NHBC has released new technical guidelines regarding best practice for the application of render. This guidance was given as part of the publication of the NHBC Standards 2017. These Standards came in to force at the start of this year.

As part of Chapter 6.11 of the NHBC publication the ‘Render’ section is thought to become a key element of NHBC’s on-going campaign reduce the number of reported defects on external walls. Due to the nature of the product. Render can be exposed to varying degrees of weather types and severities. This means that after a relatively short period of time the durability of the product will be tested. Therefore, the National House Building Council is thought to have provided technical guidance for the rendering of a house that will help towards reducing the damage inflicted by the weather.

In order to explain the reasons behind creating this new chapter, Paul Cribbens the NHBC Standards Manager suggests that it is important to make sure that the rendering of a property is done properly because any shortcuts and poor design can become apparent very quickly. Whereas if the rendering was properly considered and carried out, there would be a reduction in the level of damage. In order to reduce the chances of preventable damage, the chapter in NHBC Standards 2017 includes some specific guidance to support the building designer. Pieces of the new guidance includes movement joints should be continuous through the render and the background in order to make sure the building is made weather tight with the appropriate seal. It Standards also state that joints should be positioned so that they do not pass through rigid wall components like lintels or bed joint reinforcement. Other pieces of guidance include making sure that the accommodation of the movement to the rendered parts of the home is considered at the design stage.