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Install Hardiebacker in Bob the Builder’s Way

Suppose, you have Hardiebacker cement boards. Unfortunately, you don’t know the exact process of using them. 

For this, you can’t even put tiles on the floor of the bathroom!

Things like this can easily make you disheartened.

How to install Hardiebacker?

The whole installation process can be divided into three segments, gather, inspect and set. Firstly gather the necessary equipment needed to install the board. Check the floor of your bathroom then. See if it is okay to set the boards or not. In the last and final step, set the boards on your floor.

To complete the ways of installing the Hardiebacker board, you need more precise information.

And just for you, I bring in this article. Once you go through it, you will get all the knowledge necessary.

Off we go then!

How to Add Hardiebacker Cement Boards on Floor

Hardiebacker is a must. Whether remodeling your bathroom or making a new bathroom. It consists of three major steps: gather, inspect and install. 

Following these step-by-steps will make it easier for you to install the boards.

That’s why let’s see what these steps are.

First Thing First: Gather Equipment

Before starting any process you will need the required instruments. That’s exactly what we are going to do. 

In the installation of the Hardiebacker board, you will need some general plumbing instruments. Here is the list:

  • Hardiebacker boards
  • Mortar cement
  • Alkaline-proof glass tape
  • Trowel
  • Backer board bolts
  • Knife or board cutter
  • Drilling machine

These are the required tools you will be needing to attach the cement board. If you have them, then you can directly proceed to the next step. 

If you don’t have them, don’t worry. You can easily find them at your nearby plumbing store!

Second Step: Inspect the Floor

This is an important step for adding the Hardiebacker board. You cannot just put the board on the floor. 

You have to check the floor first. If the floor is okay, then you can put the board on. Otherwise, you cannot.

While inspecting the floor, two major things you have to diagnose. The depth of the floor. And if the floor has any damage or not. 

Let’s see what they actually are, shall we?

First Inspection: The Depth of the Floor

You have to check the depth of the floor. The Hardiebacker board can only be placed on a floor that has a certain thickness.

The minimum thickness of the floor should be ⅝ inch. If the floor of the bathroom is made of wood. Otherwise, the floor cannot hold the board. 

That is why check the floor thickness. Measure it. If it has a thickness of more than ⅝ inch, you can put the Hardiebacker board. 

Careful! The thickness should not exceed 16mm as well. If the thickness is 16mm, then you have to check the building code. Whether you can use the board or not.

Second Inspection: Does the Floor Has Any Damage

You have to check the floor if it has any damage or not. The Hardiebacker board can be attached to only clean and smooth floors.

If the floor has any damage or missing parts, make sure they are repaired.

Once the floor is clear of damages, it will become structurally smooth. 

Only then can you set the boards.

There you go. This is where the inspection segment stops. If the floor of your bathroom seems ok, you are good to go. The next step: Installing the Hardiebacker board.

Final and Foremost Step: Setting the Backer Board

Here comes the final step. In fact, it is the major step. It is time to attach the boards to the floor. Without further ado, let’s check these steps and the process!

Cut the Board

To start off, you have to cut the board first. Measure the area of your floor. This way you figure out the required amount of board pieces you will be needing. 

Mark the board in the pattern of the required pieces. You can use a pencil and scale to sketch the marks.  

Once it is done, take the board cutter or knife. Cut the board. This way, you will get the board pieces.

Put the Mortar

The next step is to put the mortar over the floor. For this, get the mortar and trowel. 

Use the trowel then to spread the mortar all across the floor. Using the trowel will help you evenly spread the mortar over the floor. 

Add the Boards

After setting up the cement layer, it is time to put the backer boards. Get the pieces of the backer boards. Gently slide them over the floor. 

The boards will get attached to the soaked cement and will get easily added to the floor. After this, you have to wait till the mortar cement dries.

The next thing you have to do is drill some bolts in the boards. For this, you can use the plumbing bolts. 

Mark the places over the boards. Grab a drill machine and drill in the bolts. The bolts can strongly keep the cement boards under your tub.

Give a Finishing

All right. The addition of the board has been done. It’s time to give a final finish to the board.

To do so, again grab some mortar cement. Put a layer of cement over the joining lines of the board pieces. 

This layer of cement works as extra support to hold the boards on the floor. Make sure you have filled up all the joints with the cement!

After that, cover up the mortar layer with fiberglass tape. And with this, the attachment process of the Hardiebacker board ends! 

Speaking of fiberglass tape, how would you measure the amount of tape?

Here, you can check out these fiberglass tape measures-

Product 1
Product 2

They are the best right now in the market. Give them a try and see for yourself!

Few Precautions to Keep An Eye Out

Hoorah! Up to this far, you have learned the process of installing the Hardiebacker board. 

Unfortunately, it is not the end of the knowledge quest. 

Rather there are a few more things that you must keep an eye out for. Otherwise, the whole installation might go messy. 

Just like removing a permanent marker from the rubber.

No need to feel bored. These are just some general important factors regarding the installation of the Hardiebacker board. 

Here they come!

Mind the Gap

While putting the boards, make sure you maintain the between the boards and the floors. The floor and the edges of the board should not get in contact with each other.

You can maintain a gap of at least ⅛ inch from the floor, to the least. 

Also, you have to keep some space between the boards as well. For this, you can maintain a gap of somewhat ⅛ inches.

Carefully Align the Boards

Make sure the boards you have installed are properly aligned. In this case, try to maintain a slab-type pattern.

It becomes easy to set tiles on the boards afterward.

Another important thing. Never put the boards in such an order that they align with the floor joints.

Especially, make sure that the four corners of the floor do not meet together. Otherwise, when you try to put the tile over the board, you may face difficulties.

If the joining line of the boards aligns with the floor, gaps will get created. There’s a chance that the water may go under the floor

There you go. Keep these things in mind. And no one can stop you from perfectly installing Hardiebacker!


Which face of the Hardiebacker should stay out?

Whether a coarse or smooth plane, You can put any side out of the Hardiebacker. It depends on the tile placing. If you use cement to attach tile, keep the rugged face of the board. On the other hand, you have to keep the sleek plane of the board out. If the adhesive you are using is tile mastic.

Is it necessary to use a thin-set with Hardiebacker?

Yes, you should use the thin-set while mounting the Hardiebacker. In fact, Hardiebacker highly recommends using a thin-set, especially using the Master blend. Thin-set helps to keep the backer board fixed in its place. It fills the space between the floor and the board at the same time.

For the shower wall, do I have to use a vapor barrier with Hardiebacker?

Yes. According to general local building codes, using a vapor barrier is mandatory. During the shower, a lot of vapor gets created. This vapor can harm the drywall or other infrastructures. Guess who prevents this? The shower barrier! The barrier can also stop the water from damaging the walls.

Last Words 

Fellow reader! Our quest for knowing how to install Hardiebacker has ended. 

If you have come this far, surely you have mastered the way of installing this cement board.

If you think you are not ready, don’t worry. There are many plumbing experts out there. You can seek them for guidance.

Our path divides here.

Happy board mounting!