Pier Foundations: A Comprehensive Guide for Construction Projects

When planning the foundation for a new structure, whether it's a home, deck, or cottage, understanding your options is crucial. One of the most versatile and cost-effective solutions is the pier foundation. Pier foundations are widely used for various projects due to their adaptability, affordability, and effectiveness in supporting structures, even in challenging environments like flood zones or rocky terrain. In this guide, we'll cover everything you need to know about pier foundations, including their types, benefits, disadvantages, and common applications.

What is a Pier Foundation?

A pier foundation is a structural foundation composed of vertical columns, or piers, installed deep into the ground to support the weight of a building or structure. These piers are typically made of materials such as concrete blocks, reinforced concrete, or steel. At Quality Homes & Renovations, we primarily use reinforced concrete piers formed with sonotube forms or Postech helical screw piles for durability and strength.

When Should You Use a Pier Foundation?

Pier foundations are commonly used in situations where traditional foundations, such as full basements or slabs, are either unnecessary or impractical. Here are a few scenarios where pier foundations are ideal:

• Decks and Porches: If you've ever seen a deck attached to a home, you've likely observed pier foundations in action. These piers provide stable, long-lasting support for outdoor structures like decks, carports, and porches.

• Cottages and Homes: Pier foundations are also used for residential structures, especially in areas where basements are either impractical or not desired. After severe flooding in Renfrew County in 2017 and 2019, Quality Homes & Renovations helped homeowners raise their properties on new pier foundations to prevent future flood damage.

• Remote Locations: For difficult-to-access sites, like water-access-only properties, pier foundations—specifically Postech screw piles—can be a game-changer. In 2024, we constructed a cottage on Aylen Lake, where all materials were transported by barge, and screw piles were the only feasible option for the foundation.

Concrete Pier Foundations

Concrete pier foundations are a traditional method that involves pouring reinforced concrete into cylindrical cardboard forms, known as sonotubes, which sit on a larger reinforced concrete footing. The sonotubes are braced in position, filled with concrete, and then removed once the concrete has set, leaving sturdy piers that can support a variety of structures.

Advantages of Concrete Pier Foundations:

• Low Material Costs: The sonotube forms are inexpensive, and rebar requirements are minimal, making this an affordable option.
• No Additional Engineering Requirements: The construction details are standard and included in the Ontario Building Code, eliminating the need for specialized engineering oversight.

Disadvantages of Concrete Pier Foundations:

• Site Disturbance: Significant excavation is required to properly place the forms. While the use of a post-hole auger can reduce the disturbance, machinery is still required for installation.
• Longer Installation Time: The piers cannot be built on immediately; it takes several days for the concrete to set before construction can continue.
• Concrete Access Issues: Access to the site can be challenging if a concrete mixer or pump truck cannot reach the piers directly. In such cases, wheelbarrowing or mixing concrete on-site can add time and labor costs.

At Quality Homes & Renovations, we typically recommend poured concrete piers for new home construction, where site access and excavation are already part of the project. In these cases, pouring the piers at the same time as the foundation can be cost-effective and efficient.

Postech Screw Pile Pier Foundations

Postech screw piles are an innovative alternative to traditional concrete piers, especially for smaller projects like decks or for sites with difficult access. Made from galvanized steel with an auger blade at one end, these piles are mechanically screwed into the ground using an excavator fitted with a special attachment. The pile’s depth and strength are measured by torque, which is monitored during installation to ensure the pile reaches the desired depth and stability.

Advantages of Postech Screw Piles:

• Minimal Site Disturbance: Screw piles can be installed with very little damage to the surrounding area. The small excavators used in the installation can fit through narrow spaces, and any landscaping disruption is minimal.
• Quick Installation: Once the layout is set, the piles can be installed rapidly, even in difficult conditions. Construction can begin immediately after installation, unlike concrete piers, which require curing time.
• Lower Labor Costs: Fewer crew members are needed to install screw piles, which can help reduce labor costs.

Disadvantages of Postech Screw Piles:

• Higher Material Costs: While the materials are more expensive than traditional concrete piers, this cost is typically offset by the savings in labor and installation time.

At Quality Homes & Renovations, we trust Postech screw piles so much that part of our own office rests on them. They provide an efficient, reliable solution, particularly for projects where minimizing site disruption is a priority.

Pros and Cons of Pier Foundations

When would you use a pier foundation? For a deck or carport, it is the obvious choice. For a cottage or addition to your home, if a basement is required then the advantages below can help you decide.

• Cost-Effective: Pier foundations are the least expensive option and ideal when a basement isn’t necessary.
• Minimal Site Impact: Compared to other foundation types, pier foundations cause less disturbance to the site, which can be especially important when working on an existing home with landscaping or areas with difficult access.
• Flood Protection: For homes and cottages in flood-prone regions, pier foundations provide essential elevation above rising water levels.
• Flexibility: Whether you’re building a deck, carport, cottage, or even a full home, pier foundations can be customized to suit a wide range of applications.

Is a Pier Foundation Right for Your Project?

Pier foundations are a versatile, cost-effective, and durable solution for many building projects, from decks and porches to cottages and home additions. Whether you opt for traditional concrete piers or modern Postech screw piles, Quality Homes & Renovations can help you determine the best foundation for your specific needs. Contact us today to learn more about how a pier foundation could be the perfect fit for your next project.