – Selling, buying and exchanging products or good across state lines.
intrusion alarms – A device that detects by sensor the forced entry or breaking in of a facility.
irrigation – A sprinkling system for a lawn.
J channel – The metal edging that is used in drywall giving the edge a nicer finish .
jack post – A metal structural support that can be raised and lowered to meet a required height.
jack rafter – A rafter spanning from the wall plate valley over to a hip ridge.
jamb – The lining of a doorway or window that a window or door closes against.
joggle beam – A beam which is built up wherein joggles are used for securing the component members in a respective position.

joint – Where two components touch surfaces being held together by nails or glue etc. or interlocking each other with no fasteners.
joint cement or joint compound – A powder mixed with water, sometimes called spackle or drywall mud that is used to finish a wallboard and the like.
joint tape – Mesh plastic fabric, paper or or cotton tape that is used with plaster or mastic to cover joints between adjacent wallboard sheets.
joist – A wood 2 X 8’s, 2 X 10’s, or 2 X 12’s that are set parallel to each other supporting a flooring or ceiling, also supported by bearing walls, beams or girders.
joist hanger – A “U” shaped metal piece that is used for support at the end of a floor joist and then attached to a bearing beam or joist.
judas – A small opening or hole in a door that is used to see in for surveillance.
junior beam – A lightweight, steel structure of sections rolled to a whole I-beam shape.
jute – The fiber from a plant from which a yarn is made for burlap. rope and carpet backing.
K factor (sheet metal) – A design used to calculate the amount of sheet metal needed to leave a bend to for a final dimension.
K truss – A truss in a “K” shape formed with panels and cords.
kerf – A crosswise saw or groove cut in wood or stone to allow for bending but not completely through.
kettle – 1. With asphalt it is a container used to hot mop a roof. 2. A container for paint or a vessel that glue is melted in.
key plate – An escutcheon or protective plate surrounding a keyhole or light switch; a flange for piping to cover a hole in a floor in which a pipe is.
Christenson-arrow-keystone Keystone

keystone – Usually a wedge shape at the uppermost top of an arch binding or locking it together.
kibble – A bucket or device by which water, materials, tools etc. are pulled up from a shaft.
kiln dried lumber – Lumber that has been dried in a kiln to control the amount of moisture in the lumber.
kilogram – A metric unit of the mass and the weight that equal to 1000 grams.
kilometer – A metric unit of the distance that equals to 1000 meters.
kilowatt – An electrical unit of 1000 watts.
kilowatt hour or KWH – An electrical energy measured to the equivalent of 1000 watts for one hour of power.
kinetic energy – In physics, kinetic energy is the energy an object has that is associated with its motion.
kinetic friction – The friction that is between two surfaces that are resisting relative motion moving in contact with each other.

[pl_modal title=”Decorative Support Bracing” type=”btn” colortype=”success” label=”Knee Brace”] standard-knee-brace-pic
…For an Outdoor Western Timber Frame Shade Creation

kneepads – Protective rubber and foam pads that are used by workers to to strap on their knees when kneeling on floors.
knee wall – Typically, a short wall that is under one meter or three feet high underneath the slope of a roof.
knockout – The cylindrical section of a junction or outlet box that can be removed to install a conduit connector.
knot – A tree branch/limb surrounded by growth of the stem causing a knot to appear on a cut surface.
knuckle – The large portion of a hinge wherein the pin is inserted.

landing – A platform or floor between a the top or bottom of a flights of stairs.
landscape – Improving the natural scenery by modifying a site with such things as planting trees and ground cover and hardscape, etc.
landscape timber – Large timber that has been treated ussed in decorating or as barriers and retaining walls in landscape.
langly – A measure of the solar radiation that is equal to 1 calorie for every square centimeter.
lantern (roof) – An architectural element is a raised structure on the top of a roof or skylight space that allows for light to be admitted, also called a cupola.
lap joint – A joint that is made by placing one board partly overlapping top of another.
lath – An insulation board, metal, gypsum or wood building material which is used to fasten onto a building frame for base for plaster.
lattice – A framework formed from criss-crossed wood strips.

