I am waterproofing my laundry before tiling and I've bought crommelin hi_preformance primer for non_porous surfaces but there's no detail as to how to use it prior to applying the water proof membrain, any advise would be appreciated
Welcome to the Bunnings Workshop community @gorbulusboffin and thanks for joining the discussion.
I am sure that @MitchellMc will have some advice for you when he's back tomorrow. In the meantime, here are some helpful step-by-step D.I.Y. videos on How to waterproof your bathroom floor and How to waterproof a shower recess. Could you share a few more details on what type surface material you are waterproofing so we can help with advice on how best to apply this product?
Here are the full instructions on water-proofing using Crommelin products. I'll include the technical data sheet for Crommelin hi-performance primer for non-porous surfaces. Within it, you'll find an application section. You basically need to apply it with a brush or roller as per the recommended coverage rate and then wait one hour before over-coating with your water-proofing membrane.
Please let me know if you have further questions or run into difficulties.