The difference between a standard or fixed length linear drain and an adjustable linear drain

One of the questions we get asked most frequently is when should I use a standard or fixed size linear drain versus an adjustable linear drain.

There are a few important elements to consider when selecting which drain is best for your project:

The length of the drain

When the drain requested is long, for example, 78”, or for an exact length that is not available in our fixed length series, the best choice is an Adjustable linear drain.

An adjustable linear drain can be built to a custom length for interior use in a shower or for exterior use, such as along a deck, balcony, patio, pool area, exterior shower, exterior kitchen, etc.

They are sold as a Kit, with all the parts included building the complete drain. The possibilities are endless, you can connect as many kits as needed and even create corners using the corner connector kit.

When the size of the area is standard, which is in most cases, you can use a standard linear drain. They are available in many sizes: 24”, 28”, 32”, 36”, 48”, 58”.

Drains don’t need to run the full length of the wall, which allows you to use a standard length in most projects.

For example, if you have a wall that is 38” long, you can install a 36” or even a 32” and it will look and work perfectly. In my opinion, I think it looks better, it’s just a matter of taste.

High Flow Water

GPM means Gallons Per Minute. Also known as “flow rate”, GPM is a measure of how many gallons of water flow out of your shower head each minute.

A standard or fixed length linear drain has a 2” outlet.

If you are designing a shower that has a GPM higher than what a standard 2” pipe will handle, you need to use an Adjustable Linear drain.

Adjustable linear drains are offered in 2” outlet or a 3” outlet for High Flow Water Intake. The majority of residential indoor plumbing uses standard 2” plumbing pipes, and exterior plumbing has 3” plumbing pipes.

Location of the Outlet

If the location of the pipe is centered along the wall where you want to place the drain, then a standard or fixed length linear drain works beautifully.

If the pipe is off-center, using an adjustable linear drain allows you to place the outlet anywhere. Then, the drain will appear to be centered, saving the expense of moving the existing pipe.


Adjustable linear drains are more expensive than Fixed or Standard Size Linear Drains.


Adjustable linear drains require assembly prior to installation; standard linear drains are ready for installation.


There are more great design options in Standard Linear drains than in Adjustable Linear drains.

The decision is yours depending on your design needs.

Whether you are replacing a drain in an existing bathroom or designing a bathroom from top to bottom we are here to provide you with the best quality drain.

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