Bolt Down vs Concrete-In Post Supports

If you’re planning a new fence, pergola, garden structure or timber framework, choosing the right post support is one of the most important decisions you’ll make. The two most popular options are bolt down post supports and concrete-in post supports.

But which one is right for your project?

In this guide, we’ll explain the differences, advantages, disadvantages and the best applications for each type of support.

What Is a Bolt Down Post Support?

A bolt down post support is designed to be fixed directly onto an existing concrete base, patio, decking frame or other solid surface.

The support is anchored using expansion bolts or concrete fixings, creating a secure connection without the need for digging holes.

Bolt down supports are commonly used for:

• • Pergolas

• • Garden structures

• • Decking posts

• • Fence posts installed on concrete

• • Carports

• • Timber canopies

Benefits of Bolt Down Post Supports

✓ Fast installation

✓ No digging required

✓ Ideal for existing concrete surfaces

✓ Easier replacement of damaged timber posts

✓ Keeps timber elevated above ground moisture

When to Choose Bolt Down Supports

Choose a bolt down support if:

• • You already have a concrete slab or patio.

• • You are building a pergola on paving.

• • You need a neat and professional finish.

• • Ground excavation is not possible.

Recommended Bolt Down Supports

Our range includes heavy-duty galvanised and stainless steel bolt down post supports suitable for fencing, pergolas and timber structures.

Browse our Bolt Down Post Supports category.

What Is a Concrete-In Post Support?

A concrete-in post support is installed directly into fresh concrete below ground level.

Instead of fixing to an existing slab, the anchor becomes part of the concrete foundation itself.

Concrete-in supports are commonly used for:

• • Fence installations

• • Heavy pergolas

• • Garden rooms

• • Structural timber frames

• • Gate posts

Benefits of Concrete-In Supports

✓ Exceptional strength

✓ High resistance to movement

✓ Ideal for soft ground

✓ Suitable for larger structures

✓ Long-term durability

When to Choose Concrete-In Supports

Choose a concrete-in support if:

• • You are installing a new fence line.

• • There is no existing concrete base.

• • You need maximum stability.

• • The structure will carry significant weight.

Recommended Concrete-In Supports

Our galvanised concrete-in supports are designed for demanding outdoor conditions and provide a secure foundation for timber posts.

Browse our Concrete-In Post Supports category.

Bolt Down vs Concrete-In: Quick Comparison

Feature	Bolt Down	Concrete-In
Installation Speed	Excellent	Moderate
Requires Concrete Base	Yes	No
Strength	Very Good	Excellent
Suitable for Pergolas	Excellent	Excellent
Suitable for Fencing	Good	Excellent
Easy Replacement	Excellent	Moderate
Ground Excavation	No	Yes

Best Post Support for a Pergola

One of the most common questions we hear is:

“What is the best post support for a pergola?”

If your pergola is being installed on an existing patio or concrete base, bolt down supports are usually the most practical solution.

If you’re building a large freestanding pergola directly on soil, concrete-in supports often provide the highest level of stability.

How to Fix Fence Posts to Concrete

Many homeowners search for “how to fix fence posts to concrete”.

The simplest method is to use a bolt down post support fixed with appropriate concrete anchors.

This method keeps the timber clear of standing water while providing a strong mechanical connection to the concrete base.

For larger fence projects installed directly into the ground, concrete-in supports may be the preferred option.

Galvanised or Stainless Steel?

The choice of material is equally important.

Galvanised Post Supports

Galvanised steel provides excellent corrosion resistance and is the most popular option for:

• • Garden fencing

• • Pergolas

• • Decking

• • General outdoor projects

Stainless Steel Post Supports

Stainless steel supports offer superior corrosion resistance and are ideal for:

• • Coastal locations

• • Premium landscaping projects

• • Architectural timber structures

• • Long-term installations

Final Thoughts

Whether you choose a bolt down post support or a concrete-in support depends largely on the installation surface and the type of structure you’re building.

For existing concrete bases and patios, bolt down supports offer speed, convenience and excellent performance.

For new installations in soil where maximum strength is required, concrete-in supports remain the preferred solution.

At ADNA Components, we supply a wide range of galvanised and stainless steel post supports for fencing, pergolas, decking and timber construction projects.

Explore our post support range to find the ideal solution for your next project.