Structural floor boards for timber joists and their weather resistance

Consideration

When considering how long structural floor boards can be left exposed on site, it’s important to consider the functional requirements, which state:

• All materials should be stored, installed and protected correctly in a manner that will not cause damage or deterioration of the product.
• All materials, products and building systems shall be appropriately tested and approved for their intended purpose.

With this in mind, structural floor boards should be stored, installed and protected as per the manufacturer’s instructions. However, as structural floor boards are built in as the work proceeds they may be left exposed to the elements and they will be subjected to various issues, especially during prolonged periods of precipitation.

Answer

For warranty purposes, structural floor boards for timber joists that are to be installed as the building proceeds and left exposed must have a third party product approval certificate which covers weather resistance for the period of time the boards are to be left exposed on site.

Any boards that are left exposed beyond the period stated in the third party approval certificate should be replaced.