Decking Definitions

Learn the terms of the trade from the experts

Often, the terms and words associated with outdoor decking can make building and accessorizing your deck sound like rocket science. At Deck Expressions, we've got you covered with these easy-to-remember explanations of what terms and phrases that can sometimes sound foreign! Of course, if you have any further questions or need expert advice on deck building, DIY projects, decking tools, and more. 



AC/DC – Refers to the flow of electric current. DC (Direct Current) flows in one direction only, while AC (Alternating Current) has the capability to change directions. If an electronic device is DC, but the power source is AC, a transformer will be needed to convert the power.

Aluminum – A strong metal that has a variety of uses. Aluminum is generally maintenance-free and is a very popular choice of railing materials..

 Auger Bit – A drill bit that is designed to pull the material out from the hole being drilled as it creates the hole.


Back Brushing – A technique that ensures even coverage while staining deck boards. Using a brush, the user applies the stain to the board in one direction, then brushes back over the initial stroke in the opposite direction.

Balusters – Small pillars in a series that support the rails, they are also known as spindles. Balusters are the most popular choice for infill between rails.

Balustrade – A complete section of railing.

Base Adapters – An adapter that attaches to the base of a post cap or post that enables the cap or post to fit a different size.

Base Leveler – A base for deck support pedestals that adjusts slope to create level surfaces.

Batten Strip – A belt of material used to provide attachment points to connect balusters in a railing section.

Beam – A piece of framing that is attached horizontally on existing posts to support joists.

Beer Rail – A deck board connected and placed over the top rail to create a flat surface to rest drinks and objects.

Bi-Pin – A light bulb with a two-pin connection station that connects to a specific lamp fitting for bi-pin bulbs.

Biscuit-Fasteners – Another term for deck clips that are hidden.

Blocking – Short sections of support between joists that help create stability for the deck framing..

Bracket – The part of a railing system that connects the rail to the posts.

Brazilian Rosewood Oil – An oil that is extracted from seeds of Brazilian Rosewood trees. These trees are known for being strong, flexible, and water resistant. 

Bridging – Shorter piece of framing material attached between joist to make deck framing stronger.

Brightening – Cleaners and strippers can cause the wood coloring to change slightly, causing a darkening reaction. Brighteners will offset these effects and cause the wood to "brighten" back up.

Butt Seam – When edges of decking boards align.

Butyl Tape – A rubber-based, adhesive, water-tight tape that seals. It is flexible and has the same sealing power as caulk.


Cable – An attractive and contemporary alternative to balusters as infill between rails. Cables are usually installed horizontally, although there are options for vertical cable applications. Cable is constructed of many individual wires woven into a flexible, yet strong strand.

Cam-Out – A procedure by which the torque exceeds a specific amount and slips out of the head of a fastener while being driven.

Cantilever – A strong structural beam connected on only one side to a post or structure. This needs to be solid enough to hold the weight of whatever it is supporting without the need for a second support.

Cap Head – A head fastener that is rounded.

Cap stock – A decking material comprised of composite with an exterior vinyl cap.

Chop Saw – A saw that makes straight cuts.

Circuits – A set of individual electronic components connected by conductive wires through which an electric current can flow.

Clips – Concealed decking fasteners that screw into the joist and slide into pre-cut grooves in the decking boards, resulting in fastened deck boards without any visible screws.

Collated – Fasteners held together by shred of material that breaks apart when used in an installation tool.

Composite – A substitute to wood used for decking boards and railing. Composite is a synthetic building material made of various recycled wood fibers and plastic. Composites are offered in many different color and style options.

Countersinking – A process intended to expand the rim of a drilled hole so the fastener can insert and be flush.

Crack Tool – A tool that is thin enough to apply stain in the cracks between decking boards.

Cumaru – A Brazilian Teak wood that is naturally robust and dense, similar to IPE but less expensive.


Deck Plate – A plate that is installed at the base of a post and keeps the post from sinking into the ground under the weight of the deck.

Deck Supports – Strong pedestals that hold up a decking surface for uses such rooftop patios and sheds.

Diodes – An electronic part that conducts electric current in one direction.

Driver Bit – A small metal bit that fits inside a drill in order to screw a particular fastener head.


Electroplated – A process that  and uses an electric current to coat metal.

Epoxy Coating – A thick, protective coating made of specific epoxy resins that are resistant to rust and chemical corrosion. These are often used as a finish on screws to maintain their aesthetics.


Face-Mount – Same as fascia mount, face mounts attach on the side of the deck as opposed to the top or surface.

Fascia – A flat piece of material that mounts to the perimeter of a deck.

Fascia Screws – Screws that are built strong enough to provide structural attachments to the face of a building or deck.

