how many bends can you have in a drain pipe

How Many 90s Can You Have In A Drain Pipe?

Several house-owners undervalue the role drain pipes play in their plumbing network. It’s an essential part of the design of a home’s plumbing system that needs attention and thus explains why this article seeks to answer: how many bends can you have in a drainpipe?

It is highly advisable to avoid using any 90s in your sewer line. Its recommend limiting the bend to 45 degrees, then installing a straight pipe before attaching an extra 45-degree twist. 

Your drain pipe can have either 45 or 90 degree bends. However, professional plumbers recommend the installation of 45 degrees as opposed to 90-degree ones, citing susceptibility to unnecessary damages and blockages. 

The principal worry with a drain bend is clogging, and that’s the last thing you want from this setup. This article sinks deeper into the subject. 

How Many 90s Can You Have in a Sewer Line

Once the toilet drain hits a vertical wall, it falls downwards between the wall studs. Even though there is a downward drop, do not join the pipes using typical 90-degree piping elbows, sometimes known as “hard 90s”.

Clogs are more likely with these elbow fits because of their sharp edges. Essentially you should have no 90s in your sewer line.

Can You Use a 90 Degree Elbow in a Drain Pipe

Drain lines can have elbows. Some apartment owners see it fit to incorporate 45-degree elbows into their drain lines to create the horizontal p-trap link. 

Nevertheless, this violates regulations and can cause problems. 

You cannot use them to connect a vertical drain to a horizontal pipe or two horizontal conduits. Depending on the layout, a long or short sweep elbow, a wye, or a tee could come in handy. 

Furthermore, you cannot reverse the direction of a drain line using a 90-degree vent elbow because of frequent clogging. 

Can You Put A 90 in a Toilet Drain

A severe 90-degree bend on a horizontal outlet pipe embedded in a slab or otherwise covered is a terrible plumbing technique because sewer cleaning equipment has difficulties passing through the 90-degree turns. 

Avoid installing a 90-degree adapter underground unless used at the bottom of a vertical piping stack. 

If you need to make a 90-degree turn, employ two 45-degree angle adapters partitioned by a 12 or 18-inch length of straight pipe. 

See also Standard Toilet Drain Pipe Size

Can You Have a Bend In A Waste Pipe

You can have a bend in a waste pipe. Below are some recommendations when making bends in a waster pipe.

1) Avoid Making 90-degree Bends

90-degree twists in a drainage system might result in a limited plumbing network that can cause complications in the future. You must understand the mechanics of these sets of turns for a toilet drain. 

The waste will move unnaturally, thanks to the more acute bends. When this occurs, the waste is more likely to become trapped or blocked inside the drain, and you will have many problems. 

Consequently, professional plumbers advise against integrating 90-degree curves in toilet drains. They don’t work unless you employ two 45 degree bends. 

It is unsafe to have a toilet drain curve 90 degrees because it will result in a situation in which an increased flow rate will block the drain line in minutes. 

2) Integrate A Straight Pipe Between The 45-degree Bends

Several 45-degree twists in the pipe will allow waste to pass through without clogging the toilet drain. 

To get this correctly, install a straight conduit between the two curves. It guarantees that the water keeps flowing through and has the time to accumulate pressure before entering the next curve. 

3) Spread Out The Bends

Bends in the drains will demand a great deal of forethought. Several house-owners, particularly those whose toilet drains feature several curves, make the mistake of sitting back and hoping things will work out. 

Take time to figure out where the drain bends should be and spread them out as far as workable. Failure to address this will cause complications in the toilet waste draining system. 

Always seek to extend out the drains as much as possible. 

4) Use Only When Necessary

You’ll want to double-check that bending the toilet drain is not a mere show. Use it as a last option if the plumbing can’t function without a bend. 

Bending toilet drains is prevalent in buildings where the toilet drain requires a vertical drop. You must only implement this sort of functionality when it is necessary. 

Keep this in mind when determining the requirements of a toilet to discharge waste correctly. 

See also Vortens Toilet Reviews

Can You Put A Bend In Underground Drainage?

You can have a bend in an underground drainage or waste pipe. They are the direction adjustments on a plumbing system across most materials from 11 1/4 to 90 degrees. 

Long and short radius curves are also available in single, double, or double-ended sockets. 

See also How Many Toilets on a 3 Inch Drain

FAQs on How Many Bends Can You Have In A Drain Pipe?

1. How Many Bends Can You Have In A Soil Pipe?

The bends near the bottom of the stacks should have a long radius. Alternatively, you can employ two 45 degree bends. 

The same principle applies to offsets. 

2. Why Do Toilets Have So Many Bends?

The S-trap (a large curved conduit at the foot of the toilet) traps some water that seals the drainage line beneath, preventing bacteria and unpleasant odors from entering your bathroom. 

3. How Much Do 90-degree Elbows Affect Water Flow?

A 90-degree elbow with a hard turn equates to 17 feet of straight tube. Two solid turns on 90-degree elbows can cause a 52 feet pressure drop in the straight pipe. 

4. Do Bends Affect Flow Rate?

If the bend geometry is severe enough, the adverse pressure gradient at the external wall in the curve and around the inner wall shortly after the bend may cause flow separation at these spots. It could result in significant pressure drops. 

5. Is A 45-degree Elbow Better Than A 90-degree Elbow?

45-degree elbows produce less head loss than their 90-degree counterparts. Other possibilities include increasing the pipe size that decreases friction or using Spaflex PVC curved in a smooth bend.

6. Do 90-degree Bends Affect Water Pressure?

Unless all 90 bends feature a smaller inner diameter, they should have little influence on pressure.

See also Should A Toilet Drain be 3 or 4 Inch?


According to the post, your drain pipes can feature 45 and 90-degree bends. Plumbers recommend capping the bend at 45 degrees to minimize damage or clogging. 

If you make a 90-degree curve in the drain, you’ll probably create a clog.

If you decide to add numerous bends, set them at 45 degrees to ensure that the waste securely and uninterruptedly passes through the drain. That’s why it’s wise to backtrack and think about how you’ll operate the drain. 

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