ledger strip – A strip of lumber that is nailed into the side of a girder or beam to forma support on which the joists rests.
light – Space inside of a window sash that is used for a single glass pane.
lintel – A structural member that is horizontally supporting the load over to top of a door or window.
lookout – In architecture a lookout is a cantilever or wooden bracket supporting an overhand or roof sheathing, usually concealed from view.
louvered roof -A series of horizontal slats that open to permit ventilation while excluding rain, sun or light.
lumber – Lumber is the American term and timber is the British term for harvested wood that is cut into boards or planks.
lumber, dressed size – The nominal dimensions of lumber are larger than the standard actual size of finished lumber.
mantel – A decorative trim or shelving around or over a fireplace opening.
maintenance – The continual upkeep of a property or equipment.
maisonette – A smaller house or an apartment that has two floors.
majolica Any earthenware that has an opaque glaze or overglaze.
male thread – The outer thread on a pipe, screw or fitting.
malleable – Any metal that is capable of being formed, bent and/or hammered without breaking.
mallet – A hammer with a wooden head.
mansard roof – A roof that rises on all four sides by with inclined planes and all the sides have a lower and upper pitch.
masonry – A concrete block, bricks, stones, tiles or other material bonded with mortar to form a wall or buttress.
mastic – A material used for a cement or protective coating in setting toile or waterproofing for a thermal insulation.
metal lath – Metal sheets that are are sheared in a press with diamond shaped voids enabling the metal to stretch.
millwork – Most all building material produced from finished wood and manufactured in a mill are termed as a “millwork”.
miter joint – A joint that made by joining to parts, usually at a 45° angle forming a corner which is usually a 90° angle such as seen in picture frames or pipe organs.
moisture content of wood – The percentage of the weight of water that is contained in the wood.
molding – A strip of having a projecting surface that is used for ornamental and decorative purposes.
mortar typesType M is the strongest type of mortar generally used for foundations, walks and retaining walls.
Type N is used generally for masonry that is exposed above the grade and used where there is harsh exposure on exterior walls.
Type O is used on load bearing walls in places were the compression stress is not more than 100 lbs. per square inch and is not in places that freeze or thaw or has excessive moisture.
Type S is used in places where it is required to have a high resistance to lateral forces.
mortise – A cavity or chamber cut into a timber to receive a tenon from another timber or board. There are several types of mortises, such as an open mortise, stub mortise, through mortise, wedged half dovetail, through wedged half dovetail, etc.
mullion – The vertical bar that divides the frame between a window, door or opening.
muntin – A small piece which divides the glass or opening of a door.
ankle-xray-mortise-tenon-brClick here to learn more about a mortise and tenon joint system.
natural finish – A transparent finish that does not alter the original color or grain of the natural wood very much.
neutral wire – Usually a wire that is color coded white that carries electricity from the outlet and then back to a service panel.
newel post – The starter post at the ending of a railing or balustrade on a staircase is fastened.
nonbearing wall – A wall that supports only its own weight without any other load.
nosing – The edge that projects from a molding to the edge of the of a stair tread.
notch – A groove that is cut crosswise at the ending of a board.
nozzle – A part connected to a heating system that sprays the fuel from the air and fuel mixture into the combustion chamber.

outdoor lighting – Summer parties, good food and a night full of friends and laughter can create memorable moments. Lighting on a pergola or timber structure is a way to add elegance to a property, garden or landscape, day or night. Lighting also adds security, creates depth making the property seem larger and more inviting.

A pergola can ensure a wonderful experience and the guests can still relax and enjoy themselves even if there is an unexpected change in the weather. It also is a wonderful place to sit back and put up your feet in quiet solitude enjoying the stars, reading a good book or watching an outdoor movie.

oak loor – A common oak flooring that is usually installed in tongue and groove strips.
oak – A strong, tree with a hard, heavy wood mainly native to North Hemisphere.

