parts of a deck, Parts of a Deck: A Guide to Deck Terminology

Parts of a Deck: A Guide to Deck Terminology

Decks are a great addition to any home or business. If you’re thinking about adding a deck to your property, it’s essential to know what goes into the construction of this type of project. You can install decks on houses, commercial buildings, and even boats. They use wood, concrete, or composite plastic boards that look like wood but won’t rot or splinter as natural wood does over time.

When planning a deck, there are plenty of terms and acronyms to keep track of.

Here’s a guide to some of the most common words you’ll see when it comes to decks:

  • Balusters
  • Balustrade
  • Beams
  • Blocking
  • Bridging
  • Decking
  • Fascia
  • Flashing
  • Footings
  • Hardware
  • Joists
  • Ledger
  • Piers
  • Post Anchors
  • Railing
  • Railing Posts
  • Rebar
  • Rim Joists
  • Stairs
  • Stringer
  • Support Posts

Parts of a Deck


Balusters are vertical posts spaced evenly along the decking and support the top rail.. Balusters create a physical barrier to keep people and pets from falling off decks and balconies, which makes them essential for safety reasons. Check with local building codes before installing new balusters to ensure they meet height or spacing requirements.


 A balustrade is comprised of an assembled top rail, balusters or spindles and often a bottom rail, posts, post caps, and decorative finials. Balustrades can come in many shapes and sizes: some are straight while others are curved; some have decorative designs; some have more than one level; some even have multiple types of railings in one! It all depends on how much money you want to spend on them but don’t forget about functionality too, because if they aren’t safe enough, why bother?


Beams or girders are horizontal pieces of lumber that support your deck. They’re usually made from pressure-treated lumber but can also come from other materials.


Blocking supports joists and other components of a deck. You can make them from either wood or steel. It’s usually installed between joists or at the ends of the joists to prevent them from moving. If you’re building a deck with more than one level, blocking supports the beams that connect each level.


Bridging is a structural member that supports the decking and prevents twisting. Bridging also acts as a load-bearing member, meaning it helps to hold up the weight of everything placed on top of it. The smaller pieces of wood used to bolster the strength of supporting joists are bridging.

The purpose of bridging is to provide a strong foundation for your deck so that you can enjoy using it without worrying about any issues with construction integrity.


Decking is the surface of the deck. You can make it from wood, composite, capped composite, HDPE, or PVC.

The composite decking will be the most visible part of your deck, so it’s essential to choose a material you like that will withstand the elements. You may also want to consider whether or not you want boards that are straight-cut or tongue-and-groove style.

The latter can be more expensive and requires more maintenance, but it also provides a stronger deck. The American Wood Council (AWC) has very particular rules for decking construction, which you should follow to the letter.


Regarding decking, fascia is an essential part of architectural design. It’s a horizontal board that covers up exposed parts of the framework and conceals any less appealing structural aspects from view.

Fascia boards are attached to the outside perimeter of your deck frame and around any posts on your deck surface. These boards are usually made from pressure-treated wood, cedar, or pine and serve as both aesthetic appeal and protection against rot and other elements that can damage your beautiful home addition.


Flashing is the metal that connects two different materials. You can use it to seal the joints where two pieces of wood meet and prevent water from entering the deck. Flashing is common in vinyl, copper, or stainless steel materials.

Make sure to follow International Residential Code (IRC) guidelines when installing flashing on your deck.  This will ensure a sturdy structure that can withstand different weather conditions.


Footings are the foundation of a deck. They’re a vital part of the overall deck design and structure. A foundation or footing made of concrete is where you’ll find the posts that hold up your deck. The footing is vital to your deck because it keeps it stable and sturdy. The whole structure could be compromised and fall apart if you don’t have a good foundation.

Concrete footings are poured and finished before the framing is complete; this allows them to support deck loads evenly to hold up for their intended uses.


The hardware is all of the small pieces used to connect the various parts of your deck, including structural screws, lag screws, bolts, nuts, fasteners, steel connectors, and more. The hardware helps connect your deck, and it’s essential to make sure that you use high-quality pieces for this.

For example, if you’re using lag bolts or screws, make sure they are stainless steel so they won’t rust over time. Good quality hardware will make sure your deck stays together without fail. 


Joists are the main components of the actual structure of your deck. They’re horizontal beams that support your decking, made from treated lumber. The joists are held in place by ledger boards, rim joists, and other pieces that make up the frame for your deck. You should install the joists at regular gaps and they should be strong enough to support the decking materials.

