Why does a cement render coated with a conventional paint system crack?
Traditionally “cement render” means site mixed sand and cement (bulk materials mixed on site) but increasingly these days includes various supplier pre-packed bagged cement renders. Some suppliers and/or builders and/or applicators may support cement renders as finishing systems in their own right for reasons of their own (generally economics). Some add a layer of confusion with terms like “Acrylic Render” – referring to very small amounts of acrylic sometimes added to pre-packaged cement renders as additives, which assist application and curing only. Pre-packaged bagged supplied cement renders offer some advantages over site mixed render in terms of easy handling and product consistency of mix formula (ie. vs uncontrolled site mixed render), but essentially they are still low cost, bulk sand & cement products primarily designed for use as a surface leveling building materials. Neither a site mixed render nor a pre-packed render are acrylic, nor are they waterproof, nor flexible in any