oatmeal paper – Wallpaper that is made by the sprinkling of sawdust over an adhesive on a surface.
obelisk – A tall four-sided, tapering, narrow, sculpted stone monument with a pyramid-like shape on the top.
oblique slip fault – A trans-impression that occurs when an area of the Earth’s crust slips diagonally along a fault plane.
obscure glass – Glass that is frosted or ground so the view is obscured yet still transmits light.
obtuse angle – An angle of that is over 90° but less than 180°.
obtuse triangle – A triangle that has one that is angle over 90°.
octave – The frequency difference doubled between harmonic vibrations of sound.
oculus – A circular opening in a dome, eye or round window.
OD – Abbreviation for the outside diameter.
outdoor kitchen – An outdoor living area that is designed to prepare food for dining and entertaining. An outdoor kitchen can be as simple as a barbecue cooker with a counter to as elaborate as grills, sink, refrigerator, lights, fan, cabinets, stone countertops and more.
outdoor living – Usually refers to designated areas that are equipped with features that bring conveniences enjoyed indoors into the outdoors for more comfortable and convenient outdoor environments.


outfall sewer – A large sewer that leads from a lower end of the collection system over to disposal container.
outlet box – A box which houses the electrical outlets.
outlet – 1. An exit. 2.The electrical receptacle in which electrical appliances can be plugged.
outline Lighting – The arrangement of gas tubing or incandescent lamps that call attention to particular features such as a sidewalk, building shape or window decoration.

outrigger – A structural member that projects out from the main structure, providing additional support and stability.
outrigger scaffold – A scaffolding work that is supported on outrigger beams that is cantilevered from out of the building or structure that is being worked on.
outdoor oven – An oven suited to bake food in elements of the outdoors.
overcoat – A second coating or topcoat.
overhang beam – A beam supported by two or more supports with the ends projecting beyond the support.

p-trap – A P-shape that provides a trap to seal in waste or soil pipes that is used in sinks and lavatories.
paint grade – Describing a product made from wood that is more suitable painted than with a clear finish.
partition – A wall that subdivides any space that is within a room, building or story.
patio – A patio is most often constructed from concrete or stone and creates an outdoor space that adjoins a residence for a walkable surface.
pavilion – The term pavilion is used interchangeably with gazebo, both are architectural structures that are free standing, open supported by columns. Historically when a pavilion was placed strategically to take in a view is was referred to as a gazebo. Today, a pavilion is usually symmetrical with an enclosed roof, normally free-standing but can be attached.

peacock’s eye – A circular mark in wood as is often seen in bird’s eye maple.
pea gravel – Gravel that has been screened wherein the particles that pass are within a 3/8″ or 9.5 mm sieve and a number 4 or 4.75 mm sieve.
peak load – The maximum load a design, device or structure can carry over a designated length of time.
peat moss – 1. A moss that grows in a wet environment. 2. A moss partially decomposing that is used as a mulch.
pedestal pavers – Stone or concrete pavers that are suitable for foot traffic.
pediment – A decorative, often triangular, unit over a doorway.
penitent post – A post that is shorter used to against a wall to support a tie or arched beam.

pergola – A pergola is used interchangeably with arbor, gazebo and pavilion. A pergola provides shade and is usually supported by vertical posts that support cross beams giving protection from sun and implement weather.

Porte-cochère – A porte-cochère is a main or secondary coach/carriage porch or portico-like structured entrance to a building through which motor vehicle or carriage can pass to let out occupants while being protected from the weather.
periderm – A secondary protective covering that forms itself on non woody plants and trees composed of cork producing tissue.
pentachlorophenol – A chemical pressurized to penetrate wood for preservation.
pilot hole – A hole used to guide a nail or screw for drilling a larger hole.
polyurethane insulation – Describing a number of insulation products produced from polyurethane, such as spray foam, rigid boards and pourable mixes.
pop valve – A value designed for safety that is designed to open immediately when the pressure of fluid is greater than the force of a spring.
porch – A porch is an architectural area that allows for people to pause and relax comfortably before entering a building. It can be enclosed with framed walls or open with columns. They are many styles and types of porches.
quad outlet – An outlet that has four ports.
quarry tile – A machine or man-made clay tile that is used to cover a floor or wall.
quarter round – A trim molding with a quarter circle cross section.
quarter-sawing – Logs are most often cut into quarters before being sawn into boards. The grain on quarter sawn boards run 45° up to 90° angles up to the face side of the board.
quoin – Stones used in brick or stone buildings that extrude out from the building itself to create an impression of strength and uniform cut blocks larger than the other bricks or stone.


