Precast vs. Site-Cast Fence Installation Process

Engineers looking at structural plan

A precast concrete fence will look very similar to a site-cast fence, but the process to get there can often look very different. It is the process to make a precast concrete fence that equals a stronger, better performing fence.

Here is an overview of how to create a concrete fence using both methods:

Planning

With precast concrete installation, you will first need to focus on getting measurements and a plan. The main measurements will be the area where the fence will be installed. The required base and wall thickness for concrete fences will be different for each city, so check with the right officials to get that information. Once you have the measurements and the plan, you can submit these to the precast concrete manufacturer.

This step is very similar when using site-cast concrete – take measurements and develop a plan.

Permits

While you are talking to your city officials, you will need to check into getting a permit. You will need to show them how the fence will be built, and those plans need to reflect the building requirements for each municipality.

With precast concrete, you will often just need a building permit. If the type of precast concrete fence you are using requires you to use a crane to unload the pieces from the truck and set them in place, you will need a crane permit too.

Again, this step will be very similar when installing a site-cast concrete fence.

Preparation

After approval of permits, your precast concrete manufacturer will start up production. This will involve putting together the correct forms, installing reinforcement, and starting to pour each panel. Since the manufacturer takes on all this work, it’s a task you don’t have to think much about.

With precast concrete, you will next need to prepare the gravel base, which typically should be 8-12 inches of compacted gravel. During the planning and permit stages, you should confirm the required base depth with officials, as each city will have different requirements. You will also need to drill the piles that will be the support for each post in the panel and post fence setup.

Most cast in place retaining walls will require a concrete slab that the form will rest on. After construction of the slab, the form will be built, and rebar installed. This is very similar to what the precast concrete manufacturer does in their facility, but the difference is it’s being built on-site – making it your concern too. You will need to schedule a date for the concrete pour and coordinate the concrete trucks, possibly a concrete pump truck for hard to reach areas, and the workers, too.

Assembly

At this point, your precast concrete fences have been completed. Each part has been tested for quality and then shipped to the site location. Start with erecting the first wall by sliding the post onto the pile. Install the second panel by sliding the wall panel into the groove in the post of the first wall section. Install the caps on the top of each open post. Complete the installation of all the parts of the fence before sealing against moisture.

At this part of the process, things look very different when installing a site-cast fence. Timing is very important. At the scheduled time, your concrete trucks will arrive, and testing will proceed. If the concrete passes the tests, the pour will start. The concrete will need to be vibrated into the form to remove voids. Once the pour is finished, you will need to allow the concrete to cure for a specific amount of time, at which point the forms can be removed, and the fence can be sealed against moisture.

Backfilling

With both precast concrete and site-cast concrete fences, the area around the wall will need backfilling. Backfill helps to support the wall and to drain water away from the base of the fence. Any backfilling will need to be approved by an engineer. Too much backfilling with not enough internal support could cause the wall to fail.

When it comes time to build and install your concrete fence, be sure to choose precast and contact American Precast Concrete to request your personal quote.