The size of your joists will be directly proportional to the weight they can support. 

Not sure what size you need? Ask us! We can help you figure out how many pounds your deck will hold so that you know what kind of lumber to use.


The ledger is a horizontal plank on the outer perimeter of a deck, connecting posts to the house and supporting joists (or beams) that support subflooring.

The most common type of ledger uses pressure-treated wood, which resists moisture better than untreated lumber. For this reason, they are often installed outside of posts rather than inside them.


Piers are the vertical columns that support a deck. They are usually made of concrete but can also be wood or steel. Piers attach to footings to assist with weight distribution and structural support. They may affix to the ground instead of on footings in specific environments.

It is vital to space piers evenly throughout your deck project. Check your local building code to see how far apart they need to be.

Post Anchors

Post anchors are sometimes used to secure the posts to the footings. They help keep them elevated slightly so that water does not damage them. They can be made of metal or plastic, depending on your preference.

If you’re worried about making a mistake when you build a deck, call a professional contractor who will create an attractive and functional addition for you!


The railing is the safety barrier that prevents people from falling off your deck. It’s a horizontal structure on all sides of your deck and is comprised of several components, including rails, railing posts, balusters, and spindles.

Railings connect using metal brackets called tension devices (which come in many shapes and sizes). Each component has a predrilled hole for securing the connection. Some decks have railings with wooden pickets between each post; others use metal pipes as posts for their railings.

The top or bottom surface of these posts can be flat or rounded, so they don’t interfere with anyone sitting on them.

The material used for the railing depends on what style you want it to have: wood, aluminum or composite may seem like an obvious choice, but there’s also stainless steel! Plus, there are ways to ensure they’re durable enough so they won’t warp over time, even when they face exposure to weather conditions such as rain or snowfall.

Railing Posts

Railing posts are the vertical posts that support the deck railing. They must be sturdy and tall enough to keep users from stepping over the edge of the deck. 

Railing posts are typically attached to the deck with lag screws (or other fasteners). Though they support the railings, they are not intended to support the deck’s sub-structure. 


Rebar is a steel bar used to reinforce concrete. It is usually high-strength steel, but you can also find rebar made from aluminum and other metals. You can use rebar for many purposes, including reinforcing the deck, footings, and piers. Rebar provides strength and rigidity to concrete, which makes it an excellent choice for supporting a deck. It can also help to reinforce the posts and beams of your deck, so they don’t bend or sag over time.

The rebar is placed inside the formwork for the concrete, forming an interlocking pattern in the concrete itself. This helps prevent cracks from forming in your deck over time, which ensures that it stays strong for years to come.

Rim Joists

Rim joists are the outermost boards on a deck that run parallel to its edges and support the deck joists. They help support the weight of your deck and provide strength and rigidity to the overall structure. To build rim joists, you can use pressure-treated wood and composite materials such as plastic or fiberglass. 

The rim joist attaches to a wall or post using an approved fastener. This keeps it from pulling away from the house or post, which would cause structural damage over time. If your deck is attached to a house, you’ll likely have a rim joist. However, if it’s attached to a free-standing post, the rim joist may be absent or incomplete. 


Stairways are yet another component of a deck that can use various materials. Many people choose to use wood when constructing their deck stairs, but other options are also available. You can also build stairs from stone, metal, or even concrete. The material you use depends on the overall design of your deck and what you want to achieve with it.

For safety reasons, your stairway must be secure and sturdy enough to support the weight of anyone who may use it. This means that you should always have at least one handrail on both sides of the stairs whenever possible so that users can hold on while ascending or descending them. If you do not have enough room for two handrails, choose a design where one side has railings while the other does not.


A stringer is a horizontal member that connects the posts and supports the decking. A stringer can be made of wood, plastic, or metal, depending on whether you want a natural look or an easier-to-maintain surface. 

Support Posts

Another critical component of a deck is the support posts. These vertical timbers are usually made from pressure-treated lumber. They’re attached to your footings, supporting and elevating the overall deck structure. Support posts help to strengthen your deck floor by stabilizing it against movement caused by weather conditions or shifting soil.


It can be hard to know where to start when building your DIY deck, and we get that. We hope this guide has given you a good overview of the various parts of a deck system. If you have questions, we’re here for you. Feel free to contact the team of dedicated experts at Decks & Docks for assistance with all of your deck and dock supply needs. At Decks & Docks, we carry everything you need for your deck project. Just stop by any one of our locations today!