A Comprehensive Guide to Deck Support Systems

The Importance of Proper Deck Supports

Decks have become essential to many homes, providing a relaxing outdoor space for family and friends to gather. However, they can be dangerous and collapse without proper deck support. That’s why it’s crucial to understand deck support’s importance and the different support systems available. In this guide, we will explore the various types of deck support, including concrete piers, adjustable deck supports, post anchors, and helical piles.

Deck Support Systems: Types and Features

Proper support is crucial to ensure safety and stability when constructing a deck. Several types of decking support systems are available; choosing the right one can make all the difference.

1. Concrete Piers

Concrete piers are a popular option for deck support, providing a solid foundation for the structure. These piers are cylindrical columns made of concrete, designed to support the deck’s weight and distribute it evenly to the ground.

Advantages of Concrete Piers

  • High load-bearing capacity: Concrete piers can support a significant amount of weight, making them suitable for decks of all sizes.
  • Durability: Concrete is highly durable, making piers resistant to wear and tear caused by harsh weather and other environmental factors.
  • Stability: Since piers are embedded deep into the ground, they provide excellent stability to the deck structure.

Disadvantages of Concrete Piers

  • Cost: Concrete piers can be expensive, especially if the deck is large and requires many piers.
  • The installation process for concrete piers can be time-consuming, as each pier needs to be dug and poured separately.
  • Difficult to adjust: Once the concrete has cured, it can be challenging to adjust the height of the piers, making it difficult to level the deck in case of ground settling.

Installation Process for Concrete Piers

  • Excavate holes: The first step in installing concrete piers is to excavate holes at specific intervals based on the deck design and local building codes. The holes should be deep enough to reach stable soil or bedrock.
  • Install forms: Forms are placed into the holes to shape the concrete piers. These forms can be made of plastic, cardboard, or other materials.
  • Pour concrete: Once the forms are in place, concrete is poured into the holes and allowed to cure. The curing process can take several days, depending on the weather and the type of concrete used.
  • Secure post anchors: After the piers have cured, post anchors are installed on top, allowing the deck posts to be secured.

Tips for Maintenance and Repair of Concrete Piers

  • Regular inspection: Inspect the piers for signs of cracking, shifting, or settling. Catching any issues early can prevent more significant problems from developing.
  • Water management: Ensure proper drainage around the piers to prevent water from pooling and causing erosion, which can compromise the integrity of the piers.
  • Repair any damage promptly: If any damage is identified, it should be repaired promptly. Depending on the extent of the damage, repair methods can include patching, sealing, or replacing the affected pier.

2. Adjustable Decking Supports

Adjustable deck supports, also known as pedestal systems, are a relatively new type of deck support that has recently gained popularity. As a result, more and more adjustable deck supports suppliers have entered the market. These systems consist of a decking base supports column and plate that can be adjusted to various heights. They are typically made of plastic, aluminium, or steel.

Advantages of Adjustable Decking Supports

  • Easy to install: Adjustable supports for timber decking or others are relatively easy to install and can be adjusted to the appropriate height during installation.
  • Suitable for uneven terrain: Since these supports can be adjusted, they are ideal for decks built on uneven terrain.
  • Easy to level: If the ground underneath the deck settles, adjustable deck supports can be easily re-levelled to maintain the deck’s stability.

Disadvantages of Adjustable Decking Supports

  • Limited weight-bearing capacity: Adjustable deck supports may not be suitable for larger decks that require significant weight-bearing capacity.
  • Higher cost: Adjustable deck supports can be more expensive than other types of deck supports.

Installation Process for Adjustable Decking Supports

  • Prepare the surface: The first step in installing the deck support adjustable is to prepare the surface where the supports will be installed. This typically involves cleaning and levelling the ground.
  • Install the base plate: Once the surface is prepared, it is installed by anchoring it to the ground or using an adhesive.
  • Install the support column: The support column is attached to the base plate and adjusted to the appropriate height. The column is then secured in place.
  • Repeat the process: The above steps are repeated for each adjustable deck support required for the deck.

