A Handy Guide to Laying a Concrete Slab

A Handy Guide to Laying a Concrete Slab

‘How to lay a concrete slab’ is one of the most popular questions our customers ask our team of concreters on the Gold Coast. While it’s not something any regular homeowner can do, the job is not too hard either. Still, we recommend that you leave this task to experienced professionals as it is very easy to botch up. So without further ado, check out our handy guide below.

Step 1: Have all the materials ready beforehand

Having all the materials and tools ready before we get to work is essential when laying a concrete slab. Here are some of the things our crew from Concreters Gold Coast use to do that.

The very first thing we need, of course, are several bags of cement. We’ll also need some water, some aggregates, and last but not least, bags of sand. To ensure that the slab won’t crack easily, we make sure that the ratio of each material is correct. Other essentials include several pieces of timber rails for the frame, some timber stakes, and brightly coloured string or mason line.

We’ll also need a durable shovel for incorporating all the materials, as well as a steel screed. Different types of trowels, floats, and other similar tools are also necessary for this task. To make sure that our concrete slab is accurate, straight, and true, we’ll need a tape measure, as well as a mason’s level. 

Don’t forget that wheelbarrow for mixing cement, water, aggregates, and sand. Our concreters on the Gold Coast already have a concrete mixer ready for each job, but if you’re planning to give it a go, then it’s best to borrow or hire one to make mixing concrete easier.

Step 2: Lay out the formwork

Next, the concreter will set up the area where you want the slab laid out. The labourer will first mark the area using rolls of mason line. Using a mattock and shovel, your concreter will then dig up and remove around 100 millimetres of topsoil from the chosen area. The ground will then be flattened and compressed before the timber frame is set up and the stakes pounded into the ground to support them.

Step 3: Mix it

This is one of the most important steps as this could literally make or break the concrete slab. Following the correct ratio, our concreter will mix cement, sand, and aggregates in a wheelbarrow or a large concrete mixer. We make sure that everything is incorporated thoroughly before we add water, and we will check periodically to see if the consistency is just right. If you’re laying the slab yourself, be careful when adding water as too much can make the end result brittle and prone to spalling.

Cement Mixing

Step 4: It's showtime (or it's time to pour the mixture)

Next, we’ll pour the mixture onto the area. You can also apply the mixture onto the ground using a hand trowel or a shovel if you’re doing it yourself, but this is only recommended if you’re working on a relatively small area. When applying concrete, make sure that it reaches a little above the timber. Scrape off any excess to make sure that it is compact and that the surface is 100% level.

Our crew will let the mixture’s excess water “bleed” or seep to the top for several hours before we finally apply the finishing touches. You can have a completely smooth and flat finish, or you can have our concreters on the Gold Coast brush or expose the aggregates to give it some interesting texture.

Step 5: Let it cure

house exterior with brick wall

Sprinkle a bit of water on the surface every day for seven days before allowing it to dry completely.

So there you have it, how to lay a concrete slab. Make sure to check out the other blog posts to learn more about concrete and the things you can accomplish with it.