Working with Concrete in Hot Weather – Some Top Tips

Many home DIY projects take place either in the summer or over a Bank Holiday weekend when the days are longer, the weather is warmer and homeowners are likely to have some time off work. However, if you are using any concrete, then very high temperatures have the potential to create some issues with the admixture.

Here Madmix, who supply domestic concrete across Cambridgeshire, provide some top tips which should ensure everything goes smoothly and the quality of your concrete is unaffected.

The Application of Science

Water is one of the principal ingredients of concrete (along with cement and ground granulated blast furnace slag, or GGBS for short). When these three elements are mixed together, the hydration process begins. This is where the concrete begins to set and develop its strength.

Concrete has ‘set’ if it can absorb pressure without suffering any damage – so if you walk on it, you won’t leave a footprint behind. In hot weather, the setting time is greatly reduced, meaning that you don’t have as long to smooth it out and finish it. And the faster the concrete sets, the more likely it is to crack in the future.

It’s not just the concrete setting time which could be an issue in hot weather, but the curing process as well. All admixtures need to go through this process to reach their maximum strength, and to do so evenly, the concrete needs to maintain its moisture. Evaporation should be avoided, as premature curing will weaken the concrete.

What Can You Do?

There are a number of steps you can take to minimise the effects of hot weather. These include:

Prepare the Site – if you are expecting a delivery of ready-mix concrete, make sure the vehicle can reach the site easily. Make sure any vehicles won’t impede access to homes or driveways, including your neighbours’. Also, make sure to clear away any debris and unwanted items from the site itself. If the pour site is relatively inaccessible, then it may be worth using a pumpable admixture and hiring a pump.

Madmix supply pumpable concrete to customers as far afield as Royston, Newmarket, St Ives and St Neots and we recommend Boxfast Plant Concrete Pumping Specialists for the actual pumping – their contact details can be found here.

Keep Everything Moist – before your concrete arrives, you can use water to dampen any sub-base as well as the timber framework. You should also erect some sunshades and screens to keep the work area out of direct sunlight. Keep all equipment in the shade for as long as possible. All of this helps to keep the site cool, aiding the hydration process during the pour. It will also ensure that the concrete is properly cured.

Choose the Right Delivery Time – generally, the temperature peaks at around 12noon and in the early afternoon, so try to avoid these times if you are working on a concrete project.

The early morning is probably the best time for a delivery. At Madmix, the slots we offer are Monday to Friday – early morning, next day or sometimes same-day delivery service, subject to the availability of mixers – or Saturday morning deliveries (for a small premium).

Look After Yourself – it’s not just concrete which is affected by hot weather; humans are as well. So, if you are working on a domestic concrete project and the temperatures are soaring, make sure you apply plenty of sun cream, wear comfortable, loose-fitting clothing and make sure there’s a regular supply of cold drinks at hand. You should also use a wheelbarrow rather than try to carry anything yourself.

Buy Accredited Concrete – you have the confidence in knowing that all of your concrete is of a consistently high quality, and less likely to suffer from any of the problems listed above. Madmix has received the BSI kitemark, showing that our assured concrete has been tested and fully meets the BS EN 206 and BS 8500-2 standards. Our Quality Management System has been awarded ISO 9001 accreditation.

Domestic Concrete in Cambridgeshire from Madmix

If you would like to know any more about the different types of admixtures we can offer for domestic concrete projects, follow this link. You can also call us on 01954 212212, or email us at info@madmix.co.uk, and we will be happy to give advice on what you need.