Groundworks and Foundation Options

The foundation is the critical starting point for any oak frame structure, ensuring stability and longevity. At Oak Frames Direct, we offer a variety of foundation options to suit different site conditions and project requirements. Whether you’re building a garage, garden room, or another oak-framed structure, it’s important to choose the right foundation to support your frame. 

Our guide and its related FAQs cover everything from shallow and deep foundations to insulation options, giving you the clarity you need to make informed decisions for your project.

What are Foundations?

Foundations are the structural base that supports a building, transferring its weight to the ground below. They provide stability and ensure the building remains level and secure.

What are the Different Types of Foundations Available?

Foundations are typically divided into two categories: shallow foundations and deep foundations.

What’s the Difference Between Shallow and Deep Foundations?

Shallow foundations are placed near the surface of the ground and are typically used for smaller or lighter structures. Deep foundations, on the other hand, extend deeper into the ground, reaching stronger soil or rock layers, and are used for larger structures or in areas with weak surface soil.

How Do I Know Which Foundation Type is Best for My Project?

The best foundation type for your project depends on several factors, including soil conditions, the size of the building, and any specific requirements from your local building regulations. A Building Control Officer or Groundworker can help determine the most suitable foundation by assessing the soil’s load-bearing capacity and the design of your structure. 

It’s important to consider factors like whether the ground is soft or firm, as well as whether the foundation needs to support heavy loads or provide insulation.

What Types of Foundations are Best for Different Soil Conditions?

The best foundation type depends on the soil’s load-bearing capacity. For stable, firm soils, shallow foundations like strip or pad foundations are typically suitable. For softer or weaker soils, deep foundations like piled foundations or raft foundations may be necessary to reach stronger soil layers and provide adequate support.

Can I Use a Combination of Shallow and Deep Foundations on the Same Project?

Yes, in some cases, a combination of shallow and deep foundations can be used on the same project, depending on the varying conditions of the soil across the site. For example, you might use shallow foundations for the majority of the structure, and piled foundations in specific areas where the soil is weaker. A structural engineer or Building Control Officer can assess and recommend the best approach.

When Should I Choose Pad Foundations for My Project?

Pad foundations are ideal for supporting single columns or posts, making them a great choice for smaller structures or when you have individual points of load, such as for an oak frame garage or garden room. They are typically used when the soil is strong enough to support the load and when only a few support points are needed. 

Pad foundations are simple to install and cost-effective, but they may not be suitable for larger buildings that require more extensive support.

How Do Strip Foundations Work and When are They Necessary?

Strip foundations are continuous strips of concrete that run beneath the walls of a building, providing support along the length of the structure. They work by evenly distributing the weight of the walls onto the ground. 

Strip foundations are necessary when building walls that need a stable base, particularly in areas with firm soil. They are commonly used for oak frame buildings as they offer reliable support for the structure and are ideal for medium to larger-sized buildings.

What are Raft Foundations and When Should They Be Used?

Raft foundations are large, reinforced concrete slabs that spread the load of the building across the entire area of the structure. They are particularly useful on soft or loose soils with low bearing capacity, as they help to distribute the weight evenly. 

Raft foundations are typically used when other foundation types, such as strip foundations, might not provide sufficient support due to the soil’s condition. They require careful design by a structural engineer to ensure they are suitable for the site.

When Would I Need Piled Foundations?

Piled foundations are used when surface soils have low load-bearing capacity and cannot support the weight of the structure. They’re necessary for larger or heavier buildings, or when the ground conditions are poor, such as in areas with loose or soft soil. They provide a strong, stable base by transferring the load to deeper, more reliable soil layers.

What is the Purpose of Saddle Stones, and How Should I Choose the Right One?

Staddle stones are used to elevate posts or beams above the ground, preventing moisture damage and ensuring the stability of the structure. They help distribute the weight of the frame evenly and protect the base of the posts from rot. When choosing the right staddle stone, consider whether you need a flat stone (for use against existing buildings or where garage doors are fitted) or a tapered stone (for general use). 

What is the Difference Between Using a Soleplate at the Finished Floor Level Versus a Dwarf Wall?

A soleplate at finished floor level (FFL) is placed directly on the ground or concrete slab, providing a stable base for the frame. This method is ideal for larger buildings as it allows the frame to be fastened securely and ensures a solid connection to the floor structure.

The dwarf wall method, on the other hand, is often chosen for smaller structures or when additional insulation is needed.

Are There any Planning Permissions or Regulations I Need to be Aware of for Foundations?

Yes, foundations must comply with local building regulations, which may include specific requirements for depth, type, and materials. In some cases, you may also need planning permission if the foundations are part of a larger construction project or if the building is in a conservation area. It’s essential to consult with your Building Control Officer to ensure all regulations are met.

Do I Need to Prepare the Site Before the Foundation Work Begins?

Yes, preparing the site is crucial for foundation work. This may involve clearing the area of debris, vegetation, or existing structures, and ensuring the ground is level and properly compacted. A groundworker or contractor can help assess and prepare the site for the foundation installation process.

Can the Foundations be Adjusted During the Building Process if Needed?

While foundations are typically designed and agreed upon in advance, minor adjustments may be possible during construction if unforeseen issues arise, such as changes in soil conditions or building design. However, significant changes may require additional approvals and design modifications from a structural engineer or Building Control Officer.

Ready to Start Your Oak Frame Project?

Whether you’re building a garage, garden room, or another oak frame structure, our team is here to guide you through every step, from selecting the right foundations to completing your build. Contact us today to get your project started or to speak with one of our experts about your foundation options.am & block. They each have their use in special conditions and advice should always be sought from your Building Control Officer or your Groundworker as to what will be the best and most cost effective foundations for your project.