It’s cost-effective to build your fence. It’s not too complex and does an excellent DIY project. Any fence’s support posts, which are typically concrete-anchored, are what give it its strength and support. The fence posts can be installed with just about any concrete mixture. Specific concrete mixes do, however, work more effectively than others. There are also a few substitutes, such as the expanding foam Sika Fence Pro Mix.
Concrete is the most durable material for placing fence posts, mainly if your soil is sandy. Gravel may work sufficiently in clay-rich and thick soil, but concrete is the only material to maintain your fence posts in place in looser soil.
Choices for concrete
You have three basic choices for concrete:
- Buy a bag that has already been mixed.
- Mix it yourself.
- Purchase it from a supplier.
I advise choosing premixes for modest to medium-sized projects. Typically an 80-pound concrete bag or a 50 lb sack work for simple tasks. However, if you use smaller bags, numerous bags will still be required for each hole. Of course, the depth and size of the hole will determine this, but I often estimate using two bags per hole.
How long do posts need to cure in concrete?
Generally, you may start putting weight on the posts after 4 hours, but it’s best to wait at least 24 hours before endeavoring to construct a fence. Before applying any pressures to the posts, standard concrete mixtures should cure for 24 to 48 hours and take up to two hours to set.
Cost
Fast-setting concrete is somewhat more expensive per bag than standard concrete. However, pricing differs by retailer and area. In light of this, the difference might not appear significant if your project is tiny. However, regular concrete can be preferable if the job is enormous.
Sika Fence Post Mix
Fastest Setting Fence Mix

The Sika Postfix Fence Post Mix is the absolute best concrete mixture for setting fence posts. This is a better option than concrete for fence posts, even though it’s more like an expanding foam than a concrete mix. It’s ideal because it’s quick to set up, incredibly handy, and simple to operate.
It’s an Amazing Product! Sika Fence Post Mix is designed exclusively to install a fence post. It’s not, however, made of concrete. A pre-measured, two-part polyurethane resin is used. It takes less time to set fence and gate posts with the same strength as cement. Sika’s expanding foam contains two components mixed in the bag and used to support non-structural posts like fences, mailboxes, and signposts. This pre-portioned, two-part polyurethane expanding foam has been designed to be lightweight and quick-setting. This high-strength backfill is appropriate for many projects for in-ground supports made of steel, PVC, or wood.
PROS
- Takes 3 minutes or less to set
- Replaces two 50 lbs. of concrete mix
- High strength and water absorption resistance
- Easy to use: just roll, mix, and pour
- No water required
- Secures and guards the post’s base
- In every weather condition, strong and resilient
CONS
- Unable to form
- Seal on bags can be difficult to break
- Can be more expensive than traditional concrete
- If sand or loose soil conditions are present, there may not be enough compression on the foam to retain the essential form to offer support
- Activates quickley
Quikrete Fast Setting Concrete Mix Fast Setting Bag 50 Lbs
Best Traditional Concrete Mix

Quikrete Fast Setting Concrete Mix is another great choice for fence posts. Conveniently, Quikrete fast-setting concrete does not require mixing. If you desire simplicity when it comes to traditional concrete mixes, Quikrete Fast Setting Concrete Mix is the way to go!
It is a ready-to-use concrete mixture that hardens up quickly and doesn’t require mixing. It’s as simple as pouring the mixture into the hole and then adding water. It has a 4000 psi pressure, is simple to work with, the result will be sturdy enough for fence posts, and you’ll avoid the hassle.
The fast-setting mix from Quikrete is, in my opinion, a great concrete mix for fence posts. This product, used frequently to put fence posts in concrete, is a nice choice if you want to promptly and simply place fence posts before continuing with the remainder of the fence installation. Setting posts for items like mailboxes, fences, and lighting is effective. Moreover, a post installed with quick-setting concrete may support enormous weights like fences and other heavy loads in just four hours.
PROS
- Sets without mixing
- Strong and resilient in every weather
- For a much better look, it is possible to shape and smooth
- It sets in about 10-15 minutes and is sculptable or moldable into place
CONS
- Concrete may become weak if the mixture is overwatered
- Heavy, requires water
- Can be messy
- Takes longer to fully cure
- Needs to cure in optimum weather temperatures
Fast 2K Fence Post Mix
Best Concrete Alternative Mix

Fast 2K Fence Post Mix is a unique expanding composite made to fill the space around a post’s hole so that it can support the weight. Fast 2K deck post anchor expands on 20+ years of experience creating composite backfill materials for installing utility poles and fences. These products are used every day.
Fast 2K deck post anchor adheres to wood, vinyl, and metal posts for decks, fences, and even mailboxes. It uses a proprietary expanding composite technology stronger than standard concrete or other post foam mixtures. You can secure your deck or fence in 15 minutes, thanks to the rapid, lightweight technology that substitutes 80–100 pounds of concrete with a 2.5-pound bag that doesn’t require water for mixing.
Fast 2K Deck is waterproof and hydrophobic, which prevents water from getting into your posts and causing rot, rust, degradation, and other water-related damage. In contrast to concrete, which absorbs water and can harm metal and wood, this avoids corrosion.
Brand-specific Fast 2K Fence Post Mix closely rivals the SIKA Postfix Fence Post Mix. A 4-pound Fast 2K Fence Post Mix bag replaces 80-100 pounds of conventional concrete. Compatible with various materials, including steel, wooden, or vinyl posts, it requires no water and does not absorb water. It is created using a novel expanding foam technology.
Although it costs a little less, this mixture is comparable to SIKA Postfix Fence Post Mix. Although it isn’t as well known as the SIKA model, it has many satisfied clients.
PROS
- Lightweight
- Sets in just 15 minutes
- Minimal cleanup work after setting
- Install poles and posts without bracing or mixing
- Keeps water from seeping through each post’s seams
- Built using the same industrial technology used for more than 20 years by contractors to construct power poles
CONS
- Chemical formula
- Fast sets provide no room for mistakes
- Activates quickly
- Costly
Sakrete Fast Setting Concrete Mix
Best Beginner Friendly Concrete Mix

Sakrete high-strength concrete mix is a blend of Portland cement, cleaned and graded sand, and gravel for use in construction and repair projects where the concrete thickness is greater than 2 inches. This concrete mix is perfect for footings, securing poles and posts, and pouring curbs, steps, and driveways.
This mix does away with the traditional mixing in a wheelbarrow and overnight setting period of ordinary strength regular setting concrete. According to the directions, you should mix it with water immediately in the hole, and the fast setup time is ideal for most projects. Sakrete is simple to work with and hardens in the perfect length of time. Since it forgives incorrect water measurements, when the mixture becomes excessively moist, it nevertheless sets in the appropriate length of time.
Dig your hole, place your post, add 1/3 water, then throw the concrete into it. Ensure that your post is level before the concrete hardens.
PROS
- Durable
- Sets in just 30 minutes
- Install poles and posts without bracing or mixing
- Commercial structural applications ensuring quality and strength of 4000 psi and outstanding durability
- Excellent for pathways and slabs that need immediate access after installation
CONS
- More expensive than standard concrete
- Provide minimal building needs
- Longer cure time
- Needs to cure in optimum weather temperatures
In The End
As stated above, In my opinion, The Sika Postfix Fence Post Mix is the best. It’s an easy and effective product. This foam mixture has demonstrated time and time again that it works just as well for setting posts of any kind and is much simpler to work with.