Rendering onto Pebbledash

Before the use of polymer cements in the 1990’s a pebble dashed finish could look tired and dull after several decades. Avant Coatings Ltd is often called upon to rejuvenate such a property. With many coatings and rendering systems available we can find the right solution at an affordable price. It is possible to render onto pebbledash providing the substrate is in a good condition and the backing render is sound and solid.

There are two main types of system available to render onto pebbledash. The first is a common type of render such as a lime render or polymer render which will produce a flat or scraped finish, the second is an acrylic or resin (or enamel) render, which will blend a certain level of the pebbles or spar out but still leave a nice textured finish. Both systems dramatically improve the look of any building and cover over the old tired pebbledash

Hydraulic Lime or Polymer Render onto Pebbledash

The loose pebbles or spar first needs to be removed by water jet method with the use of a strong shovel. Any minor repair should then be carried out to the substrate before a render is applied. When rendering onto pebbledash, careful consideration needs to be taken when selecting the rendering materials, older pebbledash will be lime based, a cement or polymer cement based render is not suitable to render over a lime based mortar due to the rigid, impermeable nature of the cement. Only Hydraulic Lime based products should be used to render over lime based pebbledash.

This is not to say Polymer rendering products are not good products... they are very good, but simply unsuitable for rendering over lime based materials and structures.

Acrylic or Resin (Enamel) Render over Pebbledash

An alternative and less intrusive method of rendering over pebbledash is an acrylic or resin (enamel) render coat. During the initial survey the decision would be made as to whether an acrylic or resin render coat would be most suited to the building. This analysis would be based on the walls age, type, condition and exposure to bad weather. The application of a lime wash or cement wash (often called a slush coat or bagging coat) is needed to stabilise the wall and provide an ideal surface to apply. The acrylic or resin render is available in many colours and is particularly desirable if you are wishing to cover up repair work or an alteration to an exterior wall. It often works out cheaper than lime or polymer rendering and can look just as good if not better.