We just removed the old floor from our bathroom. My husband is going to put down 3/4" plywood and then 1/4" Hardibacker on top of that. Is it okay to use pre-mixed thinset mortar to set the Hardibacker on top of the plywood?
Also, do you use a square-notched 1/4" trowel to apply the thinset?
Thanks a bunch!
PS... I don't know if it matters, but we're going to put tile on top of the Hardibacker.
the premixed thinset mortar should work fine, but also use hardibacker screws as well. i'd say one screw about every 8-12 inches in both directions. you do want to use the square-notched 1/4" trowel as well, just be sure to put the thinset on evenly.
STOP!!! DO NOT USE THE PREMIX STUFF. It is junk to begin with, it takes forever to dry and it will compress. Use a thinset that comes in a bag, you mix it with water. This will cover your warranty with Hardie, premix will not. You can use the cheap unmodified thinset or a modified thinset. The primary reason for the thinset being under the Hardiebacker is not to bond so much as it is to fill in any hollow spots that may compress under weight. That is one of the main culprits that will cause your tiles to come loose or crack. You can use backerboard screws or 1& 1/4" galvanized roofing nails to anchor the board to the plywood. Also tape the seams with mesh tape and flash coat with the modified thinset you will use to set your tiles. The plywood seams should be gapped at 1/8" and should be filled with a cheap latex caulk before putting down the Hardiebacker. This will allow the plywood to expand without buckling as long as it is not tight to the walls, should be a 1/4" gap there left open or caulked, but no thinset in that gap either.
- 15 Old House Features We Were Wrong to Abandon
- 17 Tiny Bathrooms We Love
- 20 Insanely Easy 60-Minute Home Improvements
- 70 Gardening Tricks and Ideas for Total Beginners
- 16 Inventive Beds You Can Make Yourself
- Top 10 Classic DIY Projects for the Outdoors
- 15 Once-Popular Household Items That Are Vanishing
- 159 Smart Storage Ideas for the Whole House
- 30 Things Every Adult Should Know How to Do
- 10 Wise Ways to Get Rid of Pests and Critters
- Before and After: 9 Totally Amazing Mobile Home Makeovers
- Top Tips for Keeping Countertops Like New
- 15 Amazing Things You Can Make with $0 Scrap Wood
- 14 Ways to Get More Kitchen Counter Space
- Assembly Required: 15 DIY Kit Homes
- 18 Bathroom Updates You Can Do in 1 Day
- 9 Tried-and-True Methods of Eliminating Weeds
- Picture-Perfect Patios: 10 Outdoor Spaces to Love
- 11 Clever Alternatives to Kitchen Cabinets
- 7 Easy Budget-Friendly Backyard Makeovers