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 Shouldn't Abandon
- 17 Tiny Bathrooms We Love
- 20 Insanely Easy 60-Minute Home Improvements
- 70 Gardening Tricks and Ideas for Beginners
- 16 Inventive Beds You Can Make Yourself
- Capitalize on Your Attic: 10 Inspirations
- 15 Once-Popular Items Now Vanishing
- 159 Smart Storage Ideas for the Whole House
- 30 Things Every Adult Should Know How to Do
- 16 New Ways to Store Kitchen Necessities
- 12 Garden Sheds You Could Live (or Work) In
- Design a Rustic Bathroom: 10 Inspirations
- 7 Easy Budget-Friendly Backyard Makeovers
- 283 Great DIY Project Ideas
- 9 Budget Ways to Revive Your Porch
- 10 Clever Uses for Space Under Stairs
- 17 Backsplashes for a Unique Kitchen
- Assembly Required: 15 DIY Kit Homes
- Make Your Small Bathroom Feel BIG
- 108 Easy Outdoor Living Ideas
- The Right Path: 15 Wonderful Walkway Designs
- 10 Smart New Uses for Old Tires
- 14 Room Dividers to Organize Your Space
- 15 Eye-Catching Options for Your Front Door
- 15 Unexpected DIY Flooring Alternatives
- Design a Better Bedroom: 9 Strategies
- 21 Paint Colors That Never Fail
- 1 Dozen Ways to Maximize a Small Yard
- 9 Easy-to-Make Garden Luminaries
- Would You Live in a Floating Home?