Fiberglass – A fortified plastic material composed of glass fibers embedded in a resin matrix.

Flashing Tape – Strong, adhesive tape that is waterproof and used to tightly seal seams.

Flat Head – A screw with a flat top that is installed into countersunk holes.

Forstner Bit – A bit that cuts into wood to create a very precise-sized hole.

Framing Screws – Screws with a sharp drill point that are strong enough to hold up the frame of a deck.


Galvanized – A zinc coating on steel or iron that helps prevent rusting.

Gate Uprights – A set of posts that can be connected to a railing panel to turn it into a gate.

Gauge – The size and capability of a wire.

Graspable HandRail – A railing that is easy to grab or hold on to. Most commercial and residential codes require that hand-rails be graspable on a staircase; if the rail is not graspable a secondary handrail may need to be installed on the stair railing section in order to meet code.

Grooved and Un grooved Boards – Deck boards that have notches down the edges in order to allow for clips to have a fastener-free look.


Hex Cap – A decorative cap with six sides made to install over screw heads.

Hidden Fasteners – Fasteners for deck boards that are concealed either as clips in between boards or as screws topped by camouflaging plugs.

Hot Dip Galvanization – A process that coats iron and steel with a layer of zinc and results in a strong material with a dull grey color.

Hurricane Zone Tested – Standards set by Miami Dade Hurricane Standards for building materials that can withstand high winds and can be used on the coast.


Incandescent – A light bulb that has a wire filament that heats up and manufactures visible light.

Inset Measurement – The depth that a component can slide inside of a cap, post, or rail to.

International Residential Code (IRC) – A residential code that sets minimum structural standards for one- and two-family dwellings of three stories or less.

IPE – A Brazilian Walnut wood known for its beautiful, dark coloring. IPE is a strong wood that is naturally resistant to rot.


Joist Hangers – A fastener that attaches the joist to a ledger or rim joist.

Joist Tape – Tape that is installed on top of the joists before securing the decking boards. This keeps moisture from causing the joists to decay.

Joist Top Accessory – A topper for deck support pedestals that includes a tab to secure and help support the joist.

Joists – A horizontal length of framing material that supports the structure of a deck.


Kick Panel – A strong piece of material that often is installed at the bottom section of screen door or a full floor to ceiling install of screen to keep it from being compromised by foot traffic.


L-Brackets – Used to attach the first plank and last plank as well as the butt seam to achieve a fastener-free decking surface.

Lags – A large wooden screw with a square or hex head.

Leads – A length of wire coming from a light or transformer that transfers power.

LED – A light source, such as a light bulb, that uses a diode instead of a bulb. It uses less energy, has a longer lifespan, and is smaller in size than an incandescent bulb.

Ledger Board – A piece of material attached to the side of a structure that the joists attach to and supports the overall framing of a deck.

Line Voltage and Low Voltage – Line Voltage is what a home is usually wired for, which is 120 volts. Low voltage tends to be at 12 volts. Low voltage lighting will need to utilize a transformer in order to bring down the voltage before use.

Lumens - measure how much light you are getting from a bulb. More lumens means it's a brighter light; fewer lumens means it's a dimmer light

Loop Installation – A deck lighting configuration where the wire runs from the transformer to the first light, from the first light to the second and so on. The last wire connects back to the transformer and creates a loop for the electrical current to run through.


Marine Oil – An oil that seals and protects wood while presenting a "hand-rubbed" finish.

Matte – A flat finish with little or no gloss.

Mill Glaze – A natural occurrence when fresh lumber is sawed, causing the grains to close. This helps prevent stain penetration.

Multi Tap Configuration Transformers – These are transformers with multiple terminals to deliver current. This is a flexible voltage system that is used for larger lighting applications where there is a large distance between lighting fixtures and lights that are more prone to voltage drop.

Mushrooming – When material displaces and engulfs the head of a screw.


Nail Screws – Screws that are used in an installation gun and shoot into the surface like a nail would.

Newel – A support post.

NiCAd Rechargeable Batteries – A battery that can be recharged using nickel oxide hydroxide and metallic cadmium as electrodes.

NiMH Rechargeable Batteries – A rechargeable battery similar to NiCad battery, the difference being NiMH uses hydrogen-absorbing alloy instead of cadmium. This enables twice the capacity of a NiCad.

Nominal Dimensions – An approximate measurement.

Nylon – A lightweight and adaptable plastic.


Oil-Canning – A term used when flat metal surfaces are compromised or deformed.

On Center – This is the distance to and from the middle of two objects. This measurement is often used when installing railing and balusters.

On Grade and Off Grade – ‘On grade’ refers to something that is on ground level, while ‘off grade’ means it has been raised up above the ground.