R-value – The number of minutes that is required for 1 BTU to be able to penetrate one square foot of a given material for every degree of temperature difference that is between two sides of the material.
racking – Having the tendency to distort as a rectangle that changes into a non-rectangular parallelogram.
rafter – A timber roof beam forming the main body of the roof’s framework.

rafter – drop in rafter – For a timber frame DIY arbor, gazebo, pavilion or pergola kit, the drop in layout rafter beam are part of Western Timber Frame’s easy to install design features that makes a DIY kit so simple to install. Each layout beam has been precisely cut to neatly lay each rafter into place without any guesswork. It is so easy!

rail – The horizontal section of door frame or window.
railing – An safety guard made from rails and posts, also a banding used in cabinetwork.
raked – A pitched or sloping characteristic.

reducer – The pipefitting that can connect pipes of different sizes.
reinforced concrete – The concrete that has been embedded with steel to give the tensile strength and reinforcement on the assumption that concrete and steel act together in resisting forces.
relieving arch – An added arch placed over a lintel for additional support.
relative humidity – The quantitive ratio of the present water vapor to the amount present in a saturated condition at a temperature; expressed as a percentage.
render – A cement or a lime based covering internally or externally over a wall.
retaining wall – A wall that is constructed to hold back a bank of soil.
reveal – The top or the side faces of a door or a window opening.
ridge – The highest point of a roof wherein two slopes come together.
ridge tile – A half round or angular shaped tile for creating a weather-tight ridge on a roof.
riser – The vertical portion of a step or stair.
rough cast – A rough finish on an external wall.

saddle – A second small roof behind the back side of the chimney on a fireplace that is used to divert water away the chimney.
sack mix – The measure of Portland cement that is in a cubic yard of mixed concrete.
sand float finish – The lime and sand mixture for a textured finish on a wall.
sanitary sewer – A sewer system that is designed to collect waste water from the kitchen, laundry and bathroom drains.

sash – The one frame that holds the glass of a window, most often the movable portion of the window. One light frame that contains another one or more lights of glass.
sash balance – A device that holds a window vent up usually operated by a spring to keep it in place.
saturated felt – A felt which is has been saturated with tar or asphalt.


scratch coat – The first plaster coat, which has been scratched in order to form a bond for the second coat.
screed concrete – The leveling of concrete during a pour.
screed plaster– A wood strip that is used as a guide for plastering.
scribing – Cutting or fitting woodwork to produce lines to an irregular surface.
scupper – The opening for a drain in a wall or a drain in a floor or downspout.
sealer – A material that is clear or pigmented applied over raw wood for the purpose of giving it a finishing seal on the surface.
seasoning – Drying and removal of the moisture in green wood.
self-sealing shingles – Shingles with adhesive that is self-sealing.
semigloss paint or enamel – A paint or enamel that when it dries has some luster but does not have high gloss.
septic system – A waste water treatment system that septic drains into and is designed for liquid to soak into the ground.
service entrance panel – The cabinet that houses the main power where the electricity comes into the home’s wiring system.
service equipment – The main control of fuses, circuit breakers, and switches.
service lateral – The underground power supply line.
setback thermostat – A thermostat that has a clock that can be programmed on or off, up or down for different times of the day or week at various temperatures for heating and cooling.
settlement – The shifting in a structure which is usually caused by the cycles of underground freezing and thawing.
sewage ejector – A pump that is sued in the lifting up of waste water into a gravity sanitary sewer line.
sewer stub – The junction from the city’s sewer system to where the sewer line from a home is connected.


