Modern Methods of Construction (or MMC) are challenging the dominance of traditional brick and block structures. Styles of build are constantly being redefined with the creation of new production techniques designed with speed, ease of assembly, reduction of material use and wastage in mind.
Growth of panel construction
The current direction for MMC solutions is predominantly a frame and panel scheme, which when used in conjunction with a render system will create a durable weather defensive shield with various aesthetic options available, including modern render finishes or the traditional styling of a brick slip.
In this article, we look at the considerations that need to be made as a renderer to ensure installation is correct and best practice is being followed before applying the final finish.
Which boards can I render onto?
The boards used in a frame and panel system have many different names but may be referred to as:
Render carrier board
Exterior cement board
External render board
Cement fibre board
Concrete particle (CP) board
Substrate board
Sheathing board
Whilst they should all do the job in practice, testing and certification is crucial to ensure that a board will stand the test of time, be fully guaranteed and carry the accreditations required by insurance companies.
Why is it necessary to use a certified board?
In all construction materials, some products will be inferior to others, with render boards needing to hit a very fine line between being robust to offer the building a solid substrate and being flexible enough to absorb movement and avoid the render cracking. Some boards can include high levels of wood particles to reduce the cost and weight, and whilst cheaper, they will be more prone to movement and swelling which can crack and delaminate render.
At Weber we test render boards in line with BBA Certification requirements. The boards will have been thoroughly assessed for their durability, longevity, reaction to fire, freeze / thaw cycles, moisture and impact resistance - all in conjunction with our render systems.
The following boards have been fully tested for compatibility with the weberend MT system with various finishes and hold a BBA Certificate
When using a render board we recommend you contact the manufacturer of the board to establish the specification required for its use, including areas such as:
Fixing pattern – should it be offset / broken bond?
Fixings required – is a specific fixing required for the board?
Fixing centres – what is required to achieve the necessary wind load requirements?
Spacing – what gap is required around the perimeter of the board edge?
Finishing - is sealant or tape between boards required?
Suitability – what is the maximum height that the board can be used?
Contact us
If you have any questions or would like assistance, please contact our technical team: