How to waterproof a MDF bathroom vanity?

ram7

We have had a new MDF vanity installed in our bathroom. The vanity top just covers the MDF cabinet beneath it, so there is a risk that water will frequently come in contact with the cabinet over time and I am scared that over time water damage can occur. Is there a waterproof sealant or clear paint that I can apply on the MSF cabinet especially around the edges to make it water resistant? 

JacobZ

Hi @ram7,

Welcome to the Bunnings Workshop community, it is fantastic to have you with us.

Typically, MDF bathroom vanities will use MR (moisture-resistant) MDF, which is made using a special water-resistant resin and a water-repellent wax in its manufacturing, making it more durable and resistant to humidity and accidental wetting. With this being said, any additional steps you can take to protect it would certainly be worthwhile.

The main suggestion I have is to ensure that the seam between the underside of the vanity top and the top of the vanity is sealed with silicone such as this Selleys Wet Area Waterproof Silicone Sealant, in a colour of your choosing.

The coated faces of the vanity are not particularly risky; however, the cut edge at the top of the vanity, which sits under the top, will be. Applying silicone to this seam will help prevent water from getting up under the basin top, where it can sit on this cut edge, soak in and cause issues.

Check out How To Apply Bathroom Sealant and How To Silicone a Gap for some guidance on the application process.

Let me know what you think and if you have further questions, please don't hesitate to ask.

Jacob