Our DIY series is this week showing you how to create a concrete fireplace hearth. The step-by-step guide comes thanks to Olivia Likosso, whose renovations of an ex-council London Flat we have been closely following at @renovating_cheznous.

Olivia: My boyfriend, Robert, and I bought our London flat a little bit over a year ago and have been slowly renovating it ever since. We’ve never done anything like this before, so it has been a learning opportunity for both of us. The flat really needed some serious TLC; we needed to completely gut the place and unfortunately found a lot of botched jobs along the way, which meant more money and time needed to go into it. For a long time, it felt like we were getting nowhere. 

Renovating can be very stressful, but also a lot of fun. We are both obsessed with fireplaces and, fortunately, the flat came with two but they needed revamping, so we decided to build out one of them and create a concrete hearth from scratch.

Here is how we achieved it:

Tools
Power drill
Mask 
Goggles
Tape measure
Pencil
Circular saw
Fog tape
Electric hand mixer
Trowel
Spirit level
Plastic buckets

Materials
25kg bag of sand (we used four and a half bags, but it all depends on the thickness you want)
Concrete
Wooden timber for the frame
Screws for attaching the timber 
Clear filler
L-Brackets
Plastic sheet
Thin metal rebar

Firstly, start by outlining with tape where you would like the hearth to go – this will be used as a template. After you’ve done so you should cut the wooden timber to size and drill it in place using L-brackets to secure it into the floor, so you can use it as a mould when pouring the concrete mix.

Once the timber has been secured, use clear filler to fill any gaps to prevent anything from leaking. Make sure it’s dry before you start pouring the mixture. For additional protection, prepare the exterior flooring with a plastic sheet and use engineer bricks against it to support the timber.

Follow the mixing instructions on the bags of your sand and concrete – our ratio was 3:1. Pour the mixture of sand, concrete and water into the bucket and use an electric hand mixer to mix it together. You want to make sure the mixture’s consistency is easy enough to pour and to spread evenly, so start with a bit of water and add more if needed.

Pour the cement mixture into the wooden mould that’s been created. After the first couple of buckets have been poured, use a trowel to spread the concrete mix as flat and level as you can. When you reach mid-way through, lay the measured-out metal rebar onto the concrete, the aim of which is to strengthen the concrete.

Continue to pour the concrete mixture until it is level and flush with the timber (or your desired height). Using a trowel and spirit level will be necessary for the perfect finish. Allow to completely dry for a week before removing the timber frame. If you want a smoother finish go over the top while the concrete is wet with a trowel.

To finish off the look, you can tile up the back of the fireplace, we used brick slips tiles.