SDR 35 vs Schedule 40 – Which PVC Pipe Comes Out on Top?

When it comes to choosing the right type of PVC pipe for your project, the two most common options are SDR 35 and Schedule 40 PVC pipes. Both pipes are used extensively in plumbing, irrigation, and drainage applications, but they have different characteristics that make them more suitable for certain projects than others. In this blog post, we’ll explore the pros and cons of each type of pipe, and help you make an informed decision about which one to use for your next project.

Contents

SDR 35 PVC Pipes

SDR 35 PVC pipes are a type of pipe that are designed for use in low-pressure sewer applications. They are typically made from polyvinyl chloride (PVC) resin, and are known for their smooth inner walls, which reduce the amount of friction and resistance within the pipe. This can help to increase the flow rate of liquids and solids through the pipe, making them ideal for drainage applications.

Pros

Smooth inner walls allow for high flow rates

Flexible and easy to install
Resistant to corrosion and chemicals

Cons

Lower pressure rating than Schedule 40 pipes

More prone to damage from roots and other underground obstructions

Schedule 40 PVC Pipes

Schedule 40 PVC pipes, on the other hand, are designed for use in high-pressure applications. They are thicker and stronger than SDR 35 pipes, which allow them to handle higher pressure and flow rates without bursting or leaking. They are commonly used in plumbing, irrigation, and other applications where high-pressure water or air flow is required.

Pros

High pressure and flow capacity

Durable and resistant to damage from impact and pressure
Widely available and easy to find

Cons

Not as flexible as SDR 35 pipes, which can make installation more difficult

Higher cost than SDR 35 pipes

Differences between SDR 35 and Schedule 40 PVC Pipes

Size and Thickness Differences

One of the main differences between SDR 35 and Schedule 40 PVC pipes is their size and thickness. SDR 35 pipes are typically available in smaller diameters than Schedule 40 pipes, and are also thinner and more flexible. Schedule 40 pipes are larger and thicker, which allows them to handle higher pressure and flow rates without bursting.

Pressure Rating Differences

Another key difference between the two pipes is their pressure rating. SDR 35 pipes are designed for low-pressure applications, and typically have a pressure rating of 35 psi. Schedule 40 pipes, on the other hand, are designed for high-pressure applications and have a pressure rating of 140 psi or higher.

Cost Differences

There is also a significant cost difference between SDR 35 and Schedule 40 PVC pipes. SDR 35 pipes are generally less expensive than Schedule 40 pipes, which makes them a popular choice for budget-conscious projects. However, the higher cost of Schedule 40 pipes is often justified by their greater strength and durability.

Environmental Considerations

Both SDR 35 and Schedule 40 PVC pipes are environmentally friendly and can be recycled after use. However, SDR 35 pipes are often preferred for their lower environmental impact, as they require less energy and resources to produce and transport.

Comparison Table: SDR 35 vs Schedule 40 PVC Pipes

Factor	SDR 35 PVC Pipes	Schedule 40 PVC Pipes
Pressure Rating	35 psi	140 psi or higher
Diameter	Smaller	Larger
Thickness	Thinner	Thicker
Flow Capacity	Lower	Higher
Flexibility	Higher	Lower
Cost	Less expensive	More expensive
Environmental Impact	Lower	Higher

Summary

In summary, SDR 35 and Schedule 40 PVC pipes are two commonly used types of pipes that have distinct differences. SDR 35 pipes are typically used in low-pressure applications and are known for their smooth inner walls, flexibility, and resistance to corrosion and chemicals. On the other hand, Schedule 40 pipes are designed for high-pressure applications and are thicker, stronger, and more durable than SDR 35 pipes.

When deciding between the two types of pipes, it is important to consider factors such as pressure rating, diameter, thickness, flow capacity, flexibility, cost, and environmental impact. Ultimately, the right choice will depend on the specific needs of your project, including the type of application, the amount of pressure and flow required, and the budget available. By understanding the pros and cons of each type of pipe, you can make an informed decision and ensure that your project is successful.