How to level external concrete?

[Bolton]

Hi, I have a form concrete external structure. It’s a sunken fire pit however I need to level the concrete. Can self leveling concrete be used outside and how easy or hard is it to do ?

It would need to be around 100mm in depth. 

[EricL]

Hello @Bolton 

Most of the self-levelling cements will only go up to a maximum of 25mm as they are often used for surface adjustments. But if you need it at 100mm in depth, I recommend using Easy Mix 20kg Concrete. 

I propose creating formwork with your desired level built in. In this manner when you start doing the finish on the surface of the concrete there will be no need to use the self-leveller.

However, please keep in mind that if the surface is too level water will stand and gather in pools on the surface, I therefore advise putting in a slight fall so that rainwater will slide off the surface. I recommend using a builder's line as a guide and a spirit level to double check the level of the concrete.

Here is a handy step-by-step guide: How to pour a concrete slab (the techniques used are applicable to your project)

If you have any other questions we can help with, please let us know.

Eric

[Bolton]

Thank you Eric, it already has form concrete poured and it’s dug into the ground already however the easy mix concrete might be the way to go then the tiler can create a slop towards the drain. 

[Bolton]

Hi, I have an issue with a sunken firepit. The guy that built it put a drain in the middle and didn’t link it to anything so we have had to put a new drain in. Its raised the new drain point by 100mm (top of drain). The obvious way is to concrete the base higher and put my drain grate in but the concreting quotes are so expensive.

Any ideas ?

   

[MitchellMc]

Hi @Bolton,

So, are one of the two drains connected, or are none of them? If so, which drain will you be using that needs to be raised? Do you need to raise the height by the full 100mm? What issue are you trying to resolve here, and what's the end goal? I trust that once our members have a better understanding of what you're trying to achieve, they'll be able to provide solutions.

Mitchell

[Bolton]

I think I’ve figured it out. The side drain is connected. I’m going to run screed to create a small slope then tile towards the drain. I’ve decided to use a drain cover on the wall rather than use a drain grate. It’s only for rainfall. Hopefully this works. 

[EricL]

Hello @Bolton 

If you are screeding towards the drain in the wall, I suggest using a builder's line to make sure your screed is going towards the waste. Make sure to double check its slope using a spirit level. 

If you need further assistance, please let us know.

Eric