It doesn’t come around very often, or stay for very long, but when it does the British summer time is glorious. Most people will slide into a pair of shorts and either take a trip to the beach or a pub garden. That’s fine for the weekend but through the week you’ve got to earn money spraying render on the walls. Render is a cement based product which means warm conditions can affect the way it dries or picks up. Please read on for some general industry information when it comes to machine applying render in the summer months.
When the temperature increases we are also greeted by rapid drying conditions. This can have major effects on newly applied materials, causing synthetic materials to dry out and cementitious materials to stiffen or pick up much quicker than normal. These rapid drying conditions can be caused by hot, dry or blustery conditions. When spraying render in hot weather you should look to apply to the side of the building in the shade and then follow the shade around the building.
Cement based products, such as render, need to hold water for enough time to enable the cement to hydrate fully and reach full strength. Rapid drying conditions may leave most render materials weak. With this in mind if you cannot machine apply your render in the shade you may need to ‘cool’ the substrate/wall you are spraying on to. This can be achieved by spraying an even mist of clean water before application. Please remember this should be done in a controlled manner. You must avoid saturating the substrate as this can cause cracking. This advice is very important to remember especially when rendering onto block work.
When using a rendering machine to mix and spray your render you will also need to make sure you are using a cold water supply to mix with. It would be a good idea to let hot water run out of hoses before using them as hot water makes render go off faster. If using a water butt or buckets of water make sure the water is not sat in the tub for too long as it will warm up. We have also heard of people adding a fraction more (0.5 litres) water to each mix, this compensates for the water that could evaporate due to heat. Another top tip when spraying machines with rubber hoses is to make sure you do not leave render in the delivery hoses for an extended amount of time. This can lead to material going off and blocking your rotor/stator, delivery hoses and spray gun. One final thing to consider when using a diesel rendering machine is to make sure your engine coolant is topped up. This, along with switching the machine off when not in use, will allow your machines to cool off.
If you are in any doubt when applying your render it is best to seek advice from the render manufacturer. For more information on hiring or purchasing rendering machines please visit our website or call 01494 715472.