Painting Water Resistant Wallboard
I have just done a renovation on my bathroom walls and installed a waterproof cement board on the walls and ceiling. I'm tiling the walls, but I don't want tiles falling on our heads. Can I paint with regular latex paint over the cement board?
Painting cement board is not really a standard practice, but it can be done. Seal the seams with standard wallboard tape and compound. Since the product does not have the tapered edges of wallboard, you must feather the compound out at least a foot on either side of the joints to give the illusion of a flat surface. Use a water-based primer/sealer for the first paint coat, followed by a coat or two of a mildew resistant bathroom paint. A washable eggshell or semi-gloss latex paint with a mildewcide added would be my distant second paint choice.
If you find the finish on the cement board to not be to your liking, you can always use a texture paint to mask any defects. Of course, at least one coat of a mildew resistant paint should be applied over the texture paint. Texture paint is too thick to mix a mildewcide into, and it will definitely mildew over time!
Water resistant wallboard would have been a better choice for a painted surface. It is designed to be more easily cut and finished like regular wallboard, but withstands much higher moisture levels without damage. There has been some controversy about this product, and most tile contractors no longer use it within shower and tub enclosures as a backer, preferring the various tile backer board products.
As an aside, being a curious-cat, I decided to do a simple product test of water-resistant wallboard a few years ago. I took a 6" x 6" piece, placed it into a large pan of boiling water and let it boil for an hour. The result... there was no deterioration in the paper whatsoever (though it did absorb water), and the solid core showed not the slightest bit of softening.
So the question that arose in my mind was... why is this product frowned upon? Though not a complete answer, I realized the sad truth was that contractor error or irresponsibility could be part of the problem, not the wallboard. I have done at least 50 tile repairs in fairly new homes... less than 12 years old... caused by water leaking behind tiles in enclosures. What I have found consistently is that the contractors used regular wallboard, not water-resistant wallboard, in these failed jobs! I have personally never seen water-resistant wallboard properly installed on walls or ceilings fail due to dampness in residential conditions.
COPYRIGHT 1999 G.G. ALONZY
Have a small home repair question for THE NATURAL HANDYMAN? Just click here www.naturalhandyman.com/aitikia
For more home repair information, visit NH's growing list of original home repair articles and quality links www.naturalhandyman.com
If this information has been valuable to you, please consider making a small donation to support NH's free service to the home repair community! For more information, please visit our "Friends" page www.naturalhandyman.com/friends
The Natural Handyman Site Directory
- Home Repair Articles www.naturalhandyman.com/iip
- Home Repair Links Library www.naturalhandyman.com/linkslibrary
- NH's Bookshop www.naturalhandyman.com/bookshop
- Find a handyman at www.naturalhandyman.com/network
- Win unique home repair gifts and prizes at www.naturalhandyman.com/contest
Please read the important copyright and disclaimer information is located at www.naturalhandyman.com/copyright
More Tips & Tools to Help You
Live Better...For Less
- 6 cheap, effective home security solutions
- 5 frugal ways to expand your living space
- Top 10 DIY mistakes made by home 'handymen'
- 15 mistakes to avoid when selling your home
- 9 ways to buy furniture for less
- Need a bigger home? How to maximize the space you already have
- Find the best mortgage rates in your area
- 3 ways to use a mortgage calculator
- Mortgage calculator: Calculate your payment and more
- Home equity calculator: HELOC vs. line of credit
- Should I borrow from my home equity?
- How much can additional payments save me on my mortgage?
- Who offers the most home insurance discounts?