Expanding Foam vs. Concrete for Fence Posts: Making the Right Choice (2024)

FAQs

Expanding Foam vs. Concrete for Fence Posts: Making the Right Choice? ›

Expanding foam and concrete are promising options for post-hole fillers. Concrete is more durable and can support load-bearing posts. Expanding foam works best for lightweight vinyl or mesh fences. Concrete takes longer to set and cure.

Some believe that concrete can provide a more solid foundation that lasts longer than expanding foam. However, that has never been proven. However, expanding foam is much easier to use, and since it can expand, you can virtually secure it to any type of elements found in the ground for the hole of the post.

Whether you're building a fence, setting a mailbox or even a basketball goal, the best way to ensure your posts will stay sturdy and true for years is to set them in concrete.

Less Control and Over-Lifting

Foam's chemical reactions are also highly sensitive to temperature and pressure, and the pressure of the confined space under the slab can lead to inconsistent expansion. These factors reduce control and make it easier to overdo the repair and lift the slab too far out of place.

Chips and cracks: While they're in good condition, concrete posts are virtually indestructible, but they can sometimes chip or crack, allowing water to seep deep into the post. Over time, this can cause the crack to worsen, exposing the reinforcing metal wires to rust and eventual fence failure.

While expanding foam can secure posts for lightweight fences, such as vinyl or wire mesh, it's better to go with concrete for structural posts, such as posts for porches, decks, or large and heavy gates. Expanding foam is not as strong as concrete when supporting load-bearing posts.

Concrete is more durable and can support load-bearing posts. Expanding foam works best for lightweight vinyl or mesh fences. Concrete takes longer to set and cure. Expanding foam is more expensive than concrete.

Materials Used to Strengthen or Install Fence Posts Without Concrete. There are a few options for materials to set your fence posts if you aren't using cement. These include dirt, gravel, sand, and crushed rock. Dirt: Filling the hole with dirt and compacting it will help to support the fence post.

The best recommendation for setting fence posts of any kind is to always secure all metal fenceline poles in cement, plus all wooden corner and gate posts as a minimum. Doing so creates a footer that prevents the post from rising out of the ground or leaning for any reason.

While foam concrete leveling is typically the most expensive of the three methods out there, it can still save you quite a bit off the cost of total concrete replacement.

Can you use foam instead of concrete? ›

Fast 2K™ fence post foam is an alternative to concrete for setting posts, poles, signs and much more. It is a two-part proprietary polymer that expands to fill the peripheral void between the post and the hole, using the same technology applied by H.B. Fuller to set utility poles for over 20 years.

Disadvantages: Foaming and stabilizing surfactants used in conventional foamed fluids do not fully degrade in the environment. Advantages: Foams can dilute water-soluble fuels and improve the performance of water on solid fuel fires. Disadvantages: Persistent small flames can burn away the foam blanket.

A concrete fence post is an incredibly sturdy material used to create the support posts for your fencing structure. It is often a more desirable option than wooden posts due to its strength and durability. They are extremely difficult to damage, even when exposed to drastic weather conditions.

The strength and durability of concrete fence posts are some of their main draws for most buyers, especially when considered alongside their exceptionally long lifespan. Concrete fence posts can last for up to 25 years, and all with a minimal level of maintenance.

Materials Used to Strengthen or Install Fence Posts Without Concrete. There are a few options for materials to set your fence posts if you aren't using cement. These include dirt, gravel, sand, and crushed rock. Dirt: Filling the hole with dirt and compacting it will help to support the fence post.

Fast-setting concrete is ideal for installing fence posts because it does not require mixing in a bucket or a wheelbarrow, . After you've finished digging your post holes, fill them with three to four inches of gravel and compact it with a post or a 2x4.

Backfilling with Gravel and Soil. Fill the first few inches of the hole with gravel. This aids in drainage, keeping wood posts dry and preventing rot. After the gravel, backfill the hole with the dug-up soil, tamping down every few inches to eliminate air pockets and ensure soil compaction.