The Role of Waste and Overflow Systems

What does a bathtub waste and overflow system do? 

The waste and overflow system of your bathtub is a very important part of ensuring it functions properly. The system includes two main components: a stoppable drain (the waste system) and an overflow system, placed higher up along the bathtub wall, that prevents water from overfilling and flowing over the top, potentially damaging the bathroom floor, wall, or bathtub surround. The waste system is what we typically refer to as simply a “drain” in everyday conversation. But in bathtub manufacturing, the used water from a bath or shower is referred to as “bath waste” – therefore, this component is titled the waste system. The waste system is what is used to hold water while filling the tub for bathing as well as drain the water after a bath, using a trip-lever or other type of drain stopper to switch between filling and draining. Depending on the bathtub and the bathroom in which it is installed, the overflow system may be built into the interior of the bathtub or can be connected to an external pipe that will connect into a wall or be hidden in the bathtub surround. 

What do I need to know before getting a waste and overflow system? 

The three most important things to know before selecting waste and overflow systems for bathtubs are size, material, and finish. 

Selecting the correct waste and overflow system size will depend on the measurements of three key areas of your bathtub: the drain shoe, the overflow depth, and the depth of your bathtub. A professional contractor can help you accurately measure, but as a general overview: the drain shoe includes the distance from the center of the drain to the surface on which the overflow will be mounted. Check the bathtub manufacturer specifications that were included with the bathtub, as this information is often included there. The overflow depth is essentially a reverse measurement of the drain shoe, starting with the center of the overflow and continuing to the surface on which the drain will be mounted. Lastly, the depth measurement is exactly that – the depth of your bathtub. This is less critical to determining the size of the waste and overflow system but is helpful to have as supplemental information to the drain shoe and overflow depth measurements. 

The material used to manufacture waste and overflow systems is not necessarily an aesthetic choice, as local codes will dictate what materials are acceptable. However, it will make a difference in cutting the waste and overflow system to size, how long it lasts, and what types of fittings will work with it. This is another area in which relying on the knowledge and experience of a professional contractor is extremely helpful. In general, bathtub manufacturers make waste and overflow systems from four types of materials: 

• **Acrylonitrile, Butadiene, Styrene (ABS) – a hard plastic that can withstand wide-ranging temperatures. 
• **Brass 
• **Polypropylene (PP) – a low-density thermoplastic made from propylene that is highly stress-resistant. 
• **Polyvinyl Chloride (PVC) – a durable, long-lasting thermoplastic. 

Finally, selecting the finish for the fixtures of your waste and overflow system is a matter of personal preference as well as consideration for the current look of the bathroom in which they are being installed. If you choose not to match the color of the bathtub, the finishes, colors, and textures on existing hardware and accessories should factor into the decision of a waste and overflow system finish. There is a wide variety of colors and finishes available from traditional styles to more modern designs, so consider the overall aesthetic of the bathtub as well as the bathroom and do your homework on cleaning and care specifics for different types of finishes so there are no surprises once installed. 

Is an overflow system required for every bathtub?  

Not all residential housing and plumbing codes require overflow systems to be included by bathtub manufacturers. While overflow systems are a great added level of protection from overfilled bathtubs, they are not foolproof. The amount of water an overflow system can take in at once is relatively small - so water that is flowing at a heavy rate and left unattended can quickly overwhelm the overflow system and spill over the top. 

Check with the bathtub manufacturer’s specifications or consult with your professional contractor to be sure an overflow system is included before you purchase a bathtub. 

Are there choices in bathtub waste systems? 

The type of waste system - or drain - you have in your bathtub not only affects the overall aesthetics, but waste systems are built with different types of operating systems. Not all waste systems are right for every bathtub, so to make sure you select the most appropriate one, you’ll need to know the construction material of your bathroom’s pipes, the type of actuator used in the plumbing, the size of the drain location, and the type of stopper used. Working with a professional can help ensure you get the most accurate information and avoid mistakes. 

It may surprise you to know there is a wide variety of drain stoppers available. You can select one that best fits your personal preferences and your household's needs. Below is a list of the most common types of drain stoppers with a brief description of how they work. 

Flip-it drain stoppers are relatively simple to use and install. The base of flip-it stoppers is held in place with o-rings to create a seal. A toggle at the top allows for manual opening and closing. 

Lift-and-turn drain stoppers, as the name implies, are manually lifted and turned in opposite directions to open and close the drain. A threaded screw within the design allows for a bit of flexibility in the ability to control the flow of water. 

Trip-lever drain stoppers work with a plunger that is hidden in the overflow pipe and are activated by a lever. Opening and closing the drain is as simple as flipping the lever up or down. The position of the lever indicates whether the drain is open or closed.  

Pop-up drain stoppers are similar to trip-lever drain stoppers. The pop-up drain stopper is activated by a lever, but also includes a spring that seals the drain when activated. To seal the drain, simply push down on the stopper. Pushing it again will reverse the action and allow the sink to drain. 

Push-and-pull drain stoppers feature a small knob that can be pulled to open the drain and pushed down to close it. Similar to lift-and-turn stoppers, they are fairly simple to use and easily fit most bathtub designs 

Toe-touch drain stoppers, or toe-tap drain stoppers, feature a spring-loaded design that can be pressed down with your toe to engage and release. This is a great choice for bathers will mobility issues or difficulty bending down to manipulate the drain with their hands. 

Choosing the right waste and overflow system may not be the most exciting part of remodeling or designing a bathroom, but it’s a critical one. Managing the flow of water can help prevent damage to your bathroom caused by overflows, reduce the risk of slips and falls, prevent mold and mildew build-up, and make it easier to keep the bathtub and surrounding areas clean. They’re a great finishing touch that can be a subtle complement to your bathroom’s aesthetic and help ensure long-term satisfaction and functionality.