[Explored] Do I Need to Seal Cement Board Before Tiling?

Cement boards are known as water resistant and widely used as a backing for tiling. Cement boards are a great choice as they can provide shields to tiles against moisture which increases the strength and durability of tiles.

Now you may wonder whether you can place tiles directly on the cement board without sealing or not. Well, the answer varies from person to person, but generally, you need to seal the cement board before tiling but it’s not a necessary thing to do. There are several reasons behind this and here we are to help you to learn about this.

In today’s article, we have discussed why you should need to seal cement boards. We also have provided the advantages and disadvantages of doing so. So, without any further ado, let’s begin.

Is It Necessary to Seal Cement Board Before Tiling?

Sealing cement board before tiling isn’t necessary but doing so can be beneficial for you. Now you may ask why as the cement boards are known as water resistant. First of all, sealing a cement board means making it waterproof. Water resistance means that an item can resist water till a certain limit but not resist fully. Whereas waterproofing means resisting water completely.

Generally, cement boards are porous and due to this, they may absorb water. If you are living in a rain or flood-prone area, then the water-resistant ability may fail and, in that case, you will need to seal your cement board. Sealing cement boards ensure higher longevity of tile installations.

Moreover, if the cement boards aren’t installed properly or you are using old cement boards, then sealing cement boards before tiling is a must!

However, sealing cement boards will charge you some extra bucks but it can assure you more durable and water-resistant tile installation.

Pros and Cons of Sealing Cement Board Before Tiling

There are both advantages and disadvantages to sealing cement boards. Here the pros and cons of sealing cement board are provided –

Pros of Sealing Cement Board Before Tiling

Here are the pros –

• Increase water resistance and make the cement board fully waterproof.
• Ensure higher longevity of tiles.
• Prevent mold growth underneath tiles.
• Protect the subfloor or walls.

Cons of Sealing Cement Board Before Tiling

The cons are –

• Need to spend extra bucks.
• Will need to hire labor for sealing cement boards. 
• Chances of potential damage to the finished surfaces.
• Frequent maintenance is needed.

Bonus Tips

For your cement board, you will need to choose the sealant wisely. For heavy rain-prone areas or high moisture environments, then you must need to use Silicone Caulk or Epoxy Grout. For a low moisture environment, you will need latex-based sealant.

Frequently Asked Questions and Answers 

Can I place the tile directly over the cement board?

Yes, you can directly place the tile directly over the cement board. For this, the cement board needs to be primed and installed correctly.

Do I need to prime the cement board before tiling?

Actually, it depends. If you are using an adhesive like BAL White or BAL All-Star then you won’t need to prime the cement board. However, priming isn’t necessary in every instance, but doing so can be beneficial for you.

What do I put over the cement board before tiling?

There are a few things that you can put over the cement board before tiling. For example, you can put a waterproof membrane over the cement board for increasing water resistance. And then you will need to put thin-set mortar all over the cement board.

Conclusion

To sum up, it’s not mandatory to seal cement boards before tiling. However, sealing the cement boards ensure tile longevity, making the board waterproof, and so on. If you are living in a low-moist area then you won’t require sealing the cement board but if you are from a high-moist area then sealing the cement board will be a wise decision!