What Size Bolt Do I Need for a Floor Flange?

Floor flanges are an essential structural element of your fencing system. The flange is foundational and allows you to install, level, and secure fence posts quickly. Floor flanges are designed with pre-drilled holes for easy installation on concrete or wood surfaces. The most important aspect of a floor flange is the post size it accepts, though you may consider the diameter of the pre-drilled foundational holes and the distance between them. If you are replacing old floor flanges or have leftover anchor bolts from another project, you may consider purchasing a floor flange that meets post-size criteria AND eliminates the need to drill new surface holes. You may also just be wondering what size bolts you need to purchase. In any case, let's discover what size bolt you will need for your floor flange.

What Is the Diameter of the Bolt Holes On A Floor Flange?

When purchasing a floor flange, you must also purchase anchor bolts to secure the flange to a solid surface. The diameter of the floor flanges' holes will indicate which size bolts to use. At Chain Link Fittings, we work hard to provide you with all the information and dimensions you may need for purchasing fittings and materials.

Often, the diameter of the surface holes on a floor flange is 3/4" or 3/8". This measurement can be found in the product description as "Anchor Bolt Hole Size." If the diameter of the hole is not explicitly stated, there are likely two other ways to find the information you need about a product. Every product page will have an image of the product on a grid, allowing you to visualize the size of the product inch by inch. You may use this grid image to estimate the size of the hole. Some product pages also offer an image with specific measurements of every aspect of the product.

Floor Flange Example Measurement Diagram

This is an example of a product image with measurements.

These measurements do not apply to all floor flanges.

Floor Flange Example Grid Image

This is an example of a product image on a grid.

These measurements do not apply to all floor flanges.

What Size Anchor Bolt Do I Need For My Floor Flanges?

The diameter of the holes will directly indicate the diameter of the anchor bolt. A hole 3/4" in diameter will require a bolt that is 3/4" in diameter. A hole 3/4" in diameter will need a 3/4" in diameter bolt. The length of the anchor bolt is dependent on the surface application.

Need More Information About Bolts For Floor Flanges?

If you have thoroughly read the product description, viewed all the product images for measurements, and are still unsure of what size bolt you need for your floor flange, please contact our sales representatives. They are happy to assist in any way they can.

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