Acrylic Render v Cement Render

Ok. So lets talk about the differences between acrylic and cement render, as there seems to be a lot of confusion surrounding the two. Firstly, you must understand what each one actually is and the purpose it serves.

Cement Render.

Many people wrongly call pre-mixed dry render in bags, acrylic render. It is sand and cement with additives, such as dry acrylic binding agents, amongst other ingredients.  This doesn’t make it acrylic render. It makes it cement based render. The main ingredients are sand and cement. The main advantage that it has over site mixed sand and cement, is its quality of ingredients.  Bag render is produced in a factory, where the sand is washed, graded and mixed evenly in the correct ratios with the other ingredients.  This makes it consistent in nature and affords the manufacturer the ability to warrant it against contamination. Site mixed sand and cement has the risk of unpackaged sand (the main ingredient) meeting with contaminates. Both bagged, and site mixed renders can serve as a base coat for trowel on textures (acrylic render), or can be finished and overcoated with paints and membranes.

Acrylic Render

Acrylic render can better be thought of as trowel on paint. Essentially it is a thick, paint like coating with aggregate (sand) added to it. It’s used in conjunction with either bag or site mix cement render, as a coating over the cement render. It is not possible to use pure acrylic render as a stand alone coating over brick or block. The maximum thickness can not be more than a couple of millimetres. The coating can be coloured with tints and used as a finished coat in lieu of paint, however in almost all cases it requires some kind of clear sealer to protect it. This is what most people are thinking of when they think coloured render.