Home > categories > Construction & Real Estate > Cement Boards > Is GAF TOPCOAT Membrane a good idea to use on my wetroom bathroom walls as a waterproofer over cement board?
Question:

Is GAF TOPCOAT Membrane a good idea to use on my wetroom bathroom walls as a waterproofer over cement board?

I came into many buckets of GAF TOPCOAT liquid which says it can be sprayed onto a roof or rolled on. I've only found one other idea for the walls in my wet room/shower area which is flexcement that is waterproof. Is it a good idea to try this or not. Really don't want to mess it up after putting much money into the walls as is. Here is the site that describes the product.

Answer:

Since you ve gotten this product at no cost ( by the way you describe it), and I looked at the web site, I d say yes it is ok to use. I ve always used a specific waterproofing called Red Guard.And I know water proofing isn t cheap. Since this is a brush or spray on type of coating, it will be thin enough to get a nice smooth layer for tile. I would check and make sure its ok for vertical walls application. But I strongly suggest using the strongest latex modified thin set there is. This is what I need to bond to the Red Guard I use. Another suggest and I have to do this too, is to tape all areas with thin set and cement board tape and let dry. Getting all areas. Good time to think about a recessed shelf for shampoos and soaps. Any questions you can e mail me through my avatar and check my qualifications there. GL
May 11, 2017
bad idea. you are writing about a roofing material and your cement board already is the right material to use. topcoat means just that. is the GAF product to be the finish of your bath? course not!
May 11, 2017

Share to: