Should I lay waterproofing membrane under engineered timber flooring in laundry and toilet?

[michelle0911]

Hello, I want to run my engineered timber flooring into my laundry and toilet. The base is half yellow tongue /half pine floorboards.  The yellow tongue is new replacing the water damaged section of both rooms due to previous owners poor plumbing.  Can and should I have a waterproofing membrane applied before the new flooring goes down?  Thanks Michelle 

[JacobZ]

Hi @michelle0911,

A warm welcome to the Bunnings Workshop community, it is fantastic to have you with us.

Adding a waterproofing membrane would certainly be worthwhile to prevent further water damage from occurring in the laundry and toilet. 

There are waterproofing products such as Crommelin 15kg Pro-500 Undertile Waterproofing Membrane that can be applied over timber.

With this being said, as waterproofing is a licenced industry, it is likely best to contact a waterproofer for assistance with this project. While you are not building a new home where the membrane needs to be certified to pass inspection, it is still likely worth having a professional assist you for your peace of mind.

Let me know if you have any further questions.

Jacob

[michelle0911]

Thanks so much Jacob.  I will follow up with a waterproofer