Installing hardi backer over concrete.

[@douglefever7807]

U R my hero! I've wanted to do this for a long time now in my home, but I'm a DIY dude not a contractor. I could not find anybody who could tell me why NOT to do this, but I could not find anybody who successfully did this with good results. THANK YOU!

[@onetruesoldiervt3686]

That's the best way to go though vertical or flat I apply hardy board for everything but I always mud whatever I'm attaching the board too then I nail it guaranteed to never pop

[@stevenschuster]

This was a good video, thanks. I was wondering how that foolr is holding up? If you know. Im building a transitionless shower on concrete slab. I need to raise the floor up to match the 1-1/8" Ditra shower pan that will also be on slab. The plan is to use multiple layers of concrete backer/hardi board to accomplish this. A Ditra heat duo membrane will be the final layer. so 1/2" + 1/4" + 5/16" = 1-1/8" I was considering using the Hardi board (1/4") first on the slab then a 1/2" exterior grade plywood then regular Ditra Heat (1/4"). how would I bond the plywood to the Hardi board ? I could go Hardi board, 1/2" cement board, then Dirta Heat Duo (duo has the thermal break) ? Thoughts? Anyone? Lol.

[@onetruesoldiervt3686]

Did you mud underneath the backy boards that would be the way to go if you don't want any popping up

[@thekevinnorton]

This is exactly what I'm thinking of doing in a room that has carpet currently and needs 1/2 to come level with tile throughout house so I can lay Vinyl plank. Question if I only use thinset do you think I would have issues over concrete.

[@arrowheadtileandstone8973]

I personally don’t think you would have an issue as long as you use good quality modified thin set and the slab is scraped clean of all paint/etc. I would at least put a few ram set nails in each sheet, in the corners and a couple out in the field just to be safe.

[@thekevinnorton]

@@arrowheadtileandstone8973 thanks for your reply - yeah I think I will go with a few ramset nails.

[@thekevinnorton]

@@arrowheadtileandstone8973 also as far as products , would fiberock also work .

[@arrowheadtileandstone8973]

@@thekevinnorton I prefer hardibacker

[@Ashhh9009]

So what type of drill or nail gunur using to put the hardiebacker over concrete

[@ThaiNguyen-ut4cp]

Thanks for this video. New diy. Can I use 1-1/4 inch driver cement screw to screw a 1/2 inch board to the concrete slab? Do I need to put thinset before laying down or I can bypass it since I’m screwing it down? If not thinset, can I use liquid nail to do it? I’m hesitate to use thinset since I don’t have any or afraid to use thin-set

[@arrowheadtileandstone8973]

That will work more than likely, it will take a lot longer though. It’s best to use thinset so it stops the hardibacker from flexing on the low areas.

[@arrowheadtileandstone8973]

Is there a reason you’re trying to put Hardibacker over concrete?

[@ThaiNguyen-ut4cp]

@@arrowheadtileandstone8973 my living room has carpet and kitchen has tile. I’m putting laminate through my house but after doing some minor demo on the ceramic tile. It’s just too much work and so much dust. After looking at your video. I could use 1/2 board to even the floor with the ceramic tile in the kitchen and I can just lay laminate over the tile. Wil that work?

[@arrowheadtileandstone8973]

Awesome ya that’s a good option.

[@arrowheadtileandstone8973]

Just use a modified thin set and ram set or concrete screws to keep it down until it dries. You don’t have to hit every 6 inches just the corners and a few in the middle until it dries. It’s a little different for tile but if you’re using LVP or laminate just tack it down and let it dry

[@mamehuewitt10]

So, to be sure. If I use concrete screws, I won’t have to use thinset underneath the boards? And if I use nails, use thinset underneath? I know I will tape and thinset the tops, but just want to verify the underneath for Hardiboard on top of concrete slab.

[@arrowheadtileandstone8973]

I would feel confident with that method. I prefer to thinset the hardi down either way though

[@stevehamman4465]

Thinset is a cheap and easy way to be sure!

[@eastcoastgaming8652]

Thanks for the video! If installing over concrete, what type of screws are to be used?

[@arrowheadtileandstone8973]

You want to use a powder actuated “ram set” with 3/4”-1” concrete nails. Make sure to use modified thinset to glue it down.

[@eastcoastgaming8652]

@@arrowheadtileandstone8973 Thank you!

[@jen318]

What if the nails don't go all the way down from ramset

[@arrowheadtileandstone8973]

A small sledgehammer works pretty well to pound them down. The Ramset should have a setting on it to go deeper and different types of shells depending on how far you need to go down.

[@twoserve2449]

Why would you install hardy backer over a surface that is already for installing tile over??, all you needed was a good coat of MBP

[@arrowheadtileandstone8973]

This house had sections of concrete and raised foundation. Hardi wasn’t necessary I just happen to have a bunch on hand.

[@arrowheadtileandstone8973]

It basically went from raised foundation in the kitchen, to concrete slab in the dining room, back to raised foundation in the laundry.

[@twoserve2449]

@@arrowheadtileandstone8973 ,oh I see, that makes senses! 👍