Does Shower Pan Need a Pre-Slope?(Solved)

Does Shower Pan Need a Pre-Slope?

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Does Shower Pan Need a Pre-Slope?

Yes, It’s best to pre-slope a shower pan before installing it. This ensures that water from the shower goes into your drainage system, preventing damage to your walls. It also makes cleaning the shower easy, as the water doesn’t pool in the bottom.

It’s easy to find a free-standing pre-sloped shower pan. Look for one with a 1″-deep drain hole in the back and a 2″-high lip at the front. For walls less than two feet thick, seal off the bottom portion of your shower pan with caulk and use regular tile as the front.

If your walls are more than two feet thick, it’s better to pre-slope the shower pan before installing it. The sheet of plywood on top of the regular tile forms a gently sloping base 1-1/2″ high at the back and 2″ at the front.

The drain hole in the back extends down through a 2×6 (or 4×4) subfloor, and you can install a downspout on the floor.

Once the shower pan is in place, caulk around the drain hole, and you are ready to install your tile.

Pre-sloping your pan is also better than plumbing a drain-back shower into an existing enclosure where you built the walls without proper slope angles.

What Do You Use to Pre-Slope A Shower?

A pre-Slope stripA pre-slope strip is a piece of fiberglass membrane or other smooth material that is attached to the sloped wall of a shower. The slope is usually about 1″ for every 10′ in length.
CaulkingCaulk is the best way to seal the seams between pre-slope strips and the top edge of walls where they contact tile or other masonry surfaces.
A TrowelA trowel spreads a smooth layer of mortar and parge onto the wall. This first layer of mortar and parge seals the wall surface, making it easier to apply subsequent layers of tile setting material.
SpacersSpacers are used to keep tile spacing even.
Mastic or Thin-setThis is the material you’ll use to hold down the tile after you’ve positioned it evenly on the wall surface, using spacers as your guide.
Tile Setting MaterialTile setting material is a two-to-three-component mixture of dry mortar and water. It will be applied to the walls and cured with mastic or thin-set.

Do I Need a Pre-Pitch and Quick Pitch?

A Pre-pitch and quick pitch in shower pans are a retype of sub-base that you can install on the shower floor before you pour the rest of the cement. You can use this area for drainage purposes and avoid water pooling problems.

You must have a quick pitch and pre-pitch in a shower pan because the water will get your pitch. The water uses pitch so that it can have a nice slippery feel.

Pitch is not just for playgrounds anymore; it also has many uses in our home and works life. With pre-pitch, you could greatly reduce the likelihood of slipping while showering or taking a bath.

Pre-pitch also makes it easier to clean up after an accident, as you might experience slipping on soap scum during bathing.

The quick pitch is ideal in medium-trafficked areas such as a residential bathroom or basement. Quick pitch also works great in high-traffic areas like a locker room or an athletic field.

Does Shower Pan Need a Pre-Slope?

The quick pitch provides a non-slip surface that is easy to clean and maintain compared to the pre-pitch.

Both pitchers are waterproof, but pre-pitch is more applicable than a quick pitch; for example, you can apply pre-pitch on uneven surfaces. The pre-pitch also will not produce a painful peel-back when peeling it off a surface.

However, the quick pitch is better for high-traffic areas because the quick pitch is more durable than the pre-pitch. Quick pitch has a stronger bond and resistance to tearing and this makes it a great choice for athletic surfaces.

The quick pitch is also more forgiving when you apply it over uneven surfaces, making it the best option for floors and other surfaces with uneven terrain.

How Much Slope Does a Shower Pan Need?

You will need a slope of 1″ per foot. The most important measurement to make is the height of the shower pan. You will need a height of 24 inches for the front of the shower pan.

The next important measurement is measuring the stair thickness at each side of the opening in your walls where you want to place your shower pan. What you are looking for here is “stair thickness + 1”.

You will be unable to use any of the existing walls as a so-called wall “in-plane” support for your shower. This is the measurement from the top of the floor to the top of your side walls.

Your shower pan will fit snugly into the opening between the walls and the top of your steps; The wall thickness is the thickness of the wall from the top of the floor to where you want your shower to go.

In most cases, it is pretty much just what is lying against your walls at this point. You will need a 2-inch stair thickness + 1″ for each side of the opening.

If you don’t make a good measurement at these two points, you will have to cut some additional sections out of your walls that will support your shower pan, and they will probably be very thin sections too.

How Thick Should the Pre-Slope Be?

In most cases, The pre-slope in a shower must be at least 1 inch thick. This is to accommodate the difference in height between the bottom of a shower enclosure and the floor outside.

Should this height difference exceed 8 inches, you’ll need to add 3/4 inch of slope for each extra 8 inches.

For example, if you have an allowance of 12 inches for your incline, you’d need a 1-1/2 inch pitch slope. If your slope extends beyond the point you’re willing to keep, you can probably go up to 1-inch.

If your slope is too low, you’ll have problems with water cutting through the walls of your shower and draining down onto the floor. It’s a good idea to check the roof pitch of your house before constructing a shower enclosure to know what need.

A pitch less than 1-inch is too steep for a pre-slope. This can result in water draining onto the floor, even when you turn off the shower, measure the pitch of your roof using a slope meter.

If your roof is below 1/12 on average, you’ll need to add more rise (vertical distance) before creating a pre-slope to level with the outside ground. The equation for calculating the amount of rising required is as follows:

Rise Required = (Height from Ground to Outside of Shower Enclosure) X (1/.002)

Example : A 1-inch pitch is required, but the roof height from the ground to the outside of the enclosure is only 7″, making it a 1/12 slope. The formula for creating a pre-slope would be as follows: 7 x (1/.002) = 7.

