Hot weather working

Hot weather/rapid drying conditions can affect newly applied materials, causing synthetic materials to dry and cementitious materials to ‘pick up’ or stiffen much quicker than normal. Warm, dry conditions with stiff breezes can equally provide rapid drying conditions.

In hot weather, application of both renders and finishes should be carried out in the shade following the sun around the building. We do not recommend applying our products in temperatures over 30°C.  During periods of sustained hot and dry weather, the substrate may need cooling with an even mist spray of clean water before application to avoid retained heat affecting freshly applied mortar.  This should be done in a controlled manner, so as to avoid saturating the substrate as this can induce cracking and/or inhibit the bond of the materials to the walling. This advice is particularly relevant when rendering onto aerated autoclaved blocks.

Cementitious products need to retain water for sufficient time to enable the cement to hydrate fully in order to reach full strength. Rapid drying conditions may therefore leave render materials weak. During hot, rapid drying weather cement based products may need to be actively cured by mist spraying with clean water two times a day for three days after application. This is particularly relevant when working internally. In common with all cementitious mixes, renders will not achieve full strength for approximately 28 days. During this period the finished work is more vulnerable to damage.

Contact us

If you have any questions or would like assistance, please contact our technical team:

Our technical team is available Monday to Friday, 8:30am until 5.00pm.

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