How Do I Use Post Mix Concrete?

Post Mix Concrete is a versatile, pre-mixed and fast setting concrete product, ideal for both DIY and professional use. In the garden it provides strong foundations for gate posts and fence posts without the need for measuring different materials or a cement mixer. Here's all you need to know about Post Mix.

What is Post Mix Concrete? 

Post Mix Concrete is a ready-mixed concrete, a finely blended, kiln-dried mixture of cement and ballast. It's sometimes referred to as Postcrete, Ready Mix or Postmix and is specifically designed for setting timber, concrete or metal fence posts. It's also ideal for smaller jobs around the garden where you need to fix objects, such as washing lines or children's play equipment.

How do I use Post Mix Concrete?

Using Post Mix is incredibly simple, and full instructions are printed on each bag. 

• Dig a hole
• Place the post into the hole, then half fill the hole with water
• Pour the dry bag(s) of concrete directly into the hole, until the mix is above the level of the water. You may need to add a little more water at this stage if any dry powder is still visible
• Agitate the mixture with a stick to ensure that any air bubbles are released
• Adjust the position of the post and allow to set

Top tips - if your ground has very poor drainage, a small layer of shingle placed into the hole before the post will assist drainage. It's recommended to wear gloves and a face mask when applying the dry Post Mix as concrete dust is an irritant. The level of your concrete should be slightly above ground level to avoid water collecting at the base of the post.

How long does Post Mix take to set?

The main advantage of using Post Mix Concrete is its setting time. The concrete will begin to set within minutes of adding water, and will be firm in between 10 and 20 minutes. This is ideal when setting posts as the post can still be adjusted to ensure it is straight during this time, but will be secure once the mix has firmed.

In comparison, regular mixed concrete can take several hours if not days to reach the same consistency.

It's recommended to leave the Post Mix for at least 4 hours before applying stress to the post, such as fitting fence panels. 

Is Post Mix Concrete expensive?

Mixing your own concrete will always be more cost effective than using Post Mix Concrete when you just measure the cost of the materials, however Post Mix saves costs in other ways:

• no time and effort spent on measuring and mixing
• no cost of a cement mixer
• buy only what you need - our Post Mix Concrete is supplied in handy 20kg water-resistant bags
• shorter setting time equals a shorter job 

How much Post Mix do I need for a fence post?

The exact amount of Post Mix Concrete needed will vary depending on the width and depth of the hole, but as a general rule you'll need about one and a third bags for a standard fence post.

A gate post, which works harder than a fence post due to the movement of the gate, may require three or four bags.

Because our Post Mix Concrete is supplied in water-resistant bags, any excess can be stored and used at a later date.

Can I mix Post Mix in a bucket?

In a word, no. Post Mix Concrete is very fast setting, and is designed to be mixed with water in-situ. Mixing in a bucket runs the risk of ruining a good bucket and any tools you are using.

Ask the fencing experts

For further advice about your fencing project don’t hesitate to speak to our fencing experts at your local AVS Fencing & Landscaping Supplies branch. Our range of Post Mix Concrete and high quality fencing materials are all available either to click and collect from your local AVS Branch or for home delivery within our AVS Branch delivery area.