What Fall Is Required for Shower Waste?

At least 10mm fall for every 4m pipe diameter is needed for a shower waste to operate. If you are building a new home with wider pipes, then at least 20mm fall per 4m should be laid.

When installing the waste for new properties, the minimum fall should boast first installation and other system parts fitted in afterward.

The fall of water from a shower head is necessary for particles to break free from it before exiting down the drain.

Does Shower Pan Need a Pre-Slope?

If you don’t install proper shower waste, you will receive a back pressure of water that will cause blockages in the drain hose and pressure of excess water entering the drain.

In cases where larger welded joints (often referred to as pop joints) are installed, such as:

Water left in any shower room or bathroom facility can harm your home. This can lead to mildew growth, which can cause significant damage over time.

Operating shower waste104
A new home204

How Many Falls Should a Shower Have?

The recommended number of falls for a shower is about ten per hour, but this number will vary depending on the person’s weight and other factors. You can base this on health, age, and size of the bathroom.

Besides the overall size of the bathroom, this will affect how many falls you should have.

For example, if there is a lot of space in the bathroom, you can fall more than someone trying to shower while cramping in a small area. Therefore, you need to consider this when looking at different options for your bathroom.

The length of the shower is also something you need to consider. If you take a very long shower, you will likely have more falls.

How Do You Install a Perfect Slope Shower Pan?

To install a perfect slope shower pan, use the following steps:

  • Measure the opening, and plan out your shower. Then take the measurements to your local home improvement store.
  • Make sure you purchase a slope shower pan that is a little bigger than what you measured for, so you can cut it down to size after installation.
  • Purchase a slope shower pan with an integrated flange so it will be easier to install.
  • Use a cordless drill and an auger bit to drill holes into the shower pan’s floor, walls, and ceiling.
  • Measure the width of the shower pan, then remove the existing wall tile.
  • Cut a piece of matboard from your local home improvement store shaped like your shower’s outline.
  • Tape this to the wall where you plan on installing your new slope shower pan. It will help you ensure that the slope of your new shower pan is right.
  • Purchase an adhesive to go over the existing tile. Then apply your adhesive to the back of the matboard, and press it against the wall.

Once that is done, place your shower pan onto the wall on top of the tape and tile.

Then use your drill and auger bit to install bolts through pilot holes from one side of your shower pan into each bolt hole from the other between two tiles. The two sides should be on opposite sides of your new shower pan.

Is The Kerdi Shower Pan Sloped?

Yes, It has a slope of 18.5 degrees or 256 inches per foot. The maximum slope is 30 degrees or 452 inches per foot. The minimum is zero, and the faucet head must protrude over the edge of the pan for proper showering use.

The water pressure exceeds 4 pounds per square inch in a shower. If the water pressure is over four Psi, then you should slope the top of the pan to 20 degrees. The pan should be flat if the water pressure is under four Psi.

Also, the kerdi shower pan should slope 6 degrees (or 1/8″ per foot) towards the shower drain. If it does not, you will have water pressure and performance problems. You may also have issues with leaks in the slab next to it.

Does Shower Pan Need a Pre-Slope?

I use a simple paper template to verify this. A shower drain that allows the kerdi shower pan to slope in the correct direction will keep water from reaching the slab next to it.

A Kerdi shower pan not sloped correctly will allow water to flow through the slab and into the shower drain.

How Do You Install A Shower Pan On A Wood Subfloor?

  1. Make sure your subfloor is level. If your floor isn’t level, it’s harder to adhere the shower base panels together, and the mortar will crack.
  2. Use a laser level or a piece of 2-by-4 wood to check for even levels across the surface of your concrete slab foundation.
  1. Measure the width and length of your shower area. This will make it easier to cut pieces of plywood to the right size.
  1. Cut your base panels to fit the shower area, then glue them together with construction adhesive. Once you secure all your base panels, put a light coat of mortar on the joints. Let it dry completely before installing.
  1. Adhere your base to the concrete slab foundation with masonry rings or an adhesive tube (follow the manufacturer’s instructions). Make sure the panels are level for even adhesion.
  1. Install the shower pan. You’ll have to buy special shower pans that match the wood subfloor. Place a sheet of plywood over the top of your shower base, then cut holes for your shower drain and your showerhead.

Set the pan over your base and secure it by fastening it to the studs with masonry screws or ring anchors (follow the manufacturer’s instructions).

  1. Waterproof your base. You can use an exterior wood sealer or roofing tar on the joints (after it dries, use an exterior paint or stain to waterproof it).
  1. Clean up any debris and wash down all surfaces.

How Thick Should the Dry Pack Be for The Shower Pan?

The dry pack should also be at least 2” in height at points where it would meet with anything underneath, like a floor. This is called the “flashing” height, which helps prevent a water leak.

The threshold for flashings is at least 6 inches in height. With this in mind, your shower pan needs to be about 4″ high and have a thickness of between 2″ and 4″.

Regular tiles are not meant to cover the bottom of an outdoor pool because they will not remain watertight. The dry pack base should be thicker material such as cement, soil, or tile backer board.

The floor tiles are too thin to cooperate with the concrete and set properly.

The key is to prevent water seepage through your shower floor and have it drain into the pool underneath. You’ll need to make sure your ground is perfectly even for this to work properly.



Pre-pitch and quick-pitch are the most used to install the Kerdi shower pan. They are prefabricated and ready to install out of the box.

You need a good amount of adhesive along with the shower base panels. Install them on a flat concrete floor and let them dry for 48 hours before you can use your shower pans.


Hi! I I faced many questions from customers about different products, and there was hardly any help on the internet. After learning all the things about these products as a manager the hard way, I decided to start a blog and help other people.

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