Pergola – A structure that creates a shaded walkway or sitting area, often seen in a garden or over a patio. These are constructed with posts that support cross-beams and offer many different decorative options.

Photo Eye – A sensor that picks up light, often attached to a transformer to dictate if it needs to turn on or off.

Pigtail – One piece of wire used to connect two or more wires.

Pilot Hole – A hole drilled as a guide for creating a larger hole.

Pitch Rail – The basis to install an under-deck system into. Pitch rails will connect to the joists of your deck.

Plugs – A piece of decking board used to hide the fastener, often rounded, that slides in the screw hole over the fastener.

Pneumatic Gun – An installation gun that uses air pressure to shoot out fasteners.

Polarity – This describes the direction of the current flow in electronics. Current flows from the positive pole to the negative and vice versa.

Poly Sprayer – A tool that holds liquid and sprays it onto any surface using a nozzle connected to a pump. This is a popular tool for staining decks.

Post Cover and Sleeve – A post sleeve slides over a post while a cover wraps around a post instead. These are often used for decorative as well as protective purposes.

Post Flash – A snug fitting collar that slides over most 4x4 wood posts to prevent moisture penetration.

Post Mount – A base for a post that will install the post to the ground or the decking surface.

Post Skirt or Flare – The cover over the base of the posts, often to cover the lags that connect the post to the deck while also adding a decorative finish.

Powder-Coat – A dry powder layer that is applied with electrostatic and cured under heat. This creates a hard finish that is stronger than paint.

Pressure Treated Lumber (ACQ) – ACQ is an abbreviation for Alkaline Copper Quaternary, also known as Pressure Treated Lumber. This is a water-based wood preservation method. The treatment makes the wood resistant to bacteria, fungi, and bugs.


Rail Plate – Horizontal top and bottom structural boards that form a connection between newel posts.

Rail Saddle – A post base with rail brackets attached.

Rim Joist – A final joist that is installed on the perimeter of the deck to cap off the row of joists supporting the floor.


Satin Finish – A smooth finish with semi-gloss.

Sealer – A non-pigmented finish that helps seal out all elements. Most often used to help prevent wood from becoming water damaged.

Self-Tapping Screw – A screw that does needs no pre-drilling. The tread has a cutting gap at the tip that removes the material that it is being driven into.

Single or Simple Tap Configuration Transformers – These are transformers with one terminal that delivers currents to a pre-set amount.

Solar – Solar refers to the conversion of sunlight into electricity. Solar lights use a solar panel to collect light during daylight hours and will turn on automatically once its light source is gone.

Splicing – Splicing occurs when two pieces of wire are joined.

Spline – A plastic piece that slides into the screen frame and helps hold the screen in place.

Split Load Installation – A wiring layout recommended when light fixtures run in multiple directions from the transformer. For this layout, locating the transformer in the center of the run reduces the effects of voltage drop.

Stainless Steel – A metal alloy that combines various elements to create a rust-resistant steel.

Stair Riser – A board installed in the vertical space between stair treads. Some deck builders choose to omit this in their stairway construction to give the stairs an open look.

Stair Treads – The flat step in the stairway. Part of a tread would be the surface you step on when you use a staircase. The tread depth is measured from the riser to the outer edge of the step. The width is the measurement from one stringer to the other stringer on the opposite side.

Stringers – Diagonal framing material that helps support stairs. These attach on either side of the treads.

Stripper – A strong solvent that removes stain, paint and various other finishes from surfaces.

Structural Post – The main vertical supports on any structure that does not need additional support.


Terminal Blocks – A connector that allows more than one circuit to connect to each other in various electronic configurations.

Thermal Cut-Off – A safety feature that stops an electric current if it starts to overheat.

Thermally Modified Wood – The process by which wood is heated with steam in a controlled environment when oxygen is not available. This enhances the structural strength and makes the wood highly resistant to rot.

Timber Bolts – A threaded fastener that uses clamping force to connect two beams with the aid of a nut.

Transformer – An electrical device that is used to increase or decrease the voltages depending on need before it feeds them into lights.

Trim Head – A screw with nibs that trim into the surface to create a countersunk finish when there is no pre-drilling. A trim head will lay flush and leave a smooth surface.


Vinyl – A synthetic material usually comprised of resin or plastic.

Volt – A unit of power. The voltage is the amount of force electricity travels through a wire.

Voltage Drop – The voltage loss that occurs when a circuit faces resistance to its current flow. This causes the load to work harder with less voltage and often causes lights to flicker, dim or go out altogether.


Wattage – A unit of power. Wattage is typically used to express the rate of energy conversion over time.