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How Many Screws Per Backer Board?

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When you’re planning to install a backer board (or cement board), you might be wondering how many screws to use for your project. Don’t worry! We’ve researched everything and found the answers for you.

You need 55 screws and 91 screws per 3x5 feet and 4x8 feet of cement board, respectively. As for the rule of thumb, you need to screw every eight inches on a cement board except for installing in the ceiling, where you need it every six inches apart.

In this article, we will detail the backer board. We will share with you the benefits of backer boards, step by step process of installation, and some safety tips. So keep on reading!

Architectural concrete Background & Textures - How Many Screws Per Backer Board

What Is A Backer Board?

Cement boards fitted to a wooden studwork frame in a house

Cement board is another name for backer board. It doesn't include any organic material, in contrast to drywall which does contain some wood. The chance that it will rot, degrade, or foster the growth of mold is thereby decreased. 

The backer board is constructed of cement, silica, water, flour made from ground limestone, and strengthening fibers like fiberglass.

Benefits Of Using Backer Board

Look no further if you need a backer material that is cheap, simple to work with, and durable. Backer boards or cement boards are popular with DIYers and contractors because of the following:

Hold Up Moisture

Backer boards retain moisture better than drywall, but not being completely watertight or moisture-resistant. Because they are less prone to mildew, decay, and decomposition, which naturally occur in moist conditions. They are a great option for humid spaces like your bathroom.

Add Stability

Backer boards provide a robust base for tile, leading to fewer cracks and a significantly better load capacity because they are built and dried off-site.

Easy To Install

It is simple to install and work with cement boards. You save time because these are generally created off-site. This convenience allows you to typically complete your project more quickly. They are also simple to use - just score, cut, and place.

Less Shrinkage

Before being exported, the cement boards go through all shrinkage and expansion throughout the manufacturing drying process. As a result, there won't be any unexpected shifting during or after installation because the cement board is sturdy.

Quantity And Size Of Screws For Backer Board

As the circular saw blade cuts into the cement board, dust creates clouds.

More than just a regular screw is needed for cement board installation; you'll need what are called cement board screws. These are sharp screws that have a specific coating to make a safer cement board installation. 

The general rule is that you need to drill a screw every eight inches on a cement board. In applications involving ceilings, screws ought to be spaced every sixinches. This is to prevent breaking and keep clear of edges. 

Professionals often suggested 54 screws for the countertop, 48 screws for the floor, 26 for the wall, and 30 screws for the ceiling installation per 3x4 feet of cement board. 

In terms of cement board sizes, for 3x5 feet and 4x8 feet, you will need about 55 screws and 91 screws per cement board, respectively.

Additionally, it is recommended to use a minimum of 1 ¼-inch (interior) and 1 ¾-inch (exterior) screws for the flooring and walls. While a minimum of ¾-inch long screws for the countertops.

How To Install Backer Board?

Tile project cement backer board ready for the tile setter to apply thinset and set the tile down during a major house renovation.

Backer board installation is simpler than most individuals believe. Backer boards come in a wide variety, with cement backer boards being the most widely used. 

A drywall-like material called cement backer board is usually used in bathrooms as a watertight base for ceramic tile installation. Water that might inadvertently infiltrate beneath the ceramic tiles won't have an impact on the concrete in the backer board. 

The one disadvantage of it is that it can be difficult to cut since it is so heavy. We can now start learning how to install a backer board with the following steps below:

1. Materials

You need to prepare the materials needed, such as: 

Cement Board Sheets: are typically either ¼- or ½-inch thick, though if you require ⅝-inch thickness, you can find it. 

Screws: You can purchase these screws separately in stores or online, or they may be bundled with your cement boards; just make sure they are marked "safe for cement boards" on the packaging.

Click here to see these cement board screws on Amazon.

Drill: To help you secure screws in the cement board, get a dependable cordless drill.

Click here to see this cordless drill combo kit on Amazon.

Thin Set Mortar: Make sure you have enough thin-set mortar for your project because you will use it several times during the installation procedure.

