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How To Install Conduit In An Existing Concrete Slab

How To Install Conduit In An Existing Concrete Slab

Adding a conduit to an existing concrete slab can be a great idea depending on the project that you want to do. But it does take a lot of time and effort. Many homeowners consider working with a professional plumber. While this method may be easier, it can cost a lot of money. Rather than spending all that money or living with inadequate existing plumbing, you can do the work on your own. 

Installing the Conduit in Your Existing Concrete Slab

Installing a conduit properly through a concrete slab is sometimes difficult. But it is something that you can do on your own from home if you’re willing to put in the time and effort.

Some of the steps that you can take to do this for yourself without the expense of a plumber or other contractor includes:

Measure and Purchase Pipe

The first step to take is to take measurements and then purchase the pipe that you need. You will need drawings of your home or the building to help take some of the measurements. You should look closer at the measurements that are written down and then use a measuring tape to map out the location of the pipe under the concrete slab. This is the most accurate way to do the work. You can then mark the lines using chalk or spray paint. 

This is a good way to determine the length of pipe that you will need for this part. Then you can purchase the pipes.

Make sure they are the same quality and material as the existing pipes, if not better. Try to be as precise during this stage as possible. This can save you from a ton of costly mistakes down the line. Double check that you know exactly where the existing pipes are before you start. 

Mark Your Cut

Your drain lines need to be in their simplest configuration for this to work and there should be as few twists and turns to them as possible when you do this. Determine the center of the new line, starting at the origin point and where it would end. The center of this needs to have an X with spray paint before you draw two lines on either side of it to get your complete mark. 

Cut the Concrete

When you’re ready, it’s time to get going with some of the more physical work. Cutting through concrete takes time, so be patient with during this step.

You can take the diamond blade on the wet concrete saw and place it right on the X, which is the center of the drain line that we used before and cut in about 4.5 inches deep.

Continue cutting along both of the marked lines that we did before. This step will be noisy and will take some time to do correctly, so do not try to hurry it through. You will be cutting through the concrete, so take some breaks if you need. 

Cutting Through Rebar

Many concrete slabs are reinforced with rebar, which you’ll also need to cut through. These are meant to help strengthen the concrete and prevent it from cracking. So keep in mind that because of this it does mean more time and effort for you when dealing and cutting through it all. 

Remove The Concrete

Once you have been able to cut through both of the lines, you can use a sledge hammer and a demolition hammer if it is necessary. This will help to break the concrete strip into chunks. Remove the remaining pieces of concrete and then you may need to dig into the soil and sand to make the drain trench that you need. This is where you will need the mechanical digger or hammer drill.

During this time, you must make sure that you wear the right safety equipment. This include protective eyewear and the right back support. This will keep you safe from any of the injuries that could show up. You should also move the concrete junk before bringing in the new pipes that you would like to use. 

Install the Conduit

Now we’re ready to install the conduit. We will install it right into the drain trench, making sure that the pipe rests on enough pipe support.  

One thing to remember here is that the tubes should extend at least six inches above the top of your concrete. If you can’t help but have a turn or a twist, make sure that a high-quality pipe joint of the right shape is installed in place. The best way to get this all done is to measure and mark ahead of time so you do not have to stop and go get more materials. 

Cover the Mouths of the Pipe

After you make sure that all of the pipes are secured in place, you can cover the openings of the pipe with tape. This will make sure that debris is not able to enter the pipe at all. without covering this part of the pipe, you can end up with a lot of debris getting into the area and blocking the pipe, sometimes even before you get a chance to pour concrete over it. If the debris does get into the area and the pipes, you will have to break the pipes to figure out where the blockage is and then redo some of the work as well. Cover it up well to help prevent this problem. 

Fill the Trench with Soil and Concrete

To finish this process, it is time to cover up the pipelines with a little bit of soil to start, you can use a hand shovel to get started with this one, filling up the trench so that the backfill ends up as even with the floor as you can get it. When you have the drain up higher than the existing floor, then you will need to be able to level up the entire floor. That’s going to take more time and effort in the process. 

Once you have this as even as you can, it is time to bring in the concrete. You will need to pour the concrete over the soil and then let it set. The amount of time will depend on how much concrete you plan to use in the process. Make sure that nothing disturbs it during this time either. 

Can I Move Plumbing from a Concrete Slab?

The steps that we just went through were all about installing plumbing inside of the concrete slab, but are you able to move it around inside the concrete as well. It is something that can be done, but the job will be messy, time consuming, and will use more mechanical precision than we saw with the other steps that you just completed. Many choose to work with a professional to make it a little easier. 

If you need to move around the plumbing inside of some concrete, it can be expensive. It will cost between $2000 and $7000 to do this in a kitchen of 200 square feet. If you do decide to do this process on your own, you will need to do some careful sawing and digging to make sure the pipe is not broken. Once the pipes are gone, you can add in another cut for the new drain line. Install the pipes and level up the floor to finish it off. 

How Deep are the Plumbing Pipes Under a Slab House?

This is going to depend on the specific home and some of the regulations in the area. It is possible for the plumbing pipes to be about 18 inches to 3 feet deep under the slab house. They are meant to be buried below the frost line in general, but there are times when they will be above this line, only if they are insulated to make sure damage does not happen. If you have pipes on the outside of the home, they need to be about four feet under so they do not freeze and burst on you during the winter. 

Installing the Conduit

This is a process that takes some time and a lot of care and attention. Do not just dive right into it and hope everything will work out, or you will need up with a big mess and a lot of wasted money. It is possible to hire a professional plumber to get the work done, but with a little bit of attention and the steps that we have above, you will be able to handle the installation on your own!

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