Hammocks, Swings and Benches
Western Timber Frame’s pergola kits are engineered to easily hold a large swing, or multiple hammocks. Swings are a nice addition to pergolas or gazebo kits for any purpose. It is a breath of fresh air to have a beautifully designed pergola that is structurally strong enough to hold swings as well.
sewer tap – The physical connection point from where the sewer line from the home connects to the city’s main sewer line.
sheathing or sheeting – The structural panel covering of wood or plywood that is installed over floor joists, studs, rafters, or trusses of a structure.
shed roof – A roof that has only one sloping plane.
sheet metal work – All the components of a structure that uses flashing, sheet metal, gutters, and downspouts.
sheet metal duct work – The system installed for heating for distributing warm or cold air from the furnace into the rooms of a building.
sheet rock – Drywall, wall board or gypsum which is a manufactured panel made from gypsum plaster and encased in a thin cardboard.
shim – A small piece of scrap lumber that is used to wedge or force under or behind a furring strip or fill in a framing member to force it into position.
shingles – A roof covering of made from slate, asphalt, asbestos, tile, wood, or some other material that is cut in a set length, width and thickness.
shutter – A louvered frame used on the side of a window usually for ornamental purposes but some are made to close over a window for protection.
siding – The exterior finish that covers the outside walls of a framed building.
sill plate or mudsill – The bottom of an exterior wall frame that horizontally sits on the top of the foundation.
sill seal – The fiberglass or foam insulation that is installed between wood plate sill and the foundation wall to seal any gaps.
skylight – A window in the roof of a building.
slab concrete – The concrete pavement for a driveway, garage, or basement floor.
slab door – A door that is rectangular without any hinges or frame.
spacing – The distance between two individual members in a construction.
span – From eave to eave the distance that a member carries a load without support between structural supports.
structural shade – Shade from structures made specifically to provide shade in outdoor settings, such as an arbor, gazebo, pavilion, pergola, etc.
tenon – A tenon is a projection member on the end of a timber for insertion into a mortise. There are many types of tenons, such as a stub tenon, through tenon, fixed tenon, biscuit tenon, tusk tenon, teasel tenon, top tenon, half shoulder tenon, hammer head tenon, pegged tenon, pinned tenon, etc.
trellis – A structure or frame of latticework, used as a screen or a support for climbing plants and vines, also a bower or summerhouse.
U factor – The rate or measure of heat loss is the U factor.
U bolt – A U-shaped bolt that has two threaded arms that extend from a curved base to accommodate nuts. It is useful in things like attaching pipes onto a machine.
ultimate load – The maximum load that a structure is able to bear before it experiences failure of a component to hold strong.
unbuttoning – The breaking off of a head of a rivet to unfasten a steel rivet connection.
underpinning – A solid laid foundation that is below the ground level to support and strengthen a building.
valley – The internal angle that is formed when two sloped sides of a roof come into a junction.
valve – A device used for liquid or gas, to stop, start, or regulate the flow of liquid through or from piping.
vapor – A gaseous substance.
vapor barrier – The material applied over exposed walls or as part of a blanket insulation that is used in retarding and prevent condensation of water vapor into walls.
varnish – A thicker drying oil or resin that is suitable to spread over a surface for a transparent coating.
vehicle – The liquid part of a material used for finishing that has a binder that is non-volatile as well as a volatile thinner.
veneer – Very thinly sliced sheets of wood.
vent – A duct or pipe that lets air flow as an inlet or an outlet.
vermiculite – A lightweight material that has insulative qualities used for insulation in concrete floors and acoustical plaster.
volatile thinner – A liquid that evaporates easily used to thin or the consistency of a finish without changing the relative volumes of the pigment and the nonvolatile vehicles.
vapor barrier or retarder – A barrier placed between the insulation to retard the water vapor in a building.
vent pipe – A vertical pipe that protrudes through a roof for the ventilation of gasses.
ventilator – The device that is installed in a roof to ventilate the inside of a building.
wafer board – A wood panel that is manufactured from one to two inch wood chips and glue that is sometimes used in place of plywood.
wall out – When a painter sprays the paint onto the interior of a home.
warping – Any material that is distorted.
waste pipe and vent – The plastic plumbing pipe that carries the waste water into the city’s sewage system.
water board – A water resistant drywall that is to be used in wet use locations such as a tub and shower.
water closet – Another term for a toilet.
water meter vault or pit – The box or cast iron bonnet with concrete rings that hold the water meter.
water-repellent preservative – A liquid applied to wood to give the wood water repellant properties
water table – The underground water location and the distance vertically from the surface of the earth to the underground water.
water tap – The point where the water line from the home connects to the city’s main water system.
weatherizing – The installing of weather proofing with storm doors and windows, weather stripping and caulking in cracks to reduce loss of energy for heating and cooling.
weatherstrip – Thin strips of material installed to prevent the passage of air and moisture around doors and windows.
weep hole – A small hole that is in storm window frame lets moisture escape.
wind bracing – Wooden blocks or metal strapping that is installed in a diagonal of a wall to keep in from twisting or falling.
window buck – The square/rectangular box installed in a concrete foundation or block wall for a window to be installed into.
window frame – The stationary framed section of a window unit where in a window sash will fit into the frame.
window sash – The movable window that slides or lifts from the window frame.
window stop – A piece that prevents a window from falling out of a window frame.