Click here to see this premixed thin-set mortar on Amazon.

Saw: To cut the cement boards, use a saw. Ideally, choose an electric jigsaw with a six-teeth blade that has carbide tips.

Click here to see this jigsaw on Amazon.

Trowel: Be sure to have a clean, notch-tipped trowel on hand. A corner-specific trowel can also be something you want to purchase to make taping easier.

Click here to see this square-notched trowel on Amazon.

Tape: A full-size roll of fiberglass mesh tape, sometimes referred to as "fiberglass self-adhesive," is required.

Click here to see this fiberglass tape on Amazon.

2. Estimate

Estimating the quantity of backer board you will require. To determine the quantity of the backer board, you need to know the area of the working space using a tape measure. To determine the area, multiply the length and width of the room together. 

Click here to see this self-lock power tape on Amazon.

3 x 5-feet sheets of the backer board are the most common size that making each sheet cover 15 square feet. As a result, you must multiply the room's square footage by 15. 

Your required number of sheets will be rounded up to the next whole number.  Perhaps you should get an extra sheet just in case you have a lot of waste.

3. Prepare

Make sure the room is prepared before attempting to install the backer board. Any flooring that is already there needs to be taken out. Also, take off the wall's baseboards. You are prepared to continue when you reach a wood subfloor.

4. Spread Adhesive

Spread some thin-set adhesive on the floor where you will place the first board to start. Use your trowel to apply some of the thin-set to the floor in a uniform layer. 

Avoid dispensing too much thin-set at once. The backer board is then pressed into the adhesive. Thinset should cover the whole underneath of the backer board.

5. Adhere

The backer board needs to be secured to the subfloor after being positioned into the adhesive. Secure it with screws using a drill. The backer board has a number of holes, as you will see. 

Make sure the screw is inserted into each of these. This is required to ensure that the backer board does not move at all when someone stands on the tile. Just be careful not to break through the mesh when you drive screws flush with the board's surface. Try not to angle when driving screws.

6. Cutting

You will need to cut it when you reach a spot where a complete sheet won't fit. Cut the backing board to size using a saw.

7. Tape

You'll need to seal the seams where the boards meet the floor once you've laid all of the backer board down. To hide them, apply fiberglass tape.

A video demonstration of the installation is shown on YouTube below.

Safety Tips

As you can see, setting up cement backer boards is a really simple procedure. Even the smallest restoration jobs should adhere to a few safety precautions. Follow these instructions to ensure a seamless installation of the backer board:

Invest In Safety Gear

Avoid skipping out on purchasing protective equipment for your project to save money. Inhaling dust from thin-set mortar and cutting backer boards poses serious health risks. Additionally, dust particles can sting your eyes. 

To protect your hands from the thin-set, don’t forget to buy gloves. Also, a mask or respirator, and eye protection when you go shopping. You won't need to buy anything new if you decide to invest in high-quality safety equipment because you may use these tools again for subsequent jobs.

Follow Manufacturer Instructions

Before starting, always read the manufacturer's directions thoroughly. This includes any instructions that are packaged with your backer boards as well as the instructions printed on the bag of thin-set mortar. 

Never think there is a "one size fits all" way for installing a backer board because one manufacturer creates items differently from the next. You can reduce the likelihood of encountering pricey or time-consuming obstacles by following these guidelines before beginning your project.

Use Tools Carefully

If you are not experienced, avoid using a cordless drill or jigsaw. Never operate broken tools and always unplug or turn off all power tools when you are through using them. You should also tie back long hair and loose clothing.

Architectural concrete Background & Textures

Final Thoughts

To make an informed choice when buying supplies and tools for a home remodeling or renovation project, it's crucial to be aware of all options available. 

For the number of screws, as mentioned above the approximate screws per backer board, you only have to multiply this value of screws by the number of backer board sheets you will buy. 

You need to consider where you are going to install it because there are a specific number of screws for specific areas. Don’t forget also that the length of the screws is important.

Before you leave, if you like reading this, you might be interested in some posts we have below.

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