Tips for Maintenance and Repair of Adjustable Decking Supports

  • Regular inspection: Inspect the adjustable deck supports regularly for any signs of damage or wear.
  • Cleaning: Clean the supports regularly to prevent debris buildup that could affect their performance.
  • Lubrication: If the adjustable mechanism becomes difficult, lubricate the moving parts with a silicone-based lubricant.
  • Replacement: If any of the components become damaged or worn, they should be replaced immediately to maintain the stability of the deck.

3. Post Anchors

Post anchors are deck support designed to attach a wooden post to a concrete surface. They are typically made of metal and are installed by drilling into the concrete surface and then attaching the post anchor to the concrete using bolts or screws.

Advantages of Post Anchors

  • Strong and durable: Post anchors provide a strong and durable connection between the wooden post and the concrete surface.
  • Suitable for small to medium-sized decks: Post anchors are ideal for small to medium-sized decks that require a secure attachment to a concrete surface.
  • Easy to install: Post anchors are relatively easy to install and do not require any special tools or equipment.

Disadvantages of Post Anchors

  • Limited weight-bearing capacity: Post anchors may not be suitable for larger decks that require significant weight-bearing capacity.
  • Vulnerable to rust: Post anchors made of metal may be vulnerable to rust over time.

Installation Process for Post Anchors

  • Mark the location: The first step in installing post anchors is to mark the location where the post will be installed on the concrete surface.
  • Drill holes: Drill holes into the concrete surface at the marked locations.
  • Attach the post anchor: Attach the post anchor to the concrete surface using bolts or screws.
  • Install the post: Once the post anchor is securely attached to the concrete surface, install the wooden post onto the anchor.

Tips for Maintenance and Repair of Post Anchors

  • Regular inspection: Inspect the post anchors for any signs of rust or damage.
  • Cleaning: Clean the post anchors regularly to prevent debris buildup that could affect their performance.
  • Rust prevention: If the post anchor is made of metal, apply a rust prevention coating to prevent rust from forming.

4. Helical Piles

Helical piles, also known as screw piles, are a type of deck support that consists of a steel shaft with helical plates. The shaft is screwed into the ground using specialised equipment, providing a strong and stable foundation for the deck.

Advantages of Helical Piles

  • High weight-bearing capacity: Helical piles can support large-weight loads and are suitable for larger decks.
  • Suitable for various soil types: Helical piles can be installed in various soil types, including clay, sand, and rocky soil.
  • Minimal disruption to the landscape: Since helical piles are screwed into the ground, they do not require excavation, minimising disruption to the landscape.

Disadvantages of Helical Piles

  • Requires specialised equipment: The installation of helical piles requires specialised equipment, which may increase the installation cost.
  • Limited availability: Helical piles may only be available in some areas, which could make them difficult to obtain.

Installation Process for Helical Piles

  • Soil testing: The first step in installing helical piles is to conduct a soil test to determine the appropriate size and placement of the piles.
  • Screw piles into the ground: The helical piles are screwed into the ground using specialised equipment once the soil test is complete.
  • Install brackets: Once the piles are in place, brackets are installed onto the top of the piles to support the deck.

Tips for Maintenance and Repair of Helical Piles

  • Regular inspection: Inspect the helical piles for any signs of damage or wear.
  • Cleaning: Clean the helical piles regularly to prevent debris buildup that could affect their performance.
  • Replacement: If any of the components become damaged or worn, they should be replaced immediately to maintain the stability of the deck.


Choosing the right deck support system is an essential aspect of deck construction. It not only provides structural integrity but also determines the lifespan and performance of the deck. Each system has advantages and disadvantages, from concrete piers to helical piles to adjustable stirrups for decking, installation process, and maintenance requirements.

Regarding composite decking, the choice of deck support system becomes even more crucial. Composite decking is popular among homeowners because of its durability, low maintenance requirements, and eco-friendliness. However, to ensure the best performance and longevity of composite decking, choosing a reliable and durable support system that can withstand the weight of the decking material and resist rot, rust, or decay is essential.

One advantage of composite decking is that it’s lightweight, which makes it suitable for a wide range of support systems, including adjustable deck supports and post anchors.

Composite decking is also resistant to moisture, which reduces the risk of rot and decay, making it a good fit for concrete piers and helical piles. By carefully considering the type of decking material and the specific needs of your project, you can select the best support system to ensure a safe and long-lasting deck for your outdoor space.