How to Build a Deck | Trex composite or AZEK Deck
How Platinum Decking will build you a 25+ year deck
Deck Footing and Foundation
No different than building a house, the key to any good structure starts with the foundation. Not only does the footing support the weight of the deck, but they also prevent frost heave. Frost heave is where the ground over time moves the concrete footing during the natural freezing and thawing. There are 2 keys to preventing this.
The first key is making sure your deck footing is deep enough where it is below the frost line. In Illinois and Wisconsin, every footing installed by Platinum Decking is 42″+ deep. Based on the International Building Code, this is a safe depth where we live we help prevent frost heave.
The second key to preventing frost heave is using an entirely different foundation system called a Diamond Pier. Diamond Pier’s were originally designed for commercial applications where the ground was not strong enough to support a traditionally concrete footing. A Diamond Pier is designed to replicate the strength and support tree roots bring to a tree. With long metal rods that reach below the frost line, Diamond Piers provide more uplift and frost heave protection than a traditional concrete footing.
When it comes to framing, the first key begins months before the project starts. Ensuring the use of high-quality lumber is one of the most important steps. Unfortunately, the quality of treated lumber over the years has gradually decreased and the price has actually increased. This is due to a variety of different factors involving government regulation, lumber mill strikes, and Canadian trade regulations.
Platinum Decking takes great pride in our lumber selection and supplier relationships. We build with the only number 1 and number 2 green treated Southern Pine. Not only does this ensure your deck frame will be strong, but it also ensures your deck will be level and square. Often times lumber will be warped or have small but significant width differences. These width differences create esthetic issues when using a composite material. For example, a 2×10 can be anywhere between 9″ thick to 9.5″ thick. This inconsistency can create a “wave” effect when composite decking is laid on it.
Preventing the “wave” effect is something that we take very seriously at Platinum Decking. Ensuring that we have some of the highest quality lumber helps with lumber consistency. In the rare case we notice differences with lumber widths, we will take matters into our own hands. Once the deck joists are installed, we will use a planner to shave the thicker pieces of lumber down to the correct size. This does take additional time but will help eliminate the undesired “wave” effect.
The Deck Ledger Board
After the footings are installed, the deck ledger board is next. The ledger board attaches the deck to the house. We use large screws called Ledger Loks (made my FastenMaster https://www.fastenmaster.com/ ) that connect the ledger board to the floor joist of your home. Tieing into your floor joists is very important in giving your deck the support and strength that is needed.
For decks over a certain height, we also use 4 Simpson Tension Tie’s that adds additional support and strength to your deck project (https://www.strongtie.com/). No corners are cut when it comes to building a deck that is safe.
The Deck Frame
Once the ledger board is securely fastened to your home’s floor joists, the actual framing begins. Depending on the deck height and load requirements, we will either use 4×4’s or 6×6’s as the deck posts. The posts are fastened to the footings with a galvanized post base. This will keep the posts from sliding off the footing over time. Your security fastened deck posts will then connect to your beam which will be the main support for all of your deck joists. Your deck joists will be spaced either 16″ or 12″ on center depending on the type of decking material and configuration you choose. The size of the deck joist and beams depend on the load capacity needed to support the weight of your deck.
4×4’s are also used to fasten and secure the post that supports the railing. We use 2 Thruloks or Thrubots to make sure your railing posts are secure and safe to carry the code-required amount of weight. Your railings are the last line of defense to keeping your friends and family safe when enjoying time on deck.
The final framing step is installing stiff blocking throughout the deck. Stiff blocking is installed between the jobs that help with lateral movement. Lateral movement can be one of the major causes of a deck collapse. Therefore is very important when building a deck frame that will last 25+ years and stand up to the elements of time.
6×6 Posts to beam connection- Deck Frame
Deck Framing- Stair Stringers
Deck Stiff Blocking
Installing the decking and Fascia
Once the deck has been framed, it is time to start installing your new composite decking and fascia. This process may vary slightly depending on the type of material and the design that has been chosen. Our system of installing the deck boards requires color match screws for the perimeter and hidden fasteners for the infill.
Normally, the first board laid is the “nose board”. The nose board is the board furthest from the house. Once this is installed with color matching screws, we start laying boards by moving toward the house. Other than on the perimeter boards (also known as “picture frame” boards) and breaker boards, we typically use hidden fasteners wherever possible. Hidden fasteners give the deck a clean look and hold the boards tightly in place. Taking frequent measurements after every few deck boards are installed is a common practice that helps to ensure we are installing the boards tight enough with no extra spacing. It makes the process a little longer, but it is worth it to have straight, evenly spaced decking. The correct spacing between each board is roughly a quarter inch. This spacing allows air to flow through the deck. The airflow is important for drying the framing lumber and decking off after rains or is exposed to moisture.
After the decking is installed, the deck fascia is soon to follow. Fascia is installed on the rim-joist that runs around the perimeter of the deck. Fascia has no structural use but adds significant aesthetic value. When looking at the deck, the fascia will cause your deck to really stand out and is a dead giveaway that you have a beautiful composite deck or PVC deck. Fascia is either composite or PVC and is fastened with specific color match fascia screws.
Vertical deck skirting is also a potential option. This is deck boards placed below the fascia running vertically. The picture below is an example of white fascia with gray vertical deck skirting.
Railings and Deck Lighting
After the footings, framing, decking, and fascia are complete, we get to jump to the railings and deck lighting.
Railings come in four different sections. They either come in stair railings; 6 or 8-foot sections, and horizontal railings; in 6 or 8-foot sections. They can be cut down to fit smaller sections but do not come in longer sections. As the railings are installed, most of the lighting will be installed at the same time. Post cap lighting and downlighting are the two we install the most but there are other lighting options that we also install. Stair riser lights and recessed deck lighting are fantastic options if they are within the budget. We also offer dimmer remote controls that can be paired with your lighting system.
Black Trex Transcend Railings
Trex Select Railings
Black Trex Signature Railings
Cocktail railings are also a popular option. A cocktail railing is a composite 2×4 (only comes in Trex Transcend Tropical colors) that is fastened to the top of the railing. A cocktail railing adds a unique look and surface to rest a drink on. This is a great option if you plan to host dinner parties or frequently have family and friends over.
ADA handrails are also installed when necessary. International Building Code requires a stair railing to be “graspable” in order to ensure users get a secure grip. Some railings do not meet this requirement and need an additional hand railing. When needed we will add a Trex ADA handrail. These come in Black, bronze, and white.
Trex Deck Lighting- post cap and recessed lights
Trex Stair Riser Lights- Cocktail railing installed on Trex Transcend Railings
Please keep in mind that no two decks are the same and many projects require some customer strategies. This is a generalized blueprint and changes as we build your custom project. With that said, this hopefully gives you a much better idea of how Platinum Decking builds some of the highest quality decks in Illinois and Wisconsin and focuses on the details!