PEX Stub Out Through The Floor (All You Need To Know)

There is no doubt that PEX pipes are better than their traditional copper counterparts. When installing PEX plumbing in your residential or commercial property, you may have to create stub outs.

These extended PEX tubes act as a connection point for future plumbing fixtures like sinks, showers, and toilets. In most occasions, PEX stub outs are usually extended from walls.

Today, however, we will be looking into the process of connecting PEX stub outs through the floor and everything else you may need to know about this setup.

PEX stub outs

Can You Stub Out PEX Pipes through the Floor?

It is possible to stub out PEX pipes through the floor. The process is quite similar to stubbing out PEX pipes through a wall.

In case your plumbing pipes are coming from the basement or a room below, and there is no way you can access the walls. You can build stub outs through the floor.

To pull off such a project, you will need to make holes or openings in the floor. These will act as entry points for your PEX stub outs. You will also need an anchor to hold the PEX tube.

Please note that local building codes may or may not approve the creation of PEX stub outs through the floor. Therefore, before proceeding with such a project, you should confirm with the local regulations.

How to Stub Out PEX Tubing through the Floor?

As mentioned earlier, stubbing out PEX pipes through the floor isn’t very different from doing it on the walls. However, for clarity purposes, here is a step-by-step guide on how you can go about this procedure.

Step 1: Gather Essential Equipment

You will need some PEX pipes. However, there are a couple of things that come in handy, which include; a drill, a PEX crimping tool, a couple of clamps, a PEX cutter, and most importantly, an anchor to provide support for your stub out through the floor.

Step 2: Figure Out a Suitable Location for Your PEX Stub Out

Once you have gathered essential tools and equipment, it’s time to determine where on your floor you intend to create a PEX stub.

I highly recommend finding a location as close as possible to the plumbing fixture you intend to build later on.

Step 3: Drill a Hole in the Floor

Using a drill of your choice, make holes in the location you have identified in the above step. The drilled hole should be bigger than the PEX pipe in terms of diameter. This makes it easier for you to run the PEX stub through the floor.

Step 4: Install Your PEX Stub Out

Grab a piece of PEX tubing and cut it according to the desired length of your stub. Confirm if the tube can fit through the drilled hole and proceed to the next step. Testing before installation is important in ensuring the pipe fits perfectly.

Step 5: Attach an Anchor Over the Floor

An anchor doesn’t just direct the PEX stub out from the floor. It also offers support. Position the anchor over the hole and screw it into position. Insert your PEX stub out through both the hole and the anchor.

Step 6: Finish Up by Crimping the Ring Clap at the End of the PEX Pipe

Grab your crimping tool and clamp it towards the end of your PEX tube.

By now, your PEX stub out will have been perfectly installed through the floor. And when the time comes, you can attach your plumbing fixture via the stub out. You can also check for leaks once you are done installing plumbing within your property.

Water pipes PEX and mounting tools on the table. Plumbing

Problems Associated with PEX Stub Out through the Floor

Building a PEX stub out through floors may seem simple. However, there are a couple of issues you need to be aware of.

1. PEX Pipes are Vulnerable to Pest Damage

If there are rodents in your basement or below the floor, then these bad boys can gnaw through your plastic pipes, leading to costly disasters.

This problem affects both PEX stub outs from the floor and wall. As you consider installing PEX stub outs, you need to deal with any pest issues below your floor. The pest issue can also be avoided by using good old-fashioned copper pipes.

2. Poor Installation Can Destabilize the PEX Tubing

You need to follow the tips I have shared with you when building PEX stub outs from the floor. If you make a mistake, your pipes can be destabilized, which can be problematic. Always use an anchor when creating stub outs from the floor.

What are Some of the Perks of Installing PEX Stub Outs through the Floor?

Apart from the issues mentioned above, there are plenty of benefits you can enjoy from installing PEX stub outs through the floor.

Unlike traditional plumbing pipes, PEX allows you to make long runs below your floor. This can speed up and ease the installation process.

You should also remember that PEX doesn’t sweat when exposed to high humidity. Therefore, it’s perfect for congested areas such as below floors.

Does the Size of a PEX Stub Out Matter When Running It from the Floor?

Not really. A PEX stub out can be as short or as long as you want. Because when the time to attach it to a fixture comes, you can always cut it off or extend it with another PEX pipe.

However, it is good practice to ensure the PEX stub out is extended long enough, preferably a bit further away, to accommodate the finishing of a floor.

Most PEX stub outs are installed during the early phases of building a property. Therefore, there is a good chance that you may need to add a subfloor or other materials, such as tiles which can easily cover up a short PEX stub out.

Is the Installation of a PEX Stub Out through the Floor a Standard Practice?

Even though the idea of running a PEX stub out from the floor may seem strange, it’s a common practice. It’s not always when plumbing systems run through the walls.

Sometimes, you may be forced to source water from the basement or a crawlspace below your floor. In such scenarios, all you need to do is drill a hole and install a stub out using a PEX pipe.

But because various locations have different regulations, you should consult local building codes. This will help avoid unwanted scenarios with the building inspectors.

Is Professional Help Necessary When Installing PEX Stub Out through the Floor?

Installing PEX stub outs through the floor is relatively easy for the average DIY builder. Therefore, you don’t need to hire an expert contractor to help you with this project. Just follow the guide I have shared with you and make sure that you use the correct tools.

However, if it seems too complicated, it’s better to hire an expert than make a mistake during installation.

The cost of paying for a professional installation job is way lower than how much you will spend remedying errors later on. Also, improper installation can infringe on the local building codes.

Was this article helpful?