Does A Double Sink Vanity Share The Same Drain?


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Regarding double vanity sinks, or any double basin for that matter, one of the most common questions is whether it will need to have individual drains. For example, does each sink need its drainage pipe, or can they both share a single one? In this article, we will discuss this specific concern and broaden your knowledge regarding the subject matter. 

Double sink vanities will require individual drains but won’t necessarily need two p-trap plumbing systems. Of course, you can still install two p-traps if you believe that it will optimize the drainage system of your double vanity, but in most cases, you won’t need to.

Besides the drain, you should be aware of other aspects of using a double vanity, such as p-traps and vents. If you wish to know more about proper double sink vanity installation, read on. 

Bathroom Double Sink Vanity Main Components

The double sink vanity is an excellent, stylish, and convenient option for master’s bedrooms with its bathroom. In addition, the ability to have the vanity accommodate users simultaneously is a beautiful and somewhat luxurious touch.

Now, what about the plumbing system of a double vanity sink? Does having two make this part of the fixture more complicated than the standard single sink units? 

Parts of the Bathroom Vanity

Bathroom Vanities classic style

The bathroom vanity features a couple more components than a typical sink. Besides the countertop and sink, vanities also incorporate a cabinet base, drawers, and shelves. The countertop is typically made from high-quality, durable materials such as natural stones. As for the sink, you have the option for a single or double model. The faucet and handle will either be shared or one for each basin. 

Bathroom Vanity Sink Plumbing System

The sink is a pretty straightforward fixture. It is made from waterproof material, typically ceramic, porcelain, or stainless steel. At the middle of the basin is drainage that connects to pipes. Underneath the sink lies the P-trap tube, defined by its ‘P’ shape design. The P-shaped design traps debris and prevents it from clogging the plumbing system. 

Additionally, there are pop-up stopper sinks that you can buy online if your vanity sink does not come with one by default. This sink drain accessory enhances convenience and can help prevent debris from falling into the drainage pipe.

Switching from a Single Sink to a Double Vanity Sink

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If you have a single sink vanity at home, can you upgrade it to a double sink without much fuss? The answer is yes, but there are several factors that you need to consider first. The most important one is if the bathroom space can accommodate a double sink vanity

To help figure out if your vanity can accommodate having two sinks, note that double sinks usually require a vanity six feet in length. In some cases, upgrading to a two-sink vanity might require you to reconfigure that bathroom to slightly open up some extra space.  

Drainage Vents

Vents are a mandatory feature in a drainage system as they can avoid airlocks within the plumbing system which can cause blockage and force water back up the sink. Generally, most bathroom drains utilize a central vent, so this is usually a non-issue. However, we do advise that you consult with your contractor or an expert to know for sure. 

Final Thoughts

Double sink vanities showcase a more luxurious charm, and setting one up in your bathroom is a viable option so long as you have the budget. However, to help avoid any future issues, we highly recommend hiring a licensed professional to do the job. This will guarantee that your vanity sink will be up to code and won’t be installed haphazardly, saving you from future headaches.