What Size Should a Shower Curb Be? (Building Code)

If you’re renovating your bathroom, you’ll need to make sure that your shower has some sort of curb or rim to ensure that the water is properly contained and finds its way to the drain. So what is the correct height for a shower curb?

According to the United States building code, the standard height for a shower curb is 2 inches above the top of the drain. This means that you must have a 2-inch drop from where the drain is located to where you step in. The US building code does not mean that the curb itself has to be 2 inches high.

In this article, I’ll discuss whether shower curbs are even necessary, whether they should be waterproof, and if it’s better to buy a pre-made shower curb or make one yourself (with instructions on how to do so).

shower curb height

Are shower curbs necessary?

As a shower curb can be a pretty big trip hazard, it can be useful to have a shower that does not have a curb. However, there are a few things to consider first. You must check with a building inspector before installing a shower without a curb to ensure that it is safe to do so.

If you have been given the go-ahead, then the next thing to consider is the floor of your shower as curbless showers need to have a drop in the floor so that water doesn’t spread all over your bathroom floor. The slope in the shower itself must be gradual so that it does not cause a hazard when it is wet.

Purpose of a shower curb

A shower curb is used to keep water inside the shower area and prevent it from spilling out onto the floor. A shower curb is essential for preventing water from flooding out if the plughole gets clogged up or the drain backs up. It is also useful for fastening the hinges to if you have a shower door.

The minimum height of a shower curb is two inches, but it does not have to actually be that height. For example – If your shower floor has a slope in it that slants down at a rate of a quarter-inch per foot and the drain is three feet away from the curb then the shower floor is already 3/4 of an inch lower and therefore your shower curb only needs to be 1.25 inches high.

Do shower curbs need to be waterproof?

If you’re installing a ready-made shower then you don’t need to waterproof it as it will have already been made waterproof when it was manufactured. However, other than that then yes, you do need to make your shower curb waterproof.

If you are building your shower area and tiling it yourself then you will also need to make your own shower curb and ensure that it is waterproof. To do this, you can use something like a PVC sheet as a barrier against the water. You could also use a type of liquid barrier that can be painted on, or you could cover the wood with cement and then paint the liquid barrier on.

What materials are used to make shower curbs?

Shower curbs are generally made from wood that has been pressure-treated as it is a strong material that is also water-resistant. It is also possible to make a shower curb from standard wood, or wood that is covered with cement.

No matter which method is used, there still needs to be some kind of barrier to protect the wood from the water and moisture that could cause it to rot.

Ready-made shower curbs are usually made from rubber or kerdi-board. These types of shower curbs are designed to be waterproof already so they can be tiled over immediately, and the only parts that need to be sealed are the corners and joints after it has been installed.

How to build a shower curb (15 steps)

  1. First of all, you need to get some 2 inch by 4 inch pieces of wood and cut them so that they are a snug fit in your shower entrance. Next, you need to screw them to the floor with screws that will not corrode if exposed to moisture
  2. Take a waterproof sheet or pan liner and cover the shower curb, making sure that it is big enough to go out onto the floor and up the walls by around seven inches in each direction. It is essential when doing this to make sure that you don’t puncture the sheet at all.
  3. Take out the top part of the drain cover and lay the curb liner across it then bolt it back down.
  4. Cut a round hole into the liner where your drain is. The hole should only be big enough to reach the bottom bolts of the drain flange.
  5. Take the bolts out of the drain and apply some silicone underneath the curb liner on the bottom half of the drain. Take care while doing this to ensure you don’t get any in the bolt holes.
  6. Push the liner down firmly onto the silicone and then carefully screw the drain flange back in place.
  7. Push the liner up the walls and into the corners and fasten it in place with some tape.
  8. Fold the curb liner over in the corners opposite the shower curb.
  9. Next, go back to the shower curb where it meets the wall and vertically cut the curb liner, then lay the flap over so that the liner covers the curb fully.
  10. Get a metal lathe and put some tape on it so that you don’t accidentally put any holes in the curb liner, then lay the lathe over the curb so that it covers it.
  11. Cover the shower curb with cement or mortar about one inch deep then put a straightedge on top of it and push it down so that it is seated firmly.
  12. Put a layer of cement around half an inch thick on the outside of the curb, making sure you remove any extra with a trowel.
  13. Leave the cement to set for an hour once the inside of the curb is also done.
  14. After it has set for an hour, use a flat trowel and make sure that the shower curb is the right height for the shower door. Also, make sure that both sides of the curb are straight and parallel.
  15. You can now start tiling the shower – do the sides first and then the shower curb.

Best manufactured shower curbs

Even though you might want to make your own shower curb, the best (and easiest) way to install a shower curb is to buy one that has already been manufactured and then fit it into your own shower.

Buying a manufactured shower curb means that you are not having to spend time making one from scratch and it also means that you know you are going to have a shower curb that already has an excellent barrier against water and moisture.

There are plenty of good shower curbs online, including on Amazon, and the best ones to look for are made from waterproof rubber. The rubber is easy to cut to size and can be manipulated into any shape to fit your shower. It is also useful for showers that have no curbs to prevent the water from escaping. It is strong, sturdy, easy to stick down, and good value.

Joshua Milton

I want to share everything I know about home improvement in order to help you. Whether you're a home enthusiast or an industry professional, I have the information that you need.

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