wire mesh – A heavy gauge grid of wires that are welded together for the purpose of reinforcing concrete slabs.
wire nut – A plastic device that is used to cover and connect bare wires to each other.
Wonderboard ™ – A panel that is constructed from concrete and fiberglass that is used as a backing material for ceramic tiles.
X-brace – A structural engineering usage wherein the lateral load is reduced on a building by the load being transferred into a distinctive X shaped bracing on the exterior as seen on the exterior of the John Hancock Center built in 1969.
xeriscaping – A type of landscaping that uses native plants that need less water and are more draught tolerant and hearty to thrive with less need for pest control or fertilizers.
x-ray shielding or protection – An absorbing c material used to encase and shield with lead sheets or sheets containing lead in a plaster or drywall and to keep radiation from escaping from the room.
xyst (xystus or xystos) – Pronounced as “zist” it is another term for a shade covering! In ancient Greek and Roman architecture was a promenade or portico, a shaded walkway lined with trees or covered colonnade.
Y-branch – A plumbing pipe that is shaped like a Y to branch out.
Y-fitting or wye – A ‘Y’ shaped pipe.
Yankee screwdriver – A round notched spiral ratchet screwdriver.
yard drain – A catch basin that by design collects water that pools in low spots.
yard lumber – A category of lumber usually up to 5 inches thick, also lumber in a lumber yard graded in size and for its intended use.
yardage – The area of surface material that is equal to a cubic yard or yards
yellow pine – Yellow pine is more than one species of tree native to the Southern United States. Yellow pine is used extensively in building and construction for plywood and dimensional lumber.
Z-bar flashing – A galvanized metal bent flashing installed horizontally over a trim board on the exterior of a brick, window or door that prevents water from flowing behind the trim or brick work into the home.
zone – A section or area of property that serves as a loop for heating and cooling or an area that is watered by a sprinkling system.
zone dam – The internal dam in a framed curtain wall at the both ends of the horizontal mullion. It is most often a rubber plug that is installed at the uniting of the horizontal frame to the vertical frame, designed to keep any water from infiltrating into the glass lite.
zone valve – The device that is used to control the water flow into the building that is controlled by a the a zone thermostat.

zoning – A specified governmental process wherein a property’s use is limited to where you can what you can and where you can build according to their codes.
zoning permit – A government issued document that permits a particular piece of land to be used for a specific purpose.

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By |2017-05-19T15:12:27-06:00September 13th, 2014|Pergola Kits, Technical, Timber and Wood, Timber Arbors, Timber Pergolas|3 Comments

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  1. Kaylene Forrester December 19, 2014 at 8:43 am

    Wow, this is a great glossary. I’m a writer, and have been working on a story where the main character is a construction worker. It’s hard to write about someone who’s in a profession you’re unfamiliar with, but with web links like this, I can make my character sound authentic. Thanks for all the work on this, you should make it available to writer’s websites, so others can take advantage of it.

  2. Jc Hargraves January 18, 2020 at 10:40 pm

    I just had to say I love the your shade structures!

  3. Western Timber Frame January 20, 2020 at 10:54 am

    Thank you, for taking the